Image reading system, image reading device, and image reading method

Abstract

To provide an image reading system, an image reading control device, an image reading device, an image reading method, and a program capable of appropriately selecting an image to be blank and setting a blank removal level with a simple operation.SOLUTION: An image reading system having a blank sheet removal function includes: a preview display processing part that displays a preview of at least a part of an image of a read document on a display part in a selectable state; a display switching part that switches a display mode of the image to a selected state in which a blank sheet removal candidate or a non-removal candidate is selected when the image is selected by an operation of an input part; a data generation part; and a blank sheet removal level setting part. When the selection state is confirmed by the operation of the input part, the data generation part generates read data based on the remaining image data obtained by removing the image data of the blank sheet removal target including the confirmed blank sheet removal candidate from the image data of an original document. The blank sheet removal level setting part sets a blank sheet removal level at which the confirmed selected image can be used as the blank sheet removal candidate.SELECTED DRAWING: Figure 12

Description

[Technical Field]

[0001] The present invention relates to an image reading system including an image reading device that reads an image from a document, an image reading control device, an image reading device, an image reading method, and a program. [Background technology]

[0002] For example, Patent Document 1 discloses an image reading device that reads an image from a document. This image reading device has a blank page removal function that removes blank pages from images obtained by reading multiple documents. The image reading device has an ADF that feeds the document to a reading position, and a blank page determination unit that determines whether the document is a blank document using image information associated with each line sensor of a color line sensor from the read image information. The blank page determination unit determines whether the document is a blank document based on the image information associated with each line sensor of the color line sensor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-118169 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the image reading device described in Patent Document 1 has the problem that images of documents that the user does not want to remove as blank pages are removed as blank pages, or images of documents that the user wants to remove as blank pages are not removed as blank pages. [Means for solving the problem]

[0005] An image reading device that solves the above problem is an image reading system that includes an image reading device that reads a document and an image reading control device that controls the image reading device, and that has a blank page removal function that removes, as blank pages, images of the document read by the image reading device that are blank page removal candidates and that meet a blank page removal level. The image reading system is equipped with: a preview display processing unit that displays a selectable preview of at least some of the images of the read document on the display unit; a display switching unit that, when the image is selected by operating the input unit, switches the display state of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; a data generation unit that, when the selection state is confirmed by operating the input unit, generates read data based on the remaining image data from the image data of the document after removing image data that is subject to blank page removal, including the confirmed blank page removal candidate; and a blank page removal level setting unit that sets a blank page removal level that allows the confirmed selected image to be a blank page removal candidate.

[0006] The image reading control device that solves the above problem is an image reading control device that controls an image reading device that reads a document, and has a blank page removal function that removes, as blank pages, images from the images of the document read by the image reading device that meet a blank page removal level. The image reading control device includes: a preview display processing unit that displays a selectable preview of at least some of the images of the document read by the image reading device on a display unit; a display switching unit that, when the image is selected by operating the input unit, switches the display state of the image to a selection state in which a blank page removal candidate or a non-removal candidate is selected; a data generation unit that, when the selection state is confirmed by operating the input unit, generates read data based on the remaining image data from the image data of the document after removing image data that is subject to blank page removal, including the confirmed blank page removal candidate; and a blank page removal level setting unit that sets a blank page removal level that allows the confirmed selected image to be a blank page removal candidate.

[0007] An image reading device that solves the above problem is an image reading device with a blank page removal function that removes, as blank pages, images that meet a blank page removal level from among images read from a document, and is equipped with: a preview display processing unit that displays a preview of at least some of the images of the read document on a display unit in a selectable state; a display switching unit that, when the image is selected by operating the input unit, switches the display state of the image to a selection state in which a blank page removal candidate or a non-removal candidate is selected; a data generation unit that, when the selection state is confirmed by operating the input unit, generates read data based on the remaining image data from the image data of the document after removing image data that is subject to blank page removal, including the confirmed blank page removal candidate; and a blank page removal level setting unit that sets a blank page removal level that allows the confirmed selected image to be a blank page removal candidate.

[0008] An image reading control method that solves the above problem is an image reading method that performs blank page removal processing to remove, as blank pages, images that satisfy a blank page removal level from among images read from a document by an image reading device, and includes previewing at least some of the images of the read document on a display unit in a selectable state, and when the image is selected by operating the input unit, switching the display state of the image to a selection state in which a blank page removal candidate or a non-removal candidate is selected, and when the selection state is confirmed by operating the input unit, generating read data based on the remaining image data from the image data of the document after removing image data that is subject to blank page removal, including the confirmed blank page removal candidate, and setting a blank page removal level that allows the confirmed selected image to be a blank page removal candidate.

[0009] The program for solving the above problem is a program executed by a computer that realizes a blank page removal function that removes blank pages that meet a blank page removal level from images of a document read by an image reading device, and causes the computer to execute the following steps: a preview display processing step of displaying a selectable preview of at least some of the images of the document read by the image reading device on a display unit; a display switching step of, when the image is selected by operating the input unit, switching the display state of the image to a selection state in which a blank page removal candidate or a non-removal candidate is selected; a data generation step of, when the selection state is confirmed by operating the input unit, generating read data based on the remaining image data from the image data of the document after removing image data that is subject to blank page removal, including the confirmed blank page removal candidate; and a blank page removal level setting step of setting a blank page removal level that allows the confirmed selected image to be a blank page removal candidate. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view showing an image reading device according to a first embodiment. [Figure 2] FIG. 2 is a schematic cross-sectional side view showing the image reading device. [Figure 3] FIG. 2 is a block diagram showing the electrical configuration of the image reading apparatus. [Figure 4] FIG. 10 is a diagram showing a first setting screen. [Figure 5] FIG. 4 is a diagram showing a first management table. [Figure 6] FIG. 10 is a diagram showing a second setting screen. [Figure 7] FIG. 10 is a diagram showing a second management table. [Figure 8] FIG. 10 is a diagram showing a blank sheet determination table. [Figure 9] FIG. 2 is a block diagram showing a detailed configuration of an image processing unit. [Figure 10] 10 is a graph showing a histogram used to determine whether a document is a blank document. [Figure 11] Flowchart showing screen transitions. [Figure 12] FIG. 10 is a diagram showing a blank preview screen. [Figure 13]10 is a flowchart showing a blank page removal processing routine. [Figure 14] FIG. 10 is a diagram showing a blank preview screen. [Figure 15] FIG. 10 is a diagram showing a blank preview screen. [Figure 16] FIG. 10 is a diagram showing a document preview screen in the second embodiment. [Figure 17] FIG. [Figure 18] FIG. [Figure 19] 10 is a flowchart showing a blank page removal processing routine. [Figure 20] 11 is a flowchart showing a blank preview screen display processing routine in the third embodiment. [Figure 21] FIG. 10 is a diagram showing a blank preview screen. DETAILED DESCRIPTION OF THE INVENTION

[0011] (First embodiment) A first embodiment of an image reading device will be described below with reference to the drawings. 1, the image reading device 11 of this embodiment includes a main body 12 having a substantially trapezoidal shape in a side view, and a document support 13 on which a document D to be read is placed (set). A stacker 15 is housed in the main body 12 below an outlet 12B in a state in which it can slide forward and backward.

[0012] The document support 13 has a flat loading surface 13A that extends obliquely upward and rearward from the main body 12, on which multiple documents D can be placed. The document support 13 is provided with a pair of edge guides 13B that are slidable in a width direction X that intersects (particularly perpendicular to) a transport direction Y in which the documents D are transported. The documents D loaded on the loading surface 13A are positioned in the width direction X relative to the feed opening 12A by being sandwiched between the pair of edge guides 13B. The document support 13 is provided with a document positioning mechanism 17 that includes a slide mechanism that slides the pair of edge guides 13B in the width direction X in conjunction with each other. In addition, a sliding auxiliary support portion 13C is provided on the loading surface 13A of the document support 13 so as to be able to move in and out. The documents D loaded on the loading surface 13A are positioned in the transport direction Y relative to the feed opening 12A by coming into contact with the sliding auxiliary support portion 13C. The width direction X is the main scanning direction when the image reading device 11 reads the image of the document D, and the transport direction Y is the sub-scanning direction.

[0013] The originals D placed on the original support 13 are fed one by one into the main body 12 through a feed port 12A that opens at the top of the main body 12. The fed originals D are transported along a predetermined transport path 29 (see FIG. 2) within the main body 12, and after the image is read in a reading area SA during the transport, the originals D are discharged from a discharge port 12B that opens at the front bottom of the main body 12.

[0014] A power button 20 is provided on the front surface 12C of the main body 12. A display unit 22, such as a liquid crystal panel, that displays a predetermined image in a display area 23 is provided on the front surface 12C of the main body 12. The display unit 22 is configured to display information related to the image reading device 11. The display unit 22 is provided with an input unit 21, such as a touch panel, that can detect a user's tactile operation. The input unit 21 is configured to be able to input necessary information in response to a user's tactile operation when giving instructions to the image reading device 11.

[0015] 2, the main body 12 includes a main body portion 18 and a cover portion 19 rotatably connected to the front end portion of the main body portion 18. The main body 12 has a conveying path 29 (conveying passage) extending between the main body portion 18 and the cover portion 19 from the inlet 12A to the outlet 12B.

[0016] The main body 12 is provided with a transport mechanism 30 that transports the originals D. The transport mechanism 30 has a feed section 30A that guides and feeds the originals D stacked (set) on the original support 13 into the main body 12 one by one, a transport section 31 that transports the fed originals D along a transport path 29 so as to pass through a reading area SA, and a discharge section 32 that discharges the originals D after their images have been read during transport by the transport section 31. The transport mechanism 30 has an automatic document feed function that transports multiple originals D stacked on the original support 13 one by one in order along the transport path 29 so as to pass through the reading area SA.

[0017] The feeding unit 30A is provided with one feeding roller 33 (pickup roller) facing the feeding guide 30B at the upstream end position of the transport path 29 inside the main body 12. The feeding unit 30A feeds the multiple documents D stacked on the document support 13 one by one from the feeding opening 12A along the feeding guide 30B.

[0018] The transport unit 31 includes a feed roller pair 34 disposed downstream of the feed roller 33 in the transport direction Y, and a transport roller pair 35 disposed upstream of the reading area SA in the transport direction Y. The feed roller pair 34 is composed of a drive roller 34A and a separation roller 34B (retard roller). The transport roller pair 35 is composed of a drive roller 35A and a driven roller 35B.

[0019] The discharge section 32 includes a pair of discharge rollers 36 arranged downstream of the reading area SA in the transport direction Y. The pair of discharge rollers 36 is composed of a drive roller 36A and a driven roller 36B. The pair of discharge rollers 36, together with the pair of transport rollers 35, also transport the document D during reading.

[0020] In this manner, the feed roller 33, the feed roller pair 34, the transport roller pair 35, and the discharge roller pair 36 are arranged in this order from the upstream side in the transport direction Y, and each pair is arranged at an interval in the width direction X.

[0021] The multiple rollers 33, 34A of the feed system are driven to rotate by the power of a feed motor 37, which is their power source. The multiple documents D stacked on the document support 13 are fed one by one, starting from the lowest one, from the feed opening 12A into the main body 12 by the feed rollers 33. In this way, the feed section 30A (rollers 33, 34A, etc.) is driven by the feed motor 37 as its power source.

[0022] Furthermore, separation roller 34B of the feed system and drive rollers 35A and 36A of the transport system are driven to rotate by the power of transport motor 38, which is their power source. Document D fed into main body 12 by feed roller 33 is transported to reading area SA and then discharged from discharge opening 12B. In this way, transport unit 31 (pair of transport rollers 34, etc.) and discharge unit 32 (pair of discharge rollers 36, etc.) are driven by transport motor 38, which is their common power source.

[0023] Furthermore, the drive rollers 35A and 36A are driven to rotate so as to transport the document D at the same transport speed (reading speed) when reading the document D. The driven rollers 35B and 36B rotate together with the rotation of the drive rollers 35A and 36A that form pairs with them.

[0024] Also provided within the main body 12 is an encoder 44 (e.g., a rotary encoder) that can detect the rotation of one of the drive rollers in the transport system among the multiple roller pairs 34 to 36. The encoder 44 outputs a detection signal containing a number of pulses proportional to the amount of rotation of the drive roller to the control unit 50 (controller). Therefore, based on the detection signal from the encoder 44, the control unit 50 can grasp the position (transport position) and transport speed of the document D being transported in the control unit 50.

[0025] In addition, a document sensor 45 is disposed between the pair of feed rollers 33 to detect the presence or absence of a document D set on the document support 13. The document sensor 45 is, for example, a contact sensor having a lever, and when a document D is set on the document support 13, the set document D presses the lever, turning it ON.

[0026] Furthermore, a document presence sensor 46 capable of detecting the presence or absence of a document D is disposed at a position slightly downstream of the nip point of the pair of transport rollers 35 in the transport direction Y. The document presence sensor 46 is, for example, a contact sensor having a lever (contact). The document presence sensor 46 detects the document D when the leading edge of the document D presses the lever and turns ON. When the trailing edge of the document D passes and the lever is no longer pressed, the document presence sensor 46 no longer detects the document D and turns OFF. Therefore, based on the detection signal (ON / OFF) of the document presence sensor 46, the control unit 50 detects that the leading edge of the document D has passed the pair of transport rollers 35 and that the trailing edge of the document D has passed the pair of transport rollers 35. The detection results of the document presence sensor 46 detecting the leading edge and trailing edge of the document D are used to control the start and end timing of the reading operation of the reading unit 40 (40A, 40B), which will be described later. Furthermore, since the document presence sensor 46 can detect the leading and trailing edges of the document D, it can also detect the length of the document D in the transport direction Y, that is, the document size determined from that length, based on the transport distance of the document D from when the leading edge of the document D is detected until the trailing edge is detected. The document presence sensor 46 may be a non-contact sensor such as an optical sensor.

[0027] A reading unit 40 that reads an image is provided within the main body 12 of the image reading device 11. A pair of reading units 40 are provided on both sides of the transport path 29, at a position between the transport roller pair 35 and the discharge roller pair 36 in the transport direction Y. In this embodiment, the pair of reading units 40 comprises a first reading unit 40A that reads the front surface (bottom surface) of the document D transported along the transport path 29, and a second reading unit 40B that reads the back surface (top surface) of the document D transported along the transport path 29, and are arranged at positions slightly offset from each other in the transport direction Y, but a configuration may be such that one of the reading units is not provided.

[0028] The pair of reading units 40 are composed of a light source 41 that can irradiate light onto the document D being transported by irradiating the reading area SA with light, and an image sensor 42 that can read an image from the document D. In the normal reading mode, only the first reading unit 40A performs the reading operation and reads the front side of the document D, and in the double-sided reading mode, both the first reading unit 40A and the second reading unit 40B perform the reading operation and read both sides (front and back sides) of the document D.

[0029] The light source 41 is composed of, for example, an LED or a fluorescent lamp. The image sensor 42 receives light emitted from the light source 41 and reflected by the original D, converts the received light into an electrical signal, and outputs a pixel signal having a value corresponding to the amount of received light. In this manner, the image sensor 42 is a sensor that reads an image. The image sensor 42 is, for example, a linear image sensor. The image reading device 11 is capable of color scanning and monochrome scanning (grayscale scanning). Note that, hereinafter, the light source 41 and the image sensor 42 on the first reading unit 40A side may be referred to as the first light source 41A and the first image sensor 42A, and those on the second reading unit 40B side may be referred to as the second light source 41B and the second image sensor 42B.

[0030] The image sensor 42 is, for example, a contact-type image sensor in which a plurality of photoelectric conversion elements are arranged in a row along the main scanning direction X. Furthermore, the image sensor 42 is specifically a CMOS (Complementary Metal Oxide Semiconductor) image sensor. The image sensor 42 photoelectrically converts the light received by each photoelectric conversion element, and outputs a pixel signal having a value corresponding to the amount of received light.

[0031] Furthermore, a color reference plate 43 is disposed opposite the image sensor 42 across the transport path 29. The color reference plate 43 is disposed in an area that includes the area of the document D within the area to be read by the reading unit 40, but is larger than the area of the document D. Therefore, the color reference plate 43 is a component that enables determination of whether the image read by the reading unit 40 corresponds to the area of the document D. In other words, the color reference plate 43 is a background plate that is read as the background of the document D. The color reference plate 43 is also a component for obtaining a white reference value for shading correction, and a white reference plate that exhibits white or a gray reference plate that exhibits gray is used. As a result, the color reference plate 43 is read as a white reference image, and the white reference value is generated based on the read white reference image. In the case of a gray reference plate, it is read as the background (gray background) of the document and is also used to detect the position and area of the document D. Note that if a separate sensor for document area detection is provided, the color reference plate 43 is preferably a white reference plate. Furthermore, the color reference plate 43 is not limited to a plate shape, and any shape and color may be used as long as it is a reference member for obtaining a white reference value that serves as a luminance reference.

[0032] In a state where the original D is not present, the reading unit 40 can read the color reference plate 43, which is a background plate. Furthermore, when reading the original D, it is possible to read the margin at the leading end of the original D in the conveyance direction Y or the margin at the trailing end of the original D in the conveyance direction Y. Assuming that the color reference plate 43 or the margin at the leading or trailing end of the original D is not dirty, reading the margin of the color reference plate 43 or the original D makes it possible to read dirt such as paper powder or dust adhering to at least one of the light source 41 and the image sensor 42. In this embodiment, dirt detection is performed to detect dirt adhering to at least one of the light source 41 and the image sensor 42 based on read data obtained by reading the margin at the leading or trailing end of the color reference plate 43 or the original D. Details of the dirt detection process will be described later.

[0033] The image reading device 11 includes a control unit 50. The control unit 50 controls the image reading device 11 when a job to read an image from an original D is input based on an operation signal from an input unit 21 (see FIG. 1) operated by a user or a reading instruction signal (reading instruction) from a host device 100 (described later). When performing reading control, the control unit 50 controls the feed motor 37, the transport motor 38, and the reading unit 40 (40A, 40B), and processes image data based on the image read from the original D by the reading unit 40.

[0034] <Electrical configuration> Next, the electrical configuration of the image reading system 10 including the image reading device 11 will be described with reference to FIG.

[0035] As shown in FIG. 3 , the image reading system 10 includes an image reading device 11 that reads an original document D and an image reading control device 110 that controls the image reading device 11. The image reading system 10 includes a blank page removal function that removes blank pages from the image of the original document D read by the image reading device 11. The image reading control device 110 is built into a host device 100 that is communicatively connected to the image reading device 11. A computer 120 in the host device 100 is installed with a program including a scan driver program. The image reading control device 110 is implemented by software configured by the computer 120 that executes this program. The image reading control device 110 may be a scan driver or support software for the image reading device 11. The image reading control device 110 displays various screens on the display unit 102 in response to instructions from the input unit 101 of the host device 100, and causes the image reading device 11 to perform a scan under specified scan conditions. Details of the blank page removal function of the image reading system 10 will be described later.

[0036] First, the electrical configuration of the image reading device 11 will be described. The image reading device 11 is connected to a host device 100 via a communication cable. The host device 100 is, for example, a personal computer (hereinafter also referred to as a "PC"), and includes an input unit 101 and a display unit 102 electrically connected to its main body. The host device 100 includes a reading driver consisting of software that has the function of issuing reading instructions to the image reading device 11 by installing a reading driver program therein. Note that the host device 100 is not limited to a PC, and may also be a smart device such as a personal digital assistant (PDA), a tablet PC, or a smartphone.

[0037] When the user operates the input unit 21 or the input unit 101 of the host device 100, setting conditions for the image reading process are set. That is, the setting conditions are set by user input. The setting conditions include reading conditions such as document size, reading resolution, reading color, single-sided reading / double-sided reading, etc., and storage conditions such as the storage format, transfer method, and storage destination of the read data (image data). Document sizes include, for example, A4 size and B5 size, reading resolutions include, for example, 300 dpi / 600 dpi, and reading colors include monochrome (grayscale) / color. Storage formats include PDF format, PDF / A format, JPEG format, GIF format, TIFF format, etc. In addition, transfer methods include transfer to the host device 100 and email transfer, and the address of the storage destination is specified as the storage destination.

[0038] The image reading device 11 has a built-in control unit 50 that controls the device overall. The control unit 50 has a computer 60 consisting of a microprocessor or the like. The computer 60 has a volatile memory 61 and a non-volatile memory 62 as an example of a storage unit. The non-volatile memory 62 stores various programs including the program PR shown in the flowchart of FIG. 13. The non-volatile memory 62 also stores various table data such as a first management table SD1 (FIG. 5), a second management table SD2 (FIG. 7), and a blank paper determination table BT (FIG. 8) that the computer 60 refers to while executing the program PR.

[0039] The control unit 50 also has an input interface 63 (hereinafter also referred to as "input IF63") that inputs various data and signals from the host device 100, and an output interface 64 (hereinafter also referred to as "output IF64") that outputs the read data read by the image reading device 11 to the host device 100.

[0040] The control unit 50 also includes a timing generator 65 (hereinafter also referred to as "TG65") that outputs pulse signals that define the timing of various operations, including readout operations, to the image sensors 42A and 42B. The control unit 50 also includes an analog front end 66 (hereinafter also referred to as "AFE66") that performs analog-to-digital conversion (A / D conversion) on pixel signals input from the image sensors 42A and 42B.

[0041] The computer 60 includes functional parts made up of software configured internally by executing various programs including the program PR, such as a main control unit 70, a transport control unit 71, a reading control unit 72, and an image processing unit 73. The main control unit 70 comprehensively controls the image reading device 11 and issues instructions to each unit 71 to 73. Note that some functional units, such as the image processing unit 73, may be configured in part by hardware.

[0042] The transport control unit 71 drives and controls the feed motor 37 and the transport motor 38 in accordance with instructions from the main control unit 70. The feed motor 37 drives the feed roller 33 to rotate, thereby feeding a stack of multiple documents D (hereinafter also referred to as "document stack D") set on the document support 13 into the main body 12 one by one, starting from the bottom one. The feed motor 37 drives and rotates the drive roller 34A, one of the feed roller pair 34, and the transport motor 38 drives and rotates the separation roller 34B, the other. In particular, the transport control unit 71 drives and controls the feed motor 37 and the transport motor 38 so that the documents D are transported through a reading area SA along the transport path 29 at a reading speed corresponding to the reading resolution (e.g., 300 / 600 dpi). For example, when the reading resolution is relatively low (for example, 300 dpi), the document D is transported at a high speed, and when the reading resolution is relatively high (for example, 600 dpi), the document D is transported at a low speed.

[0043] The reading control unit 72 controls the reading unit 40 via the TG65, causing the reading unit 40 to read the image of the document D. In particular, the reading control unit 72 outputs to the TG65 a pulse signal that specifies the operation timing of various operations, including the reading operation, for the image sensor 42, and controls the light emission of the light source 41 via a light source driving unit (not shown), causing the light source 41 to irradiate the reading area SA with light.

[0044] When the digital signal of the image read by the reading unit 40 is input via the AFE 66, the image processing unit 73 temporarily stores image data based on the input digital signal, and performs known correction processing such as shading correction on the stored image data to generate image data of the original D. The image processing unit 73 performs various corrections such as gamma correction in addition to shading correction, and outputs the corrected image data to the host device 100 via the output IF 64 and a communication cable (not shown).

[0045] Fig. 3 shows an image reading system. The image reading system 10 shown in Fig. 3 includes an image reading device 11 and a host device 100 as an example of an image reading control device that is communicatively connected to the image reading device 11. When reading an original D with the image reading device 11, the user can operate the input unit 21 of the image reading device 11 to instruct the image reading device 11 to start reading, or can operate the input unit 101 of the host device 100 to instruct the image reading device 11 to start reading.

[0046] Therefore, the image reading control device 110 included in the host device 100 similarly has some of the functions of the control unit of the image reading device 11. Specifically, the image reading control device 110 similarly has some of the functions configured by software included in the control unit 50 of the image reading device 11. For example, the image reading control device 110 similarly has the functions of the main control unit 70 in the control unit 50 of the image reading device 11. Details of the image reading control device 110 will be described later.

[0047] 3, the control unit 50 of the image reading device 11 has various functional parts configured by software that are configured by executing a program on the computer 60. For example, the main control unit 70 and part of the image processing unit 73 are configured by software.

[0048] 3, the main control unit 70 has a display control unit 76, a blank page removal setting unit 77, a blank page removal level setting unit 78, and a preview setting unit 79. The image processing unit 73 also has an OCR (optical character recognition) 86, a blank page determination unit 87 as an example of a determination unit, and a data generation unit 88.

[0049] In this embodiment, the display control unit 76, blank page removal setting unit 77, blank page removal level setting unit 78, and preview setting unit 79 in the main control unit 70, and the OCR 86, blank page determination unit 87, and data generation unit 88 in the image processing unit 73 are configured by software. These software functional units in the main control unit 70 are responsible for a setting function for setting conditions for displaying a blank page preview screen 130 (FIG. 12) and a setting function for setting conditions for displaying a document preview screen 140 (FIG. 11). Furthermore, these software functional units in the image processing unit 73 are responsible for a display function for displaying the blank page preview screen 130 and a display function for displaying the document preview screen 140.

[0050] In this embodiment, the host device 100 is also capable of displaying a blank preview screen 130 (FIG. 12) and a document preview screen 140 (FIG. 11) on the display unit 102. The host device 100 includes an image reading control device 110 configured by software. The image reading control device 110 is configured by a computer 60 that executes a program installed in the host device 100. This program may be a scanner driver program, or may be a program for enhancing the functionality of the image reading device 11 that is separate from the scanner driver program.

[0051] In this embodiment, the display control unit 76 controls the display content of the display unit 22. When the user inputs an operation signal from the input unit 21, the display control unit 76 performs display control to display a setting screen corresponding to the operation signal on the display unit 22. In response to the operation signal from the input unit 21, the display control unit 76 displays various setting screens, such as a job selection screen 121 (see FIG. 11) including a first setting screen 91 shown in FIG. 4 and a second setting screen 92 shown in FIG. 6, for example.

[0052] Furthermore, when the blank page removal function that can be set on the first setting screen 91 is ON (enabled), the display control unit 76 displays a blank page preview screen 130 (FIG. 12) that previews only the images of blank pages that have been determined to be blank pages among the images of the document stack D that have been read after scanning is completed. Furthermore, when the preview function that can be set on the first setting screen 91 is ON (enabled), the display control unit 76 displays a document preview screen 140 (see FIG. 11) that previews the images of the document stack D that have been read after the job is completed.

[0053] The user can display a job selection screen 121 (FIG. 11), a first setting screen 91 (FIG. 4), a second setting screen 92 (FIG. 6), etc. by operating the touch panel to select a lower-level screen from the menu displayed on the display unit 22. The user can perform various settings, including setting the reading conditions and enabling / disabling the blank page preview function and the preview function, by selecting options, etc., on the various screens displayed on the display unit 22 using the touch panel.

[0054] When the blank paper removal setting unit 77 receives an operation signal for selecting ON / OFF of the blank paper removal function on the first setting screen 91, it sets ON / OFF of the blank paper removal function in accordance with the operation signal.

[0055] When the user operates a pointing device such as a mouse on the first setting screen 91 or the blank page preview screen 130 to select a desired value from the settable range of the blank page removal level and then inputs a signal to confirm the value from the input unit 21, 101, the blank page removal level setting unit 78 sets the input value as the blank page removal level. The user operates the input unit 21, 101 to select, for example, a blank page removal level of "15" and then confirms the selection. When the blank page removal level setting unit 78 receives the value "15" and the confirmation signal, it updates the setting of the blank page removal level to "15." The blank page removal level value is a parameter that determines a threshold value used in blank page determination by the blank page determination unit 87 to determine whether or not an image on the document D is a blank page when the blank page removal function is ON.

[0056] The preview setting section 79 sets ON / OFF of a preview screen display function that displays a document preview screen 140 (see FIG. 11). <First setting screen 91> The first setting screen 91 shown in FIG. 4 is a setting screen for selecting whether the blank page removal function is ON or OFF, setting the blank page removal level value, and selecting whether the preview screen display function is ON or OFF. As shown in FIG. 4, the first setting screen 91 includes a selection field 93 for selecting whether the blank page removal function is ON or OFF, a first selection field 931 for selecting whether to enable (ON) the textless document display function, which becomes selectable when the blank page removal function is ON, and a second selection field 932 for selecting whether to enable (ON) the text-containing document hide function. The first setting screen 91 also includes a selection field 94 for selecting whether to enable (ON) the preview screen display function. The blank page removal function performs a blank page determination to determine whether the scanned image of the document stack D is a blank document. If an image of a blank document is included, the blank document image is removed before generating a scanned file. Therefore, if the user wants to automatically remove blank document images from the document stack D, the user selects the selection field 93 to enable (ON) the blank page removal function.

[0057] The first setting screen 91 is provided with a slider 93A as an operation section that allows the user to select the blank page removal level by sliding the slider 93A. When the blank page removal function is enabled, the user can adjust the value of the blank page removal level by sliding the slider 93A. In this example, the blank page removal level is provided with values from 0 to 30, for example, and the user sets one value from within this range. In the example shown in FIG. 4, the blank page removal level is set to "15." For example, for pure white paper, the blank page removal level is set to a low value, and for colored paper or recycled paper, the blank page removal level is set to a higher value than for pure white paper.

[0058] Furthermore, when the blank page removal function is ON, a blank page preview screen 130 (FIG. 12) is displayed, which previews images of blank page removal candidates of document D that will be removed as blank pages after scanning is complete. The user can check the images of the blank page removal candidates on the blank page preview screen 130, and if there are any images that the user does not want to remove as blank pages, they can switch from blank page removal candidates to non-removal candidates. In this embodiment, with the default setting of the blank page preview screen 130, images of documents without text are not previewed as blank page removal candidates even if they are determined to be blank pages, and documents with text are previewed as blank page removal candidates if they are determined to be blank pages.

[0059] However, some users want to confirm whether or not blank pages can be removed even for documents without text. Also, even for documents with text, there is no need to confirm images that can clearly be removed as blank documents, and so some users do not want to display them on the blank page preview screen 130. For this reason, the first setting screen 91 shown in FIG. 4 has a selection section 931 for selecting ON / OFF of a "textless document display function" that displays documents without text. The first setting screen 91 also has a selection section 932 for selecting ON / OFF of a "text-containing document hide function" that does not display documents with text.

[0060] Furthermore, when the preview screen display function selection section 94 is ON, an original preview screen 140 (FIG. 11) is displayed after the job is completed, showing a preview of all original images. On this original preview screen 140, the user can check the image quality and color of the scanned image, whether there are any unnecessary blank originals, etc. For example, if there are any unnecessary blank originals, the user can remove the images of the unnecessary blank originals by operating the original preview screen 140.

[0061] After selecting the selected section, setting the blank page removal level, and selecting the preview screen display function on the first setting screen 91, the user operates the OK button 95 to register those settings. This registration of the settings is performed by each of the setting sections 77 to 79, which input ON / OFF information for each selected section when an OK signal is input.

[0062] Each setting unit 77 to 79 manages the registered setting contents using a first management table SD1 shown in FIG. 5. As shown in FIG. 5, the first management table SD1 manages the ON / OFF of the blank page removal function, and when the blank page removal function is ON, the first management table SD1 manages the ON / OFF of the no-text document display function and the ON / OFF of the text document hide function. Also, when the blank page removal function is OFF, both the no-text document display function and the text document hide function are turned OFF. Also, the preview screen display function, whether ON or OFF, is managed. For example, when the OK button 95 is operated with the setting contents of the first setting screen 91 shown in FIG. 4, all four functions are turned ON in the first management table SD1.

[0063] Based on the settings in these setting sections 77 to 79, the main control section 70 refers to the first management table SD1 shown in Fig. 4 stored in the nonvolatile memory 62 to manage the presence or absence of the blank page removal function, the presence or absence of the textless document display function, the presence or absence of the textual document display function, and the presence or absence of the preview screen display function. Note that the selectable sections 931, 932 and slider 93A related to the blank page removal function on the first setting screen 91 in Fig. 4 are also provided on the blank page preview screen 130 (Fig. 12), so all or part of these may be eliminated.

[0064] <Second setting screen> The second setting screen will be described with reference to FIG. 6. The second setting screen 92 shown in FIG. 6 is a setting screen for selecting one of four settings: normal scan, AFM job, continuous job, and AFM & continuous job, and enabling the selected scan format. Here, AFM stands for auto feed mode. When AFM is enabled (ON), when a stack of documents D is placed on the document support 13, the detection of the placement triggers automatic scanning of the documents D. A continuous job is a scan mode selected when there are multiple sets of documents to be read as a single file. When a continuous job is enabled, when a document D is placed on the document support 13, the job is executed and scanned. When the next document D is then placed on the document support 13, the next document is scanned. Multiple sets of documents scanned in continuous scanning are read as a single file. When both AFM and continuous job are selected, AFM & continuous job is a scan mode that combines the functions of both AFM and continuous job.

[0065] The second setting screen 92 has selection fields 96-98, e.g., check boxes, that can be individually checked for normal scan, AFM, and continuous job. Specifically, the second setting screen 92 has a selection field 96 for selecting normal scan, a selection field 97 for selecting AFM, and a selection field 98 for selecting continuous job. The user can simultaneously select both the AFM and continuous job selection fields 97, 98. By selecting both, both modes are enabled, and the AFM & continuous job mode is set. The user can individually select and set each of the normal scan, AFM, continuous job, and AFM & continuous job modes by operating the input unit 21 of the image reading device 11 or the input unit 101 of the host device 100. Selecting the OK button 99 on the second setting screen 92 sets one mode according to the scan format selected on the second setting screen 92.

[0066] <Second management table> Next, we will explain the second management table SD2 shown in Fig. 7. The second management table SD2 manages the timing of displaying the blank page preview screen for each scan format and the timing of reflecting the blank page removal level changed on the blank page preview screen 130 (Fig. 12).

[0067] The computers 60, 120 refer to the second management table SD2 based on the scan format selected on the second setting screen 92 to obtain the display timing for displaying the blank page preview screen 130. The computers 60, 120 also refer to the second management table SD2 based on the scan format selected on the second setting screen 92 to obtain the reflection timing for reflecting the setting value of the blank page removal level.

[0068] As shown in FIG. 7, in the case of a normal scan, the blank page preview screen 130 is displayed "after the job is completed," and the changed setting value of the blank page removal level is reflected "from the next scan job." In the case of an AFM, the blank page preview screen 130 is displayed "after scanning of the document stack is completed," and the changed setting value of the blank page removal level is reflected "from the scan of the next document stack." In the case of a continuous job, the blank page preview screen 130 is displayed "after scanning of the document stack is completed," and the changed setting value of the blank page removal level is reflected "from the scan of the next document stack." Furthermore, in the case of an AFM & continuous job, the blank page preview screen 130 is displayed "after scanning of the document stack is completed," and the changed setting value of the blank page removal level is reflected "from the scan of the next document stack."

[0069] In this embodiment, when the blank page removal function is ON, the display control unit 76 displays a blank page preview screen 130 (FIG. 12) on the display units 22, 102 at the display timing corresponding to the scan format at that time. Also, on the blank page preview screen 130, a slider 133A (see FIG. 12), which will be described later, is slid by operating the input units 21, 101 to change the setting value of the blank page removal level, and then when the complete button 138 is operated, the setting value of the blank page removal level after the change is confirmed. After this confirmation, when the timing comes to reflect the setting value of the blank page removal level corresponding to the scan format, the confirmed changed blank page removal level is reflected as the setting value.

[0070] 3 inputs, as operation signals from the input units 21, 101, coordinate values of the adjustment position when the user adjusts the blank paper removal level by operating the input units 21, 101 on the first setting screen 91 and the blank paper preview screen 130, and acquires the setting value of the adjusted blank paper removal level from the value corresponding to the input coordinate values. After acquiring the blank paper removal level, the blank paper removal level setting unit 78 updates the setting of the blank paper removal level when it receives an operation to confirm the value.

[0071] As shown in FIG. 8 , the blank page determination table BT has 30 blank page removal levels, ranging from "1" to "30." The blank page removal level is a setting value that determines a threshold for removing an image of a document D as a blank page. For example, if the blank page removal level is "1," any color in the background will be removed as a blank page. For example, a small value is set for the blank page removal level for a document D with a pure white background. A larger value is set for the blank page removal level for a document D with a background color such as light gray, light red, light blue, or cream than for a document D with a pure white background. Furthermore, recycled paper may contain fine paper fibers that are darker than the background color, so a larger value is set for the blank page removal level than for a document D with a pure white background. The user can adjust the value of the blank page removal level according to the background color and paper quality of the document D, thereby setting the blank page removal level so that, for example, only blank documents with no printed content are removed as blank pages. This makes it possible to avoid the inconvenience of not removing a blank page even though it is a blank document, or not removing a document D with a very small amount of printing as a blank page. The number of blank page removal levels is not limited to 30 levels, but may be 10 levels, 20 levels, 50 levels, or even 2 levels or 5 levels, and the number of levels can be set appropriately according to user needs and the blank page removal accuracy required of the image reading device 11.

[0072] In the blank page determination table BT shown in FIG. 8, a threshold value PS0 is set for each blank page removal level. The blank page determination unit 87 performs blank page determination using the threshold value PS0 corresponding to the blank page removal level set by the user. The higher the blank page removal level, the larger the threshold value PS0. The blank page determination unit 87 determines that a page is blank if the print area pixel count PN, which is the number of pixels in the print area PA in the histogram HD, is equal to or less than the threshold value PS0 (PN≦PS0). On the other hand, the blank page determination unit 87 determines that a page is not blank if the print area pixel count PN exceeds the threshold value PS0 (PN>PS0).

[0073] <Configuration of image processing unit> Next, a detailed configuration of the image processing unit 73 will be described with reference to Fig. 9. Note that Fig. 9 shows the image processing unit 73 in the image reading device 11, but the image reading control device 110 in the host device 100 also has a similar software configuration of the image processing unit 73.

[0074] The image processing unit 73 includes an RGB buffer 81 , a YUV generation unit 82 , a YUV buffer 83 , a histogram generation unit 84 , and a histogram buffer 85 . The image processing unit 73 acquires the read data obtained by reading the original document D by the first image sensor 42A and the second image sensor 42B constituting the reading unit 40 as RGB data via the AFE 66. The image processing unit 73 stores the RGB data in the RGB buffer 81. That is, the image processing unit 73 receives the read data obtained by reading the original document D by the reading unit 40 as a digital signal from the AFE 66, and stores image data in RGB format based on the digital signal in the RGB buffer 81.

[0075] The YUV generation unit 82 generates YUV data from the RGB data read out from the RGB buffer 81. The YUV generation unit 82 stores the generated YUV data in the YUV buffer 83. In other words, the YUV generation unit 82 generates image data in the YUV format from image data in the RGB format and stores the image data in the YUV buffer 83.

[0076] The histogram generation unit 84 acquires RGB data from the RGB buffer 81 and Y data from the YUV buffer 83, and generates a histogram HD (see FIG. 10) of four colors, RGBY. The histogram generation unit 84 temporarily stores the data of the histogram HD of four colors, RGBY, in a histogram buffer 85.

[0077] 9 includes a display control unit 76, an OCR 86, a blank page determination unit 87, and a data generation unit 88, which are software components that are also included in the image reading control device 110. The display control unit 76 includes a preview display processing unit 761 and a display switching unit 762. The data generation unit 88 includes a blank page removal processing unit 881 and a file format conversion unit 882. When the display control unit 76, the OCR 86, the blank page determination unit 87, and the data generation unit 88 operate within the image reading device 11, processing proceeds according to the data flow shown in FIG. 9. When they operate within the image reading control device 110, on the other hand, necessary data including image data of the document D read by the image reading device 11 is transmitted from the image reading device 11 to the image reading control device 110 in the host device 100. Then, the display control unit 76, OCR 86, blank paper determination unit 87, and data generation unit 88 in the image reading control device 110 perform processing similar to that of the display control unit 76, OCR 86, blank paper determination unit 87, and data generation unit 88 in the image processing unit 73 of Figure 9 based on the necessary data including image data received from the image reading device 11.

[0078] Whether the image reading device 11 or the image reading control device 110 performs the above process depends on whether the user operates the input unit 21 of the image reading device 11 or the input unit 101 of the host device 100 to execute the job. In the latter case, the image data and histogram HD data obtained by reading the stack of originals D are transmitted to the host device 100 via the output IF 64. The image data is transmitted in a state before blank pages are removed. The image data may be RGB image data, YUV image data, or image data compressed to a predetermined file format. Any image data may be used as long as it can generate the blank page preview screen 130, the original preview screen 140, and ultimately a file in a predetermined file format specified by the user's output conditions. If the histogram generation unit 84 is software, the image reading control device 110 may also include the histogram generation unit 84. In this case, the image reading control device 110 may generate the histogram HD using the image data received from the image reading device 11 using its own histogram generation unit 84.

[0079] The image reading control device 110 also temporarily stores image data and the like received from the image reading device 11 in a buffer. The image reading control device 110 uses a portion of the memory of the computer 120 in the host device 100 as a buffer similar to that shown in FIG. 9. That is, when receiving RGB image data, the image reading control device 110 has an RGB buffer 81 similar to that shown in FIG. 9. When receiving YUV image data, the image reading control device 110 has a YUV buffer 83 similar to that shown in FIG. 9. Furthermore, the image reading control device 110 also has a histogram buffer 85 similar to that shown in FIG. 9 for temporarily storing received or generated histogram HD data. Therefore, within the image reading control device 110, the data flow when the display control unit 76, OCR 86, blank page determination unit 87, and data generation unit 88 are activated and perform their respective processes is as shown in FIG. 9. The image reading control device 110 also has a buffer (not shown) for storing files in a predetermined file format generated by the file format conversion unit 882. In this buffer, files received from the image reading device 11 and files generated by the file format conversion unit 882 in the image reading control device 110 are stored.

[0080] The functions of each part of the software shared by the image reading device 11 and the image reading control device 110 will be described in detail below. The OCR 86 extracts characters from the image data of the document D read by the reading unit 40, i.e., the RGB image data read from the RGB buffer 81 or the YUV image data read from the YUV buffer 83, and converts the extracted characters into text data. To this end, the OCR 86 has a character recognition function that recognizes characters (text) in the image data, and a character code conversion function that converts characters recognized by the character recognition function into text data (character code). The blank page removal process of this embodiment uses the character recognition function, one of the multiple functions of the OCR 86. Character recognition result information obtained by the OCR 86 in the character recognition process is sent to the display control unit 76.

[0081] The blank page determination unit 87 shown in FIGS. 3 and 9 determines whether each page of the document D is a blank page based on the image data of the document D. Based on the image data of the scanned document D, the blank page determination unit 87 determines images that satisfy the blank page removal level of the blank page removal function as blank page removal candidates, and determines images that do not satisfy the blank page removal level as non-removal candidates. The blank page determination unit 87 performs blank page determination, regarding an image of the document D as a blank document when the number of pixels having a predetermined density, such as characters, in the document is equal to or less than a threshold value corresponding to the set value of the blank page removal level. The blank page determination unit 87 references the blank page determination table BT shown in FIG. 8 to obtain a threshold value PS0 corresponding to the currently set blank page removal level. For example, if the current blank page removal level is "15" in the blank page determination table BT shown in FIG. 8, the blank page determination unit 87 obtains a threshold value PS0=10000 corresponding to the blank page removal level "15."

[0082] 3 and 9 uses a histogram of the four RGBY colors in the image data of the document D to calculate the print area pixel number PN, which is the number of pixels in the print area PA, which is defined as a density area that is a predetermined density or more darker than the background color of the document D. If the print area pixel number PN is equal to or less than a threshold value PS0 (PN≦PS0), the blank page determination unit 87 determines that the document is a blank page. On the other hand, if the print area pixel number PN exceeds the threshold value PS0 (PN>PS0), the blank page determination unit 87 determines that the document is not a blank page.

[0083] <Histogram> Here, a blank page determination method performed by the blank page determination unit 87 using the histogram HD will be described with reference to Fig. 10. The histogram generation unit 84 shown in Fig. 9 generates the histogram HD shown in Fig. 10 for each page based on the read data SD for each sheet of original. The histogram generation unit 84 generates the histogram HD of the four colors RGBY described above and shown in Fig. 10. The horizontal axis of the histogram HD in Fig. 10 represents the luminance value, which takes values from 0 to 255 in 256 gradations, for example. The vertical axis of the histogram HD represents the number of pixels.

[0084] In the histogram HD for each page based on the scanned data for each document sheet, the peaks of the four RGBY colors appear at brightness values of around 180 to 230, which represent the background color of the paper of document D. The background color may be, for example, white, light gray, cream, light blue, or light red.

[0085] In a one-page histogram HD based on the scanned data of a normal document D on which characters and images are printed, a peak appears in the brightness value corresponding to the background color of the paper of the document D, and pixels of printed portions such as text and images appear in an area with a brightness value lower than a brightness threshold that is a predetermined offset amount lower than the peak of the background color.

[0086] Next, a method for determining whether document D is a blank document by blank document determination unit 87 will be described with reference to Fig. 10. When document D is a blank document, the histogram HD shown in Fig. 10 has only a peak in the background color, and there are almost no pixels in the print area PA that have a brightness value lower than the peak in the background color.

[0087] A typical document D has characters and images printed in a color darker than the background color of the paper. As shown in FIG. 10, the area of brightness values that the pixels of printed characters, images, etc. can take is defined as the print area PA. The print area PA is an area below a brightness threshold LS, which is a value obtained by offsetting the background color brightness value GC, which is indicated by the peak brightness values of the four colors RGBY that represent the peak of the background color of document D, by a predetermined offset amount ΔOF toward the lower brightness value side (to the left in FIG. 10). In other words, the print area PA is an area ranging from brightness values 0 to LS.

[0088] If a document is blank, there are no or very few pixels with a luminance value in the print area PA. The blank page removal level is an index that indicates the degree to which the print area pixel count PN, which is the number of pixels in the print area PA, is small. Therefore, a threshold value PS0 corresponding to the blank page removal level is set in the blank page determination table BT. The blank page determination unit 87 determines that the image of the document D is a blank page if the print area pixel count PN is equal to or less than the threshold value PS0 corresponding to the blank page removal level. Therefore, in this embodiment, the blank page determination unit 87 identifies the print area PA from the histogram HD of the image data of the document D based on the background color luminance value GC, counts the print area pixel count PN, which is the number of pixels in the identified print area PA, and determines whether the print area pixel count PN is equal to or less than the threshold value PS0 corresponding to the blank page removal level. The blank page determination unit 87 determines that the document is blank if the print area pixel count PN is equal to or less than the threshold value PS0, and determines that the document is not blank if the print area pixel count PN is not equal to or less than the threshold value PS0. This blank page determination result is used to generate a blank page preview screen 130 (FIG. 12), which will be described later. For this reason, blank page determination result information, which the blank page determination unit 87 performed on the image data of document D for each page, is sent to the display control unit 76. Note that, for example, since the peak position (pixel value) GC differs for each color, the upper limit value of the print area PA also differs for each color. Note that in this embodiment, the offset amount ΔOF is a common value for each color, but a different offset amount ΔOF may be set for each color.

[0089] The display control unit 76 performs display control to display various screens from before scanning starts to the end of a job when the image reading device 11 executes one job. For example, if the blank page removal function is ON, the display control unit 76 displays a blank page preview screen 130 (see FIG. 12) on the display unit 22, 102 when scanning ends, and if the preview screen display function is ON, the display control unit 76 displays a document preview screen 140 on the display unit 22, 102 when the job ends.

[0090] <Display screen transition> Here, with reference to FIG. 11 , transitions of screens displayed on the display unit 22, 102 by the display control unit 76 will be described. Before and during execution of a job, the display unit 22, 102 displays a job selection screen 121, a job execution screen 122, and a scanning screen 123 in this order. The job selection screen 121 is a screen for selecting a job. On this job selection screen 121, scanning conditions such as scanning resolution and scanning color (color / grayscale / monochrome) and output conditions including the user's desired file format are set. Furthermore, the job selection screen 121 includes a first setting screen 91 and a second setting screen 92 as lower-level screens. Therefore, settings such as selecting the scan format, turning the blank page removal function on / off, and turning the preview display function on / off can also be performed on the job selection screen 121 and its lower-level screens. Once the job setting conditions are confirmed, the screen transitions to the job execution screen 122. A scan start button (not shown) is displayed on the job execution screen 122, and the user operates the scan start button, for example, by operating a touch panel, to instruct the image reading device 11 to start scanning. While scanning is in progress, a scan in progress screen 123 is displayed on the display unit 22, 102 to notify that scanning is in progress.

[0091] Blank page preview screen 130 and document preview screen 140 (hereinafter simply referred to as "preview screen 140") are displayed at a predetermined display timing after scanning is completed if their respective display functions are enabled. That is, when scanning is completed, blank page preview screen 130 is displayed if the blank page removal function is ON, and blank page preview screen 130 is not displayed if the blank page removal function is OFF. Also, when the job is completed, preview screen 140 is displayed if the preview screen display function is ON, and preview screen 140 is not displayed if the preview screen display function is OFF. Note that when both the blank page removal function and the preview screen display function are ON, blank page preview screen 130 is displayed in preference to preview screen 140.

[0092] 9 includes the preview display processing unit 761 described above as a processing unit that performs display processing to display the blank preview screen 130 and the preview screen 140. The display control unit 76 also includes the display switching unit 762 described above as a processing unit that switches the display mode of the selected image to a selection state in which the blank page removal candidate or the non-removal candidate is selected when the user performs an operation to select an image that the user wants to use as a blank page removal candidate or a non-removal candidate from among the images previewed on the blank preview screen 130.

[0093] First, the preview display processing unit 761 shown in FIG. 9 will be described. The preview display processing unit 761 displays a selectable preview of at least some of the images of the scanned original document D on the display units 22, 102. In this example, the preview display processing unit 761 displays a blank page preview screen 130 on the display units 22, 102, previewing at least some of the images of the original document D that have been determined by the blank page determination unit 87 to be blank page removal candidates. The preview display processing unit 761 generates screen data for displaying the blank page preview screen 130. The preview display processing unit 761 acquires the blank page determination result from the blank page determination unit 87, and identifies the blank page removal candidate images BP (see FIG. 12) based on the blank page determination result. The preview display processing unit 761 reads out the image data of the blank page removal candidates from the image data of the original document D stored in the buffers 81, 83, generates low-resolution image data of the blank page removal candidates from the read image data of the blank page removal candidates, and performs screen generation processing including processing for incorporating this low-resolution image data into the display area of the screen, thereby generating the screen data. 12 on the display units 22, 102. Note that some images, such as images of documents without text or images of documents with text when the text document hiding mechanism is enabled, are not included in the preview image even if they are candidates for blank page removal.

[0094] <Blank preview screen> Here, the blank preview screen 130 will be described with reference to FIG. 12 is displayed on the display unit 22, 102 at the aforementioned predetermined display timing after the scanning of the document D is completed. The blank page preview screen 130 is a setting screen that allows the user to preview blank pages that are images of blank page removal candidates that have been determined to be blank documents from among the images of the scan results, and also allows the user to change the setting value of the blank page removal level while checking the image BP of the blank page removal candidate. In this way, the blank page preview screen 130 is a setting screen that the user uses to view the image BP of the blank page removal candidate and change the setting value of the blank page removal level.

[0095] For this reason, the blank page preview screen 130 is displayed at a predetermined timing after scanning is completed. Specifically, there are two types of timing for displaying the blank page preview screen 130, depending on the scanning format. One is when the continuous feed mode is being executed, in which the document stack D for one job can be set on the document support 13 in multiple batches and scanned, and the blank page preview screen 130 is displayed each time scanning of a single set of document D is completed. The other is when the blank page preview screen 130 is displayed at the timing at which the job is completed. For this reason, when the continuous feed mode is being executed, in which the documents for one job are set in multiple batches and continuously read as a single job, the blank page removal level can be changed even in the middle of the job when scanning of a single set of document is completed. In this embodiment, these two timings are sometimes collectively referred to as "when scanning is completed."

[0096] As shown in FIG. 12, the blank page preview screen 130 includes a preview display area 131 in which a preview of an image BP that is a candidate for blank page removal is displayed, and a page information display area 132 that displays page information related to the image that is a candidate for blank page removal. The blank page preview screen 130 also includes a removal level adjustment area 133 that can adjust the blank page removal level. The removal level adjustment area 133 includes a slider 133A as an operation area that can be operated on the screen by inputting data from the input unit 21, 101. That is, the removal level adjustment area 133 includes the slider 133A that is slid to a position corresponding to the value of the blank page removal level. The slider 133A can be slid by operating the input unit 21, 101 to adjust the value of the blank page removal level depending on the position to which it is slid. In the example shown in FIG. 12, sliding the slider 133A leftward decreases the value of the blank page removal level, whereas sliding the slider 133A rightward increases the value of the blank page removal level.

[0097] Furthermore, blank page preview screen 130 includes a first selection section 134 that allows the user to select whether to display an image of a textless document as a blank page removal candidate, and a second selection section 135 that allows the user to select whether to not display a textual document as a blank page removal candidate. First selection section 134 and second selection section 135 are, for example, check boxes, but may also be display components such as radio buttons, pull-down selection sections, or push buttons.

[0098] Furthermore, the blank page preview screen 130 includes an enlarged display section 136 in which a selected image from among the blank page removal candidate images BP is enlarged and displayed. One of the blank page removal candidate images BP displayed in the preview display area 131 is in a selected state selected by the user through operation of the input section 21, 101, and an enlarged image ZP of the selected blank page removal candidate image BP is displayed in the enlarged display section 136. In addition, the preview display processing section 761 displays, on the display section 22, 102, a removal level adjustment section 133 that allows adjustment of the blank page removal level.

[0099] 16 on the display units 22, 102 in a state where both the image BP and the removal level adjustment unit 133 are arranged so as to be visible. The user can check the change in the display of the image BP that is a candidate for blank page removal while operating the removal level adjustment unit 133 on the blank page preview screen 130, and adjust the blank page removal level appropriately.

[0100] Furthermore, when an image BP that is a candidate for blank page removal is selected by a touch operation on the input unit 21 or a pointing device such as a mouse that constitutes the input unit 101, the image BP is highlighted. In the example shown in FIG. 12, the selected image BPs of pages 3 and 4 are highlighted by a highlighting unit 137 that is made up of highlighting frames that surround each of the selected images. For example, the highlighted image BP is an image that the user has selected as a candidate for blank page removal. When the user selects an image BP as a candidate for blank page removal, the selected image BP is highlighted by a first highlighting unit 137, and the page information in the page information display unit 132 that corresponds to the selected image BP is highlighted by a second highlighting unit 132A, such as a display frame that surrounds it. This allows the user to confirm at a glance the image BP that the user has selected as a candidate for blank page removal and its page information.

[0101] Here, a configuration may be adopted in which a selection section (not shown) is provided that selects all of the image BPs that are candidates for blank page removal, and a non-removal candidate is selected from among all of the selected images BP, and the highlighted image is selected by canceling the highlighted display state. In this way, by operating the input section 21, 101 to select an image BP that is a candidate for blank page removal, a switching operation is performed to switch the display state of the image BP to a selected state in which a blank page removal candidate or a non-removal candidate is selected. Note that the blank page preview screen 130 has a display image number selection function that can select the number of images BP to be displayed in the preview display area 131, and a page turning function that can turn the page of the preview display area 131 forward or backward.

[0102] The blank page preview screen 130 also includes a Done button 138 and a Discard button 139. The user checks the image BP of the blank page removal candidate previewed on the blank page preview screen 130 and, as necessary, operates the input unit 21, 101 to switch the display of the image BP between the blank page removal candidate and the non-removal candidate, thereby setting the image blank page removal candidate and the non-removal candidate as desired. For example, the user selects an image BP to change the blank page removal candidate, and as shown in FIG. 12, the image BP of the blank page removal candidate is set in a selected state (highlighted). Then, the user operates the Done button 138 by operating the input unit 21, 101. Operating the Done button 138 corresponds to a confirmation operation that confirms the blank page removal candidate and the non-removal candidate on the blank page preview screen 130. The Discard button 139 is operated when the user wishes to discard the image data of the scanned document D. After checking the image BP of the blank page removal candidate, the user may wish to rescan the document D. In this case, the user operates the Discard button 139 to discard the image data of the document D that is no longer needed.

[0103] Next, a preview display processing unit 761 that displays the blank page preview screen 130, a display switching unit 762 that switches the display mode of the selected image BP to a selection state of a blank page removal candidate or a non-removal candidate, and a data generating unit 88 and a blank page removal level setting unit 78 that operate when the image to be subjected to blank page removal is confirmed by operating the complete button 138 will be described.

[0104] The preview display processing unit 761 displays an image preview on the display unit 22, 102 based on the screen data generated by the above-described screen generation processing. The screen generation processing includes processing for incorporating the image BP of the blank page removal candidate into the screen, processing for incorporating the page information of the image BP into the page information display unit 132, processing for incorporating component data such as the removal level adjustment unit 133, the first selected unit 134, and the second selected unit 135 into the screen, and processing for incorporating an enlarged image ZP of one image of the blank page removal candidate into the enlarged display unit 136.

[0105] The preview display processing unit 761 receives character recognition information from the OCR 86 and blank page determination result information from the blank page determination unit 87, indicating the determination result of whether or not the page is blank. In this embodiment, by default, images of textless documents are not previewed on the blank page preview screen 130. When the "textless document display function" is enabled by selecting the first selection unit 931 (FIG. 4), the preview display processing unit 761 includes in the preview image all images determined to be textless documents based on the character recognition information among the images determined to be blank page removal candidates by the blank page determination unit 87. On the other hand, when the "textless document display function" is disabled, images determined to be textless documents among the images determined to be blank page removal candidates are excluded from the preview image. Furthermore, when the "text-containing document non-display function" is enabled by selecting the second selection unit 932 (FIG. 4), the preview display processing unit 761 excludes from the preview image images determined to be textless documents based on the character recognition information among the images determined to be blank page removal candidates by the blank page determination unit 87. Therefore, when the "textless document display function" is enabled, the image BP of the textless document is also previewed on the blank preview screen 130. Also, when the "text-containing document non-display function" is enabled, the image of the text-containing document is not previewed on the blank preview screen 130.

[0106] In addition, when the preview display processing unit 761 receives an ON / OFF operation signal for a selectable part such as a check box on the screen from the input unit 21, 101 while the blank preview screen 130 is being displayed, the preview display processing unit 761 performs display processing to reflect the input or instruction from the user via the input unit 21, 101 on the screen, such as switching the display mode of the selectable part on the screen between ON and OFF.

[0107] When an image is selected by operating the input units 21, 101, the display switching unit 762 switches the display mode of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected. In this example, when an image is selected by operating the input units 21, 101, the display switching unit 762 switches the display mode of the image to a selected state in which a blank page removal candidate is selected. In this embodiment, two operation methods are provided for placing an image of a blank page removal candidate in a selected state. One method is to select an image BP of a blank page removal candidate by operating a touch panel using the input unit 21 or a pointing device such as a mouse constituting the input unit 101 and place the image in a selected state. When the user selects an image BP from which the blank page is to be removed from among the images BP of the blank page removal candidates by operating the input units 21, 101, the image BP may be highlighted as in the case of the images BP of the third and fourth pages shown in FIG. 12.

[0108] Alternatively, the user may select the image BP that is a candidate for non-removal by operating the input unit 21, 101. For example, a selection section such as a checkbox (not shown) that selects all the image BPs may be provided, and when this selection section is selected and enabled, all the image BPs are highlighted as candidates for blank page removal. When the user then selects an image BP that he or she wants to be a candidate for non-removal, the highlighting is cancelled and the image BP is switched to a candidate for non-removal. As a result, as shown in FIG. 12, the image BPs of the third and fourth pages that the user wants to be the target for blank page removal are highlighted as candidates for blank page removal.

[0109] The other is a method of indirectly selecting images of blank page removal candidates by adjusting the blank page removal level by operating the removal level adjustment unit 133. When the removal level adjustment unit 133 is operated to adjust the blank page removal level, the display of images between blank page removal candidates and non-removal candidates is switched in conjunction with the change in the adjusted value of the blank page removal level. In other words, when the user operates the input units 21, 101 to operate the removal level adjustment unit 133 on the screen and change the blank page removal level, the display switching unit 762 performs switching processing to switch the display between blank page removal candidates and non-removal candidates in conjunction with the changed blank page removal level.

[0110] In conjunction with an operation to decrease the blank page removal level by the removal level adjustment unit 133, an image BP that no longer satisfies the blank page removal level is changed from a blank page removal candidate to a non-removal candidate and displayed. In this example, when the removal level adjustment unit 133 is operated to decrease the blank page removal level and the image BP of the blank page removal candidate is switched to a non-removal candidate, the image BP may disappear from the blank page preview screen 130 and no longer be previewed. In other words, the image BP of the blank page removal candidate may be switched to a non-removal candidate by disappearing from the screen. Also, in conjunction with an operation to increase the blank page removal level by the removal level adjustment unit 133, an image BP that satisfies the blank page removal level is changed from a non-removal candidate to a blank page removal candidate and displayed. In this example, when the removal level adjustment unit 133 is operated to increase the blank page removal level and a non-removal candidate image that was not displayed until then is switched to a blank page removal candidate, the image BP appears on the blank page preview screen 130 and is previewed. That is, when an image of a non-removal candidate appears on the screen, it is switched to a blank page removal candidate.

[0111] In this embodiment, the removal level adjustment unit 133 is, for example, a slider 133A. The user can adjust the blank page removal level by operating the input units 21, 101 to slide the slider 133A.

[0112] When the data generation unit 88 receives a confirmation operation for confirming the blank page removal candidates and the non-removal candidates from the input units 21, 101, the data generation unit 88 generates read data (scanned data) based on the remaining image data after removing the image data of the image data of the document D that are the target of blank page removal, including the blank page removal candidates. The read data is generated as a file in a file format designated by the user, for example. The data generation unit 88 includes the blank page removal processing unit 881 described above as a processing unit that removes the image data of the image data of the document D that are the target of blank page removal, including the blank page removal candidates. The data generation unit 88 also includes the file format conversion unit 882 described above as a processing unit that generates read data based on the remaining image data (non-target of removal) after removing the image data of the target of blank page removal.

[0113] The blank page removal processor 881 performs processing to remove blank pages from the image data of the document D based on the determination result of the blank page determination unit 87 or the determination result of the blank page removal candidate determined by an operation on the blank page preview screen 130. Here, the image data of the document D that is the target of the blank page removal processing is RGB data or YUV data. In other words, the blank page removal processor 881 performs blank page removal processing to remove blank pages, which are image data that have been determined as blank page removal candidates, from the image data of the document D before the file format converter 882 performs processing to convert the file format of the image data of the document D. The blank page removal processor 881 sends the image data after the blank page removal processing to the file format converter 882.

[0114] The file format conversion unit 882 converts the image data of the original D into a file in a specified storage format (file format) among the output conditions specified by the user. The file format conversion unit 882 converts RGB format image data read from the RGB buffer 81 or YUV format image data read from the YUV buffer 83 into a file in the specified storage format. The file format conversion unit 882 generates a file from the image data in the specified storage format, such as JPEG format, PDF format, or TIFF format. If the file is generated within the image reading device 11, the control unit 50 transfers the file to the host device 100 via the output IF 64. On the other hand, if the file is generated within the host device 100, it is stored in a predetermined storage area within the host device 100 specified by the user.

[0115] In this way, when the data generation unit 88 receives a confirmation operation from the input unit 21, 101, it removes the image data of the blank page removal targets, including the images of the blank page removal candidates, from the image data of the document D, and generates scan data based on the remaining image data. This scan data is generated as a file in the specified file format selected by the user in the output conditions. Here, the image data of the blank page removal targets includes image data of the blank page removal targets, which are comprised of documents without text and documents with text that have been excluded from the preview image by the default setting and the function to hide documents with text.

[0116] Furthermore, when the blank page removal level setting unit 78 receives this confirmation operation, it updates the setting to a blank page removal level that satisfies the confirmed blank page removal candidate. Here, the blank page removal level that satisfies the confirmed blank page removal candidate includes the blank page removal level adjusted by operating the removal level adjustment unit 133, and the blank page removal level that is satisfied by the image of the blank page removal candidate after change when the blank page removal candidate is changed by selecting an image BP. In the former case, the blank page removal level setting unit 78 sets the blank page removal level after adjustment adjusted by the removal level adjustment unit 133.

[0117] In the latter case, the blank page removal level setting unit 78 sets a blank page removal level that satisfies the blank page removal candidate that has been confirmed after the blank page removal candidate has been changed by image selection. At this time, the blank page removal level setting unit 78 calculates a blank page removal level that satisfies the image that has been changed to the blank page removal candidate to become a blank page removal candidate. In more detail, the minimum threshold value PS0 that satisfies the fact that the print area pixel count PN, which is the number of pixels in the print area PA, is equal to or less than the threshold value PS0 is calculated based on the histogram HD of the image, and the blank page removal level that corresponds to this minimum threshold value PS0 is determined by referring to the blank page determination table BT.

[0118] At this time, if there are multiple images that are candidates for blank page removal and have been removed, the blank page removal level setting unit 78 updates the setting value of the blank page removal level to match the setting value of the blank page removal level that is the largest among them. In this way, when the selection state is confirmed and the blank page preview screen 130 is completed, the setting value of the blank page removal level is updated. Therefore, when previewing a read image, the preview display processing unit 761 previews the image based on the setting value of the most recent blank page removal level that was set when reading of the document D was completed (when the selection state was confirmed) before the image was previewed.

[0119] Furthermore, the discard button 139 is operated when discarding the scanned image data. If the user checks the image BP on the blank preview screen 130 and wishes to rescan, the user operates the discard button 139 to discard the scanned image data. When the data generation unit 88 receives a discard instruction signal from the input unit 21, 101 indicating that the discard button 139 has been operated, the data generation unit 88 discards the scanned image data.

[0120] 9, when the image processing unit 73 is located within the image reading device 11, the RGB buffer 81, YUV buffer 83, histogram buffer 85, etc. are configured by a volatile memory 61 (FIG. 3) such as a RAM. On the other hand, when the image processing unit 73 is located within the image reading control device 110, the histogram buffer 85, etc. are configured by a memory (not shown) that the computer 120 in the host device 100 has. The YUV generation unit 82 and histogram generation unit 84 that the image reading device 11 has within the image processing unit 73 may be configured by software, or may be configured by hardware for high-speed processing.

[0121] <effect> Next, the operation of the image reading device 11 will be described with reference to FIGS. When scanning a stack of multiple documents D using the image reading device 11, the user selects in advance whether to turn on or off the blank page removal function and preview function on the first setting screen 91. The following will be an example in which the blank page removal function is ON (enabled). Also, it is assumed that the user sets the blank page removal level to, for example, "15" on the first setting screen 91 depending on the background color and paper quality of the documents D. Also, for example, if the desired documents are removed as blank pages, the value of the blank page removal level is lowered. Also, if the blank documents are not removed as blank pages, the value of the blank page removal level is raised.

[0122] When scanning a stack of documents D consisting of multiple sheets, the user places the documents D on the document support 13. Then, the user instructs the start of reading from the menu on the display unit 22 or by operating the input unit 101 of the host device 100. As a result, the control unit 50 receives a reading job. Then, upon receiving the reading job, the computer 60 of the control unit 50 executes a scan processing routine.

[0123] First, the computer 60 reads the original document. That is, the computer 60 drives the transport mechanism 30 to transport the original document D, and drives the light source 41 and the image sensor 42 to read the original document D while it is being transported. The image sensor 42 sends the read data of the original document D to the image processing unit 73 via the AFE 66. The image processing unit 73 generates image data in the YUV format (YUV data) from the image data in the RGB format (RGB data), which is the read data. In this way, the image processing unit 73 temporarily stores the RGB data and YUV data in buffers 81 and 83.

[0124] 13, a blank page preview display control process executed by the computer 60 of the image reading device 11 and the computer 120 of the image reading control device 110 will be described below. Note that the process executed by the computer 60 of the image reading device 11 and the process executed by the computer 120 of the image reading control device 110 are basically the same process, although the input unit and display unit that are the target of input and output are different. Therefore, the blank page preview display control process executed by the computer 120 of the image reading control device 110 will be described below as an example. The process executed by the computer 60 of the image reading device 11 can be understood by replacing the computer 120 with the computer 60, the input unit 101 with the input unit 21, and the display unit 22 with the display unit 102 in the following description.

[0125] When the image reading device 11 finishes scanning, a scan completion notification is sent from the computer 60 of the image reading device 11 to the host device 100. At the end of this scan, the image data obtained by the image reading device 11 reading the document stack D is sent to the host device 100. This image data is used for processing required to generate the blank preview screen 130, such as image preview display and character recognition processing. The image data is, for example, RGB or YUV format image data compressed into a predetermined format, but may also be uncompressed.

[0126] First, in step S11, the computer 120 determines whether scanning has finished. That is, the computer 120 determines whether a scan completion notification has been received from the image reading device 11. If scanning has finished, the computer 120 proceeds to the next step S12, and if scanning has not finished, the computer 120 waits. The time when scanning finishes corresponds to the timing of displaying the preview screen in FIG. 7, which is determined depending on the scan format. When the reading operation of the document stack D is complete and scanning finishes (including the end of the job), the computer 120 proceeds to step S12.

[0127] In step S12, the computer 120 performs a blank page determination process according to the blank page removal level. Specifically, this process is performed by the blank page determination unit 87 of the computer 120. Based on the histogram HD shown in FIG. 10 generated by the histogram generation unit 84, the blank page determination unit 87 offsets the background color luminance value GC, which is the peak luminance value for each color representing the background color of the paper of the document D, by an offset amount ΔOF toward the lower luminance side to determine the luminance threshold value LS. The blank page determination unit 87 calculates the number of pixels in the print area PA, which is the area below the luminance threshold value LS, as the print area pixel number PN. Next, the blank page determination unit 87 obtains the threshold value PS0 corresponding to the current blank page removal level set on the first setting screen 91 shown in FIG. 4 by referencing the blank page determination table BT shown in FIG. 8. Images of the document D for which the print area pixel number PN is below the threshold value PS0 are determined to be blank documents. In this way, the blank page determination process identifies blank document pages from the scan data (read data) containing images of multiple pages of the document D.

[0128] In step S13, computer 120 determines whether or not the setting for displaying a blank document is enabled. If the "Display a blank document" setting is ON, the process proceeds to step S14; if the setting is OFF, the process proceeds to step S15. A user turns this setting ON if they want to check a blank document in a blank preview even if there are no characters on the blank document, or if they want to check whether the blank page removal level value is appropriate in a blank preview. A user with this need turns the "Display a blank document" setting ON because they want to preview images of blank documents that are candidates for blank page removal. If this setting is OFF, a blank preview is not displayed. Therefore, if this setting is ON, it is sufficient to preview the image of a blank document without checking for the absence of text, but if this setting is OFF, it is necessary to use OCR86 to confirm that the document is a blank document that does not require a blank preview.

[0129] In step S14, computer 120 determines whether or not the setting for hiding text-containing documents is enabled. If the "Hide Text-containing Documents" setting is ON, the process proceeds to step S15; if the setting is OFF, the process proceeds to step S16. There is a need to remove blank document images, such as blank pages, of document D, which have only formal text such as page numbers printed in the top or bottom margins. Users who have this need turn the "Hide Text-containing Documents" setting ON. Furthermore, since the presence of text may indicate that the document should not be removed as a blank page, users who wish to check the document with text turn the "Hide Text-containing Documents" setting OFF. If this setting is ON, it is necessary to use OCR86 to confirm that the document contains text and should not be previewed as a blank page.

[0130] In step S15, the computer 120 performs OCR processing. Specifically, the OCR 86 performs character recognition processing on the image of the blank document determined to be blank to determine whether or not text is present. If no text is recognized by the OCR 86, the computer 120 determines the document to be a text-free document, and if text is recognized, the computer 120 determines the document to be a text-containing document.

[0131] In step S16, the computer 120 performs a blank document selection process. That is, the computer 120 selects an image to be previewed from among the blank documents determined to be blank in the blank document determination process. If "Display document without text" is ON, the computer 120 selects a blank document without text. Also, if "Do not display document with text" is ON, the computer 120 does not select a blank document with text.

[0132] In step S17, the computer 120 performs a blank preview screen display process. More specifically, the display control unit 76 of the computer 120 generates an image of a blank preview screen in which, for example, a thumbnail image of the blank document selected in the blank document selection process is arranged in a preview area in the center of the screen, and displays the generated image of the blank preview screen on the display unit 102. As a result, the blank preview screen 130 shown in FIG. 12 is displayed on the display unit 102. Note that in this embodiment, the process of step S17 corresponds to an example of a preview display processing step.

[0133] In step S18, the computer 120 determines whether the blank page removal level has been changed. If the blank page removal level has been changed, the process returns to step S12; if not, the process proceeds to the next step S19. For example, if the user wants to change the value of the blank page removal level, the user changes the value of the blank page removal level by operating the slider 133A. By sliding the slider 133A to the left, the value of the blank page removal level decreases, and by sliding the slider 133A to the right, the value of the blank page removal level increases. The user operates the slider 133A, for example, using a pointing device such as a mouse that constitutes the input unit 101. The computer 120 acquires the change in the blank page removal level and the value of the blank page removal level after the change from the position coordinate values of the slider 133A based on the operation signal input from the input unit 101.

[0134] The user adjusts the blank page removal level by sliding the slider 133A, thereby switching the blank page removal candidate images BP displayed in the preview display area 131 in conjunction with the adjusted blank page removal level. When the blank page removal level is changed in a direction that increases its value, the non-removal candidate images are switched to blank page removal candidates in conjunction with this change. On the other hand, when the blank page removal level is changed in a direction that decreases its value, the non-removal candidate images are switched to blank page removal candidates in conjunction with this change. The user, for example, changes the value of the blank page removal level to a smaller value, and switches the blank page removal candidate images to non-removal candidates in conjunction with this change, thereby selecting the remaining blank page removal candidate images. For example, the user narrows down the number of blank page removal candidate images BP by switching between blank page removal candidates and non-removal candidates. The selection process by switching images is performed by repeatedly executing the processes of steps S12 to S17.

[0135] As shown in Fig. 14, when slider 133A is slid in the direction in which the blank page removal level value increases, threshold value PS0 that determines print area PA in histogram HD increases, so the print area pixel count PN increases a little more, and an image of document D with a slightly higher density is displayed as a blank preview image in preview display area 131. In the example shown in Fig. 14, image BP of a document with a slightly higher density is displayed on the third page. Image BP of a blank document on the third page in Fig. 12 has become page 4 in Fig. 14 because a new blank page removal candidate has been added to page 3.

[0136] For example, if a document with show-through is desired to be blank, and there is a possibility that the show-through document is included in the non-removal candidates, the user slides the slider toward the side where the blank page removal level value increases. Then, as shown in FIG. 14, the third page of the document appears as an image of a blank page removal candidate. In this embodiment, the blank page preview screen that previews a blank page corresponds to an example of a preview screen, and therefore the non-removal candidate is not displayed. In this embodiment, changing from a non-removal candidate to a removal candidate means changing from a hidden state in which the non-removal candidate is not displayed to a displayed state in which the non-removal candidate is displayed as a blank page removal candidate.

[0137] On the other hand, as shown in Figure 15, when slider 133A is slid in the direction that decreases the blank page removal level, threshold value PS0 that determines the print area PA in histogram HD decreases, and an original image whose print area pixel count PN exceeds threshold value PS0, that is, an image that had previously been considered a candidate for blank page removal, is no longer determined to be blank and is lost. In the example of Figure 15, the original images of pages 1 and 2 in Figure 12 have disappeared. In Figure 15, the original pages 3 and 4 are displayed as new pages 1 and 2.

[0138] For example, if there is an image that the user does not want to remove as a blank page, the user slides the slider 133A in the direction that decreases the value of the blank page removal level. Then, as shown in FIG. 15, the images BP of the first and second pages in FIG. 12 disappear. In other words, the original images BP of the first and second pages are no longer determined to be blank pages, and therefore disappear from the preview display area 131. In this embodiment, non-removal candidates are not previewed on the blank page preview screen 130, so when a blank page removal candidate changes to a non-removal candidate, the image of the non-removal candidate disappears from the screen. As the image that has switched from a blank page removal candidate to a non-removal candidate disappears, the displayed image BP is selected as the blank page removal candidate.

[0139] In step S19 in Fig. 13, the computer 120 determines whether or not an image of a document that is a candidate for blank page removal has been selected. On the blank page preview screen 130 shown in Fig. 12, the user selects an image that they wish to remove as a blank page by operating the input unit 101, such as a mouse. If the coordinate values of the operation position based on the operation signal input from the input unit 101 are the position of the image BP of the document that is a candidate for blank page removal, the computer 120 determines that the image has been selected. If the image BP of the document that is a candidate for blank page removal has been selected, the process proceeds to step S20; if not, the process proceeds to step S21.

[0140] In step S20, computer 120 highlights the selected document. Computer 120 identifies the selected image from the coordinate values of the operation position based on the operation signal input from input unit 101, and highlights the selected image by adding a thick frame or a frame of a specific color to the identified image as shown in FIG. 12. In this embodiment, page information corresponding to the selected image among the page information displayed in page information display unit 132 in the left column of blank preview screen 130 shown in FIG. 12 is highlighted with a thick frame or a frame of a specific color. In this embodiment, the processing of step S20 corresponds to an example of a display switching step.

[0141] When the user has finished selecting the blank page removal candidates, he or she operates the Complete button 138 on the blank page preview screen 130. The operation of the Complete button 138 is a confirmation operation that confirms the selected blank page removal candidate images as targets for blank page removal, and also corresponds to a blank page removal operation that instructs the removal of the confirmed blank page removal target images.

[0142] In step S21, the computer 120 determines whether or not a blank page removal operation has been performed. If a blank page removal operation has been performed, the computer 120 proceeds to step S22, and if not, the computer 120 returns to step S18.

[0143] In step S22, the computer 120 sets a blank page removal level. More specifically, this process is executed by the blank page removal level setting unit 78. That is, the blank page removal level setting unit 78 updates the setting to the blank page removal level according to the position of the slider 133A when the selection state is confirmed. Note that in this embodiment, the process of step S22 corresponds to an example of a blank page removal level setting step.

[0144] In step S23, the computer 120 executes blank page removal. That is, the computer 120 removes images determined to be blank page removal targets, i.e., blank pages. More specifically, this process is performed by the blank page removal processing unit 881 in the data generation unit 88. Here, the image reading control device 110 receives image data of the original document D read by the image reading device 11 from the image reading device 11 as image data in a predetermined format, for example, RGB or YUV format image data compressed as necessary. The blank page removal processing unit 881 removes image data of the read original document D that are to be blank page removed, including the selected image PG, from the image data of the read original document D, and sends the remaining image data to the file format conversion unit 882. Note that if the image data is still only stored in the image reading device 11, the computer 120 may notify the image reading device 11 of the images to be removed, and the blank page removal processing unit 881 ( FIG. 9 ) in the image reading device 11 may remove blank pages from the image data.

[0145] In step S24, the computer 120 generates scan data. More specifically, this process is performed by a file format conversion unit 882 in the data generation unit 88. The file format conversion unit 882 generates scan data by converting the image data from the blank page removal processing unit 881 into a file in a predetermined file format specified by the user as an output condition. In this embodiment, the process of step S24 corresponds to an example of a data generation step.

[0146] When the blank page preview screen 130 is displayed on the display unit 22 of the image reading device 11, the computer 60 executes the blank page preview display control process shown in Fig. 13. Which of the computers 60 and 120 executes the blank page preview display control process shown in Fig. 13 may depend on whether the user operates the input unit 21 of the image reading device 11 or the input unit 101 of the host device 100 to start scanning. In other words, if the user operates the input unit 21 of the image reading device 11 to instruct the start of scanning, the computer 60 that receives the instruction to start scanning may execute the blank page preview screen display control process. On the other hand, if the user operates the input unit 101 of the host device 100 to instruct the start of scanning, the computer 120 that receives the instruction to start scanning may execute the blank page preview screen display control process.

[0147] In addition, when the computer 60 of the image reading device 11 executes the blank preview screen display control process, the file format conversion unit 882 in the image reading device 11 transmits the file converted into the file format specified in the output conditions to the host device 100 via the output IF 64.

[0148] As described above in detail, according to this embodiment, the following effects can be obtained. (1) The image reading system 10 includes an image reading device 11 that reads an original D and an image reading control device that controls the image reading device 11. The image reading system 10 has a blank page removal function that removes, as blank pages, images of the original D read by the image reading device 11 that are blank page removal candidates and that satisfy a blank page removal level. The image reading system 10 includes a preview display processing unit 761 that displays a selectable preview of at least some of the images of the read original D on the display unit 22, 102, a display switching unit 762 that, when an image is selected by operating the input unit 21, 101, switches the display state of the image to a selected state in which the blank page removal candidate is selected, a data generation unit 88, and a blank page removal level setting unit 78. When the selection state is confirmed by operating the input unit 21, 101, the data generation unit 88 generates read data based on the remaining image data from the image data of the original D after removing the image data to be subjected to blank page removal, including the confirmed blank page removal candidate. The blank page removal level setting unit 78 sets a blank page removal level at which the image in the confirmed selected state can be a candidate for blank page removal.

[0149] Therefore, when a user checks the previewed image and selects an image by operating the input unit 21, 101, the display mode of the image switches to a selection state in which a blank page removal candidate or a non-removal candidate is selected. Also, a blank page removal level suitable for the selection state of the image from which blank pages are to be removed can be set. Therefore, the user can appropriately select the image from which blank pages are to be removed and set the blank page removal level with a simple operation.

[0150] (2) A blank page determination unit 87 is provided that determines, based on the image data of the read document D, images that satisfy the blank page removal level as blank page removal candidates and images that do not satisfy the blank page removal level as non-removal candidates. The preview display processing unit 761 displays a preview of at least a portion of the images of the document D that have been determined to be blank page removal candidates on the display units 22 and 102. Therefore, since at least a portion of the images that have been determined to be blank page removal candidates are displayed in preview, the user can simply select the images that they wish to remove from the images that are blank page removal candidates. This makes it easy for the user to select the images of the blank document that they wish to remove.

[0151] (3) The preview display processing unit 761 displays the removal level adjustment unit 133, which allows the adjustment of the blank page removal level, on the display unit 22, 102. When the removal level adjustment unit 133 adjusts the blank page removal level through operation of the input unit 21, 101, the display switching unit 762 switches the image display mode to a selection state in which a blank page removal candidate is selected in conjunction with the changed blank page removal level. Therefore, the blank page removal level can be adjusted by the removal level adjustment unit 133, and the image display mode switches to a selection state in which a blank page removal candidate is selected in conjunction with the adjusted blank page removal level. Therefore, while adjusting the blank page removal level with the removal level adjustment unit 133, the user can check the image display mode that switches in conjunction with the adjusted blank page removal level, thereby appropriately selecting the image that the user desires and adjusting the blank page removal level to the desired blank page removal level.

[0152] (4) The removal level adjustment unit 133 is a slider 133A that is slid to a position corresponding to the value of the blank page removal level. Therefore, when the user slides the slider 133A, the blank page removal level is adjusted to a value corresponding to the slide position, and the blank page removal candidate switches to a selected state in conjunction with the adjusted blank page removal level. Therefore, the user can easily adjust to the desired blank page removal level. Furthermore, because it is a slide operation, it is easier to visually confirm which overall level it is at and how much adjustment is required compared to inputting a numerical value, so it is possible to easily adjust to an appropriate blank page removal level.

[0153] (5) Images that no longer satisfy the blank page removal level are displayed as candidates for removal in conjunction with an operation to reduce the blank page removal level by the removal level adjustment unit 133. Therefore, while performing an operation to reduce the blank page removal level by the removal level adjustment unit 133, it is possible to see the display mode of images that change from blank page removal candidates to non-removal candidates in conjunction with the value of the blank page removal level that is adjusted downward. Therefore, it is possible to appropriately adjust the blank page removal level and select images to be removed as blank pages.

[0154] (6) The preview display processing unit 761 displays both the previewed image and the removal level adjustment unit 133 in a visible state on the display unit 22, 102. Therefore, when the user operates the removal level adjustment unit 133, the user can appropriately adjust the blank page removal level while checking changes in the image display.

[0155] (7) When a scanned image is previewed, the preview display processing unit 761 previews the image based on the most recent blank page removal level that was set when scanning of the document before the image was previewed. Therefore, since the image is previewed based on the most recent blank page removal level that was set when scanning of the document before the preview was completed, an appropriate blank page removal level is more likely to be applied than when the user sets the blank page removal level again before starting scanning of the current document. Therefore, it is easier to reduce the number of operations the user performs to select images as blank page removal candidates.

[0156] (8) The preview display processing unit 761 displays the page information display unit 132, which displays page information of the previewed image, on the display unit 22, 102. When an image is selected from the previewed images by operating the input unit 21, 101, the display switching unit 762 highlights the page information corresponding to the image. Therefore, it is possible to confirm from the page information in the page information display unit whether or not an image has been selected as a blank page removal candidate. Even if an image has been mistakenly selected as a blank page removal candidate, it is easy to discover this.

[0157] (9) The preview display processing unit 761 displays an enlarged image ZP of an image selected by operating the input unit on the display unit 22, 102. Therefore, the user can check the image selected by the input unit 21, 101 in the enlarged image, and can appropriately determine whether the image is necessary or not, such as whether to discard it as a blank document.

[0158] (10) The first selection unit 134, 931 may be displayed on the display unit 22, 102, allowing the user to select whether or not to include textless document images as blank page removal candidate images to be displayed by the preview display processing unit 761. Therefore, since it is possible to select to preview textless document images, the user can appropriately determine whether or not textless document images should also be removed as blank documents by looking at the images. This reduces the number of cases where necessary textless document images are removed as blank pages against the user's wishes. It also meets the needs of users who do not need to check textless document images.

[0159] (11) The second selection area 135, 932 is displayed on the display unit 22, 102, allowing the user to select whether or not to include text-containing document images in the blank page removal candidate images displayed by the preview display processing unit 761. This allows the user to select whether or not to display text-containing document images among images determined as blank page removal candidates, depending on the user's needs. For example, this eliminates the need to check blank documents containing only page information text. Furthermore, it also meets the user's needs to check text-containing document images even if the images are determined as blank page removal candidates.

[0160] (12) When the continuous feed mode is executed in which the original documents D for one job are set in multiple batches and continuously read as one job, the preview display processing unit 761 displays at least a portion of the image on the display unit 22, 102 when reading of the original documents D set once is completed. The blank page removal level setting unit 78 is configured to be able to change the blank page removal level according to the image selected even during the job. Therefore, when the continuous feed mode is executed, at least a portion of the image is displayed as a preview even during the job, and the blank page removal level can be changed according to the image selected even during the job. The image read from the next document set during the job can be displayed as a preview based on the changed blank page removal level.

[0161] (13) The image reading control device, which controls the image reading device 11 that reads the original D, has a blank page removal function that removes, as blank pages, images of the original D read by the image reading device 11 that satisfy a blank page removal level. The image reading control device includes a preview display processing unit 761 that displays, on the display unit 22, 102, a selectable preview of at least some of the images of the original D read by the image reading device 11; a display switching unit 762 that switches the display mode of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected when an image is selected by operating the input unit 21, 101; a data generation unit 88; and a blank page removal level setting unit 78. When the selection state is confirmed by operating the input unit 21, 101, the data generation unit 88 generates read data based on the remaining image data from the image data of the original D after removing image data that is subject to blank page removal, including the confirmed blank page removal candidate. The blank page removal level setting unit 78 sets a blank page removal level that allows the confirmed selected image to be a blank page removal candidate. This configuration achieves the same effects as the image reading system 10.

[0162] (14) The image reading device 11 has a blank page removal function that removes, as blank pages, images that satisfy a blank page removal level from among images read from the original D. The image reading device 11 includes a preview display processing unit 761 that displays a selectable preview of at least some of the images from the read original D on the display unit 22, 102, a display switching unit 762 that switches the display state of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected when an image is selected by operating the input unit 21, 101, a data generation unit 88, and a blank page removal level setting unit 78. When the selection state is confirmed by operating the input unit 21, 101, the data generation unit 88 generates read data based on the remaining image data from the image data of the original D after removing image data that is subject to blank page removal, including the confirmed blank page removal candidate. The blank page removal level setting unit 78 sets a blank page removal level that allows the confirmed selected image to be a blank page removal candidate. This configuration achieves the same effects as the image reading system 10.

[0163] (15) The image reading method performs a blank page removal process in which, from among images read by the image reading device 11 on the original D, images that satisfy a blank page removal level are removed as blank pages. This image reading method includes: previewing at least some of the images of the read original D on the display unit 22, 102 in a selectable state; when an image is selected by operating the input unit 21, 101, switching the display state of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; when the selection state is confirmed by operating the input unit 21, 101, generating read data based on the remaining image data from the image data of the original D after removing image data that is subject to blank page removal, including the confirmed blank page removal candidate; and setting a blank page removal level that can treat the confirmed selected image as a blank page removal candidate. This method achieves the same effects as the image reading system 10.

[0164] (16) The program PR is executed by the computer 60, 120, which realizes a blank page removal function that removes blank pages that satisfy a blank page removal level from images of the original D read by the image reading device 11. The program PR causes the computer 60, 120 to execute a preview display processing step (S17), a display switching step (S16), a data generation step (S23, S24), and a blank page removal level setting step (S22). The preview display processing step displays a selectable preview of at least some of the images of the original D read by the image reading device 11 on the display unit 22, 102. The display switching step, when an image is selected by operating the input unit 21, 101, switches the display state of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected. The data generation step, when the selection state is confirmed by operating the input unit 21, 101, generates read data based on the remaining image data from the image data of the original D after removing the image data to be subjected to blank page removal, including the confirmed blank page removal candidate. The blank page removal level setting step sets a blank page removal level at which the confirmed selected image can be a blank page removal candidate. By having the computer 60, 120 execute this program PR, the same effect as that of the image reading system 10 described above in (1) can be obtained.

[0165] (Second embodiment) Next, a second embodiment will be described with reference to Figs. 16 to 20. In this second embodiment, the configuration and method apply the function of switching the display of a previewed image between blank page removal candidates and non-removal candidates, and the function of updating the blank page removal level, to the document preview screen 140, rather than the blank page preview screen 130. The configuration of the image reading system 10 is the same as that of the first embodiment, except that the computers 60, 120 execute the program PR to process the document preview screen 140. Below, only the processing related to the control of the document preview screen 140 by the computers 60, 120 and each component configured by their software will be described.

[0166] 3, the control unit 50 of the image reading device 11 and the image reading control device 110 include a display control unit 76, a blank page removal setting unit 77, a blank page removal level setting unit 78, a preview setting unit 79, an OCR 86, a blank page determination unit 87 as an example of a determination unit, and a data generation unit 88. The display control unit 76 includes a preview display processing unit 761 and a display switching unit 762. The data generation unit 88 includes a blank page removal processing unit 881 and a file format conversion unit 882.

[0167] The preview display processing unit 761 displays a selectable preview of at least some of the images of the read original document D on the display unit 22, 102. In this embodiment, the preview display processing unit 761 displays a selectable preview of at least images including the non-removal candidate images on the display unit 22, 102. In particular, the preview display processing unit 761 displays a preview of all of the images of the original document D read in one job on the original preview screen 140 without acquiring blank page determination result information from the blank page determination unit 87. For this reason, the blank page determination result from the blank page determination unit 87 is not required, so the blank page determination unit 87 may not be required. Note that the preview display processing unit 761 may also display a preview of non-removal candidate images excluding blank page removal candidate images determined to be blank based on the blank page determination result information from the blank page determination unit 87 among the images of the original document D.

[0168] When an image is selected by operating the input units 21, 101, the display switching unit 762 switches the display mode of the image to a selection state in which a blank page removal candidate or a non-removal candidate is selected. In this example, when an image is selected by operating the input units 21, 101, the display switching unit 762 switches the display mode of the image to a selection state in which a non-removal candidate is selected.

[0169] When the data generation unit 88 receives a confirmation operation to confirm a blank page removal candidate from the input unit 21, 101, it generates read data (scanned data) based on the remaining image data obtained by removing the image data to be subjected to blank page removal, including the blank page removal candidate, from the image data of the document D. Note that the confirmation operation to confirm a blank page removal candidate does not have to be performed when a blank page removal candidate is selected, and may be performed when a non-removal candidate is selected. In this case, confirmation of the non-removal candidate also confirms the opposite blank page removal candidate. Such indirect confirmation of a blank page removal candidate is also included in confirmation of a blank page removal candidate.

[0170] The blank page removal level setting unit 78 sets a removal level that satisfies the confirmed blank page removal candidate. The blank page removal level setting unit 78 calculates a blank page removal level that satisfies the requirement that an image be a blank page removal candidate. In more detail, the unit calculates a minimum threshold value PS0 that satisfies the requirement that the print area pixel count PN, which is the number of pixels in the print area PA, is equal to or less than the threshold value PS0 based on the histogram HD of the image, and then determines the blank page removal level that corresponds to this calculated threshold value PS0 by referring to the blank page determination table BT.

[0171] <Preview screen> FIG. 16 illustrates an original preview screen 140 displayed on the display unit 22, 102 after a job is completed when the preview function is enabled in this embodiment. The original preview screen 140 shown in FIG. 16 displays a preview of all scanned images on the display unit 22, 102. The original preview screen 140 also serves as a setting screen that allows an operation to set images PG to be removed as blank pages as blank page removal candidates. Although the present embodiment is configured to display a preview at the end of a job, similar to the blank page preview screen 130 in the first embodiment, in a continuous feed mode in which a single job's worth of originals D can be loaded and scanned multiple times on the original support 13, the original preview screen 140 may be displayed even during a job when scanning of a single set of originals D is completed. In this case, in the continuous feed mode, the blank page removal level may be changeable even during a job when scanning of a single set of originals D is completed. For example, the blank page removal level may be changeable on the preview screen 140.

[0172] 16, the document preview screen 140 includes a preview display area 141 that displays a preview of all scanned images PG, and a page information display area 142 that displays page information related to the previewed images PG. The document preview screen 140 includes a display image number selection function that allows the user to select the number of images to be displayed in the preview display area 141, and a page turning function that turns the pages forward and backward in the preview display area 141. Since there is a limit to the number of images PG that can be displayed in the preview display area 141, displaying all of the images PG may take multiple pages.

[0173] The document preview screen 140 may also include a removal level adjustment unit 143 that can adjust the blank page removal level. The removal level adjustment unit 143 may also include a slider 143A as an operation unit that can be operated on the screen by inputting data from the input units 21 and 101. That is, the removal level adjustment unit 143 may include a slider 143A that is slid to a position corresponding to the value of the blank page removal level. The slider 143A shown in FIG. 16 basically has the same function as the slider 133A (FIG. 12) of the first embodiment.

[0174] The preview display processing unit 761 displays the preview screen 140 shown in FIG. 16 on the display unit 22, 102 in a state where both the image PG and the removal level adjustment unit 143 are arranged so as to be visible.

[0175] The removal level adjustment unit 133 may also have a function for adjusting the blank page removal level via operation of the input units 21 and 101, thereby switching the display mode of the image PG to a selected state in which the blank page removal candidate is selected in accordance with the adjusted blank page removal level. When an image PG is selected via a touch operation on the input unit 21 or a pointing device such as a mouse constituting the input unit 101, the selected image PG is highlighted. In the example shown in FIG. 16 , the image PG is highlighted by a highlighting unit 145, such as a highlighting frame, that surrounds the selected images PG of pages 3 and 4. When the user selects an image PG, the image PG is switched to a blank page removal candidate and highlighted by a first highlighting unit 145, such as a display frame, and the page information corresponding to the image PG in the page information display unit 132 is highlighted by a second highlighting unit 142A, such as a display frame, that surrounds it. This allows the user to quickly identify the image PG selected as a blank page removal candidate by highlighting the image PG and the page information for that image.

[0176] 16, the highlighting is performed by displaying a thick frame (image frame) surrounding the image PG and a thick frame (display area frame) surrounding the display area of each image. The highlighting may also be performed by a mark superimposed on the image.

[0177] The document preview screen 140 is provided with a selection section 144 such as a check box for setting whether the removal level update function is enabled or disabled. The removal level adjustment section 143 may be configured such that, when an image PG is selected as a blank page removal candidate, a slider 143A moves in conjunction with the selection and the indicated value changes.

[0178] Furthermore, when an image PG selected on the document preview screen 140 is confirmed as a blank page removal target and then removed, a removal level update function is provided that updates the removed image PG to a blank page removal level that satisfies the requirement that the image PG be a blank page removal candidate. The document preview screen 140 is provided with a selection section 144 that allows a selection to enable (ON) the removal level update function. The selection section 144 is, for example, a check box, but may also be a display component that allows selection of one of two or more options, such as a radio button, a pull-down selection section, or a push button.

[0179] The document preview screen 140 also includes a blank page removal button 146, a complete button 147, and a discard button 148. When the blank page removal button 146 is operated by operating the input units 21, 101 and the selected blank page removal candidate is confirmed, the display switching unit 762 switches the display to remove the image PG of the selected blank page removal candidate from the preview display area 141. The fact that the image PG that has disappeared from the preview display area 141 is a blank page removal candidate is saved by information such as a flag. Note that the image data of the image PG that has disappeared from the preview display area 141 is not yet discarded, but may be discarded.

[0180] The user can also confirm the image of the selected blank page removal candidate as the image to be removed without using the blank page removal button 146 by operating the complete button 147 while a blank page removal candidate is selected. When the user operates the complete button 147 by operating the input unit 21, 101 and the selected blank page removal candidate is confirmed, the data generation unit 88 removes the image data of the blank page removal target, including the image PG of the blank page removal candidate, from the image data of the document D, and generates scan data (read data) based on the remaining image data. Alternatively, when the user operates the complete button 147 by operating the input unit 21, 101 and the selected non-removal candidate is confirmed, the data generation unit 88 removes the image data of the blank page removal target other than the image PG of the selected non-removal candidate from the image data of the document D, and generates scan data (read data) based on the image data of the non-removal candidate.

[0181] Furthermore, there are cases where the blank page removal button 146 is operated to delete the images of the blank page removal candidates from the preview display area 141 before operating the complete button 147. In this case, when the complete button 147 is operated, the images of the blank page removal candidates that have already disappeared from the screen and the images of the blank page removal candidates that are displayed in a selected state as the blank page removal candidates are confirmed as the images to be removed. The data generation unit 88 removes the image data confirmed as the images to be removed from the image data of the original D, and generates scan data (read data) based on the remaining image data. Note that the discard button 148 is operated when it is desired to discard the image data of the read original D, as in the first embodiment.

[0182] FIG. 17 shows a third management table SD3 for managing the display timing of the preview screen 140 for each scan format and the reflection timing of the setting value of the blank page removal level changed on the preview screen 140.

[0183] Based on the scan format selected on the second setting screen 92, the computer 60, 120 refers to the third management table SD3 to obtain the timing for displaying the preview screen 140 and the timing for reflecting the setting value of the blank page removal level.

[0184] 17, the preview screen 140 is displayed "after the job ends" for both normal scanning and AFM & continuation jobs. The setting value of the blank page removal level is reflected "from the next job" for both normal scanning and AFM & continuation jobs. Note that for both AFM and continuation jobs, the preview screen 140 is displayed "after the job ends" and the setting value of the blank page removal level is reflected "from the next job."

[0185] After scanning starts, the computer 120 executes the preview screen display process shown in Fig. 19. Note that, although the following description will be given taking as an example a case where the computer 120 on the image reading control device 110 side executes the program PR for the preview screen display process, the process is basically the same when the computer 60 in the image reading device 11 executes the program PR for the preview screen display process.

[0186] First, in step S31, computer 120 determines whether scanning has finished. If scanning has finished, the process proceeds to step S32; if scanning has not finished, the process remains on standby. Note that step S31 is a process for determining whether the timing for displaying preview screen 140 has arrived. The time at which scanning has finished being determined here is the time after the job ends, as shown in FIG. 17, when all of the original documents D for one job have been read.

[0187] In step S32, the computer 120 displays the preview screen 140. More specifically, this process is executed by the preview display processing unit 761. The preview display processing unit 761 performs a screen generation process to incorporate images of all scanned documents D and page information of each image onto the screen, thereby generating screen data, and displays the preview screen 140 shown in FIG. 16 on the display unit 102 based on the generated screen data. More specifically, the preview display processing unit 761 performs a preview display process to display this preview screen 140 on the display unit 102. Note that in this embodiment, the process of step S32 corresponds to an example of a preview display processing step.

[0188] In step S33, computer 120 determines whether a document to be subject to blank page removal has been selected. If a document to be subject to blank page removal has been selected, the process proceeds to step S34; if a document to be subject to blank page removal has not been selected, the process proceeds to step S35. The user checks the image PG displayed in preview display area 141 of preview screen 140, and if there is an image that the user wants to remove as a blank page, selects that image PG by operating input unit 101. For example, if document D is determined to not be a blank document due to wrinkles or the color of paper fibers such as recycled paper and is displayed on the preview screen, the user wants to remove it as a blank page, so selects the image of document D as the image to be subject to blank page removal.

[0189] In step S34, the computer 120 highlights the selected document. More specifically, this process is executed by the display switching unit 762. For example, the image PG is highlighted, as in the case of the images PG of the third and fourth pages on the preview screen 140 shown in FIG. 16. That is, when an image PG is selected by operating the input unit 101, the computer 120 switches the display state of the image PG to a selected state in which a blank page removal candidate has been selected. Because the selected image PG is highlighted, the user can visually confirm that the selected image PG is in a selected state in which it has been selected as a blank page removal candidate. In this embodiment, the processes of steps S33 and S34 correspond to an example of a display switching step.

[0190] In step S35, the computer 120 determines whether or not a blank page removal operation has been performed. When the user has finished selecting images PG from which blank pages are to be removed, the user performs a blank page removal operation by operating the blank page removal button 146 through the input unit 101. This blank page removal operation corresponds to a confirmation operation that confirms the selection state. If a blank page removal operation has been performed, the process proceeds to step S36; if not, the process returns to step S33. If the user has not performed a blank page removal operation, the processes of steps S33 to S35 are repeated, and each time the user selects an image PG (positive determination in step S33), that image PG is highlighted (step S34). In this way, when the user has finished selecting images, the user operates the blank page removal button 146 using the input unit 101. At this time, it is determined in step S35 that a blank page removal operation has been performed, so the computer 120 proceeds to step S36.

[0191] In step S36, the computer 120 executes blank page removal. More specifically, the computer 120 deletes the image PG that is in a selected state as a candidate for blank page removal from the preview display area 141. As a result, the image PG selected as a target for blank page removal disappears from the preview display area 141.

[0192] In step S37, the computer 120 determines whether the blank page removal level update is enabled. If the selection section 144 of the blank page removal level update function is selected and the blank page removal level update function is enabled (ON), the process proceeds to step S38. On the other hand, if the selection section 144 is not selected and the blank page removal level update function is disabled (OFF), the process proceeds to step S42. If the blank page removal level update is enabled, a confirmation screen 150 shown in FIG. 18 is displayed. For example, the confirmation screen 150 is displayed so as to be superimposed on the preview screen 140. If the user wants to keep the blank page removal level update function enabled, the user selects a "Yes" button 151 by operating the input unit 101. If the user does not want to update the blank page removal level, the user selects a "No" button 152 on the confirmation screen 150.

[0193] In step S38, the computer 120 determines whether or not there has been a change in the blank page removal level. If there has been a change in the blank page removal level, the process proceeds to step S39; if there has been no change in the blank page removal level, the process proceeds to step S42. Here, the blank page determination unit 87 may perform blank page determination based on the blank page removal level that was set before the preview screen 140 was displayed, based on the image data of the scanned document D. If there are images that are blank page removal candidates among the images of the document D, and all of the images PG that are in a selected state selected by the user are images that are blank page removal candidates, the blank page removal level is determined to have not been changed. Furthermore, if the images PG that are in a selected state selected by the user include at least one image other than the blank page removal candidates, the blank page removal level is determined to have been changed. Note that it may also be determined that there has been a change in the blank page removal level simply if there is at least one image that is in a selected state as a blank page removal candidate.

[0194] In step S39, the computer 120 determines whether there are multiple images. That is, the computer 120 determines whether there are multiple images for which the blank page removal level has been changed. If there are not multiple images, the computer 120 proceeds to step S40, and if there are multiple images, the computer 120 proceeds to step S41.

[0195] In step S40, the computer 120 reflects the blank page removal level. That is, the setting of the blank page removal level for one image whose blank page removal level has been changed is updated to a blank page removal level that allows the blank page determination unit 87 to determine it as a blank page. In detail, this process is executed by the blank page removal level setting unit 78. The blank page removal level setting unit 78 acquires a histogram HD based on the image data of the selected image PG, and determines the blank page removal level corresponding to the smallest threshold value PS0 among the threshold values PS0 that are equal to or greater than the value of the print area pixel count PN in the histogram HD. If necessary, it may be confirmed that the determined blank page removal level is greater than the currently set blank page removal level. The blank page removal level setting unit 78 then sets the determined blank page removal level.

[0196] In step S41, the computer 120 sets the blank page removal level to the highest value. That is, among the multiple images for which the blank page removal level has been changed, the blank page removal level setting is updated to the highest value among the multiple blank page removal levels at which the blank page determination unit 87 can determine each image as a blank page. In detail, this process is executed by the blank page removal level setting unit 78. The blank page removal level setting unit 78 acquires a histogram HD based on the image data of the selected image PG, and determines the blank page removal level corresponding to the smallest threshold value PS0 among the threshold values PS0 that are equal to or greater than the number of print area pixels PN in the histogram HD. If necessary, it may be confirmed that the determined blank page removal level is greater than the currently set blank page removal level. Then, the blank page removal level setting unit 78 sets the blank page removal level to the highest value among the multiple determined blank page removal levels. Note that in this embodiment, the processes of steps S39 to S41 correspond to an example of a blank page removal level setting step.

[0197] In step S42, the computer 120 generates scan data. This process is performed by the data generation unit 88. The data generation unit 88 generates scan data based on the remaining image data obtained by removing image data of blank page removal candidates, including the selected image PG, from the image data of the read document D. More specifically, the blank page removal processing unit 881 removes image data of blank page removal candidates, including the selected image PG, from the image data of the read document D, and sends the remaining image data to the file format conversion unit 882. The file format conversion unit 882 generates scan data by converting the image data from the blank page removal processing unit 881 into a file in a predetermined file format set by the user as an output condition. In this embodiment, the process of step S42 corresponds to an example of a data generation step.

[0198] According to the second embodiment, in addition to the effects (1), (3) to (8), and (13) to (16) of the first embodiment, the following effects are also obtained. (17) The preview display processing unit 761 displays images including at least non-removal candidate images in a selectable state on the display units 22, 102. When an image is selected by operating the input units 21, 101, the display switching unit 762 switches the display state of the image to a selected state in which the blank page removal candidate is selected.

[0199] Therefore, the user can remove the image as a candidate for blank page removal by selecting the image that the user wants to set as a candidate for blank page removal from among the images that include at least the non-candidate image displayed on the display unit 22, 102 by operating the input unit 21, 101. In addition, the display mode of the image changes, allowing the user to confirm on the screen of the display unit 22, 102 that the selected image has become the image for blank page removal.

[0200] (18) When at least some of the images displayed by the preview display processing unit 761 include images that are non-removal candidates and there are multiple images that have been changed from non-removal candidates to blank page removal candidates, the blank page removal level setting unit 78 may set the largest blank page removal level among multiple blank page removal levels that can make each of the multiple images a blank page removal candidate.

[0201] According to this configuration, even if a previewed non-removal candidate is changed to a blank page removal candidate and there are a plurality of changed images, an appropriate blank page removal level can be set. (Third embodiment) The third embodiment will be described with reference to FIGS. 20 and 21. The only difference is the processing performed by the computers 60 and 120. The configurations of the image reading device 11, the image reading control device 110, and the blank page preview screen 130 are essentially the same. Therefore, the same components are denoted by the same reference numerals and will not be described again. In the first embodiment, sliding the slider 133A of the removal level adjustment unit 133 caused the non-removal candidate image BP to disappear or the blank page removal candidate image BP to appear. However, this is not limited to this. In this embodiment, an image that has switched from a blank page removal candidate to a non-removal candidate is marked to indicate that it is no longer a blank page removal candidate. The highlighting is not limited to a display frame or the like, and may be a mark. The non-volatile memory 62 of the image reading device 11 and the storage unit of the host device 100 store the program PR shown in FIG. 13. This program PR includes the blank page preview screen display processing routine shown in FIG. 20, which is the processing in step S17.

[0202] The following describes the blank preview screen display process executed by the computer 120 on the image reading control device 110 side. Note that even when executed by the computer 60 in the image reading device 11, the processing content is basically the same, although the input unit 21 and the display unit 22 are different. The processing shown in FIG. 13 is the same as that in the first embodiment.

[0203] After the scan is completed, the blank page preview screen 130 is displayed on the display unit 102 (step S17). Thereafter, the user operates the input unit 101 on the blank page preview screen 130 to change the blank page removal level by operating the removal level adjustment unit 133 (step S18) or to select an image BP (FIG. 19). If the blank page removal level has been changed (positive determination in step S18), the process returns to step S12, and the processes of steps S12 to S17 are executed. At this time, in step S17, the blank page preview screen 130 is displayed again.

[0204] In step S17 of FIG. 13, the computer 120 executes a blank preview screen display process shown in FIG. First, in step S51, the computer 120 determines whether or not a re-display is required. If a re-display is not required, the process proceeds to step S54, where the blank preview screen 130 is displayed. This process is the same as in the first embodiment. On the other hand, if a re-display is required, the process proceeds to step S52.

[0205] In step S52, computer 120 determines whether the number of blank pages has decreased. If the number of blank pages has decreased, the process proceeds to step S53; if the number of blank pages has not decreased, the process proceeds to step S54. For example, as shown in FIG. 21, when removal level adjustment unit 133 is operated to decrease the removal level value, the number of blank pages (candidates for blank page removal) determined to be blank documents by blank page determination unit 87 may decrease. In this case, the process proceeds to step S53.

[0206] In step S53, the computer 120 marks the documents that are no longer blank. For example, when the removal level adjustment unit 133 is operated to adjust the blank page removal level, the display switching unit 762, which has received input for that operation, switches the image display mode between blank page removal candidates and non-removal candidates in conjunction with that operation so as to satisfy the adjusted blank page removal level. The display switching unit 762 then marks the images BP of the first and second pages that have been switched from blank page removal candidates to non-removal candidates with marks 155 indicating that they are non-removal candidates, in a position superimposed on the images BP. In other words, the display switching unit 762 generates screen data in which marks 155 have been added to the images that have been switched from blank page removal candidates to non-removal candidates.

[0207] In step S54, the computer 120 displays a blank page preview screen. That is, the preview display processing unit 761 displays the blank page preview screen 130 based on the screen data. As a result, as shown in FIG. 21, the images BP of the first and second pages that have been switched from blank page removal candidates to non-removal candidates are given a mark 155 that is superimposed on the image BP as a display mode that indicates that the image has been switched to a non-removal candidate. Note that the image highlighting may be a display frame instead of the mark 155. Furthermore, when the user selects an image BP that is a blank page removal candidate (positive determination in step S19), in the next step S20, the display frame may be replaced with a highlighting that adds the mark 155 to the image BP.

[0208] The above embodiment can be modified as shown in the following modified examples. Furthermore, the above embodiment and the modified examples shown below can be appropriately combined to form further modified examples, or the modified examples shown below can be appropriately combined to form further modified examples.

[0209] The image reading device 11 or the host device 100 may analyze information acquired via a network such as the Internet and provide the user with recommended information. That is, a server that analyzes information analyzes information acquired via the network from the host device 100, etc., with the user's permission, and generates recommended reading condition information based on the user's usage situation in using the image reading device 11 as recommended information. The server may provide recommended information based on each user's usage situation to the host device 100 of each user on the network via the network and display the information on the display unit 102. The recommended information may include blank page removal level information. For example, a host device 100 of a user who frequently scans text documents may be recommended an appropriate blank page removal level value based on that usage situation. A host device 100 of a user who frequently scans documents with page numbers printed on it may be recommended an appropriate blank page removal level setting based on that usage situation. A host device 100 of a user who frequently scans documents without text, such as documents containing only images, may be recommended an appropriate blank page removal level value based on that usage situation. For a host device 100 of a user who frequently scans recycled paper documents, an appropriate setting value for the blank page removal level may be recommended according to the usage situation.

[0210] The host device 100 may include a registration information management unit configured by software that manages registration condition information registered by the user as favorite information. The registration condition information includes image correction information such as sharpness and brightness correction values, blank page removal level information, OCR language information, and file generation format information such as JPEG and PDF. The image reading device 11 may read the registration condition information registered by the user as favorite information from the registration information management unit of the host device 100 and display it on the display unit 22, 102. Furthermore, when the image reading device 11 accepts a job, it may read the registration condition information registered by the user as favorite information from the registration information management unit of the host device 100 and perform the scanning operation of the document D. Furthermore, the registration information management unit may be part of the image reading control device 110 configured by a driver program, or it may be separate from the image reading control device 110. For example, at the end of scanning by a reading operation based on the registered condition information, the removal level adjustment unit 133 on the blank page preview screen 130 is displayed pointing to a value based on the blank page removal level information in the registered condition information as the current blank page removal level. For example, on the blank page preview screen 130 in Fig. 12, the blank page removal level value "15" indicated by the slider 133A is displayed based on the blank page removal level information in the registered condition information. Also, a registration information setting unit for setting whether to register as favorite information may be added to the blank page preview screen 130, and when the registration information setting unit is enabled, the value of the blank page removal level updated on the blank page preview screen 130 may be updated as blank page removal level information managed by the registration information management unit.

[0211] The removal level adjustment unit 133 is not limited to the slider 133A. It may be a button row with multiple buttons for each removal level. It may also be a display frame in which the level value is displayed, and a + button and a - button. It may also be a display meter instead of a display frame. The display meter may be a display having multiple square blocks arranged in a row, or a bar-shaped display area. The display meter visually indicates the removal level value by the number of blocks whose color changes, or the area of the color. The operation unit is not limited to the slider 133A, and may also be a page number button for selecting an image. This button is operated by the input unit 21, 101.

[0212] The removal level adjustment unit 133 may be displayed superimposed on the preview screen. For example, when the blank page preview screen 130 is displayed at the end of scanning, the removal level adjustment unit 133 is not displayed, and only the enlarged image ZP is displayed on the screen. When an operation to enable the blank page removal level adjustment function is performed, the removal level adjustment unit 133 is displayed. In this case, the removal level adjustment unit 133 may be displayed in a position that does not overlap the preview display area 131 and the enlarged image ZP, as shown in FIG. 12 , or may be displayed superimposed on a position that overlaps the preview display area 131.

[0213] In the first embodiment, the image of the removal candidate disappeared, but the image of the removal candidate may be highlighted. For example, the frame of the image of the removal candidate may be highlighted with a thick or colored line, or text, a mark, or a symbol indicating that the image is a removal candidate may be superimposed on the image of the removal candidate.

[0214] In the second embodiment, the image of the removal candidate selected by operation is highlighted, but the image of the removal candidate may be erased. In the second embodiment, when blank page removal was performed with the blank page removal level update function enabled, the value of the blank page removal level was adjusted, but the value of the blank page removal level may also be adjusted when an image candidate for removal is selected.

[0215] In the second embodiment, when blank page removal is performed with the blank page removal level update function enabled, the value of the blank page removal level is adjusted, but the blank page removal level update function may be enabled all the time.

[0216] In the first embodiment, the preview display processing unit 761 displayed a preview of the image BP of the blank page removal candidate, but it may also display a preview of at least a portion of the image of the scanned document D. The image to be displayed as a preview may be a portion of the image that includes at least all the images of the blank page removal candidate, or all the images of the scanned document, or a portion of the images of all the blank page removal candidate. In short, any display method is acceptable as long as it does not exclude the preview display of all the images of the blank page removal candidate.

[0217] In the first embodiment, when an image BP is selected on the blank page preview screen 130, the selected image BP becomes a blank page removal candidate, and the unselected image BP becomes a non-removal candidate, but the opposite is also possible. In other words, the selected image BP may be switched from a blank page removal candidate to a non-removal candidate, and the unselected image BP may remain a blank page removal candidate.

[0218] In the second embodiment, the configuration may be such that adjusting the blank page removal level by operating the removal level adjustment unit 143 switches the image between being a blank page removal candidate and being a non-removal candidate. In this case, operating the removal level adjustment unit 143 may cause an image to disappear or appear in conjunction with this, or a highlighted display or mark may be added to the image for which the candidate has been switched. For example, the configuration may be such that operating the removal level adjustment units 133, 143 in a direction to increase the blank page removal level causes an image that was previously a blank page removal candidate to appear as a non-removal candidate, and operating the removal level adjustment units 133, 143 in a direction to decrease the blank page removal level causes an image that was previously a non-removal candidate to disappear as a blank page removal candidate.

[0219] In the first and second embodiments, the highlighting when an image is selected is not limited to highlighting a display frame, but may be a mark or symbol superimposed on the image shown in Fig. 21 of the third embodiment. Furthermore, the background color of the image may change, or the image may vibrate or otherwise move.

[0220] In the third embodiment, a mark is added to an image that has been switched from a blank page removal candidate to a non-removal candidate, but a mark may also be added to an image that has been switched from a non-removal candidate to a blank page removal candidate. When the removal level adjustment unit 133, 143 is operated to adjust the blank page removal level, the image is not erased or displayed, or a highlight or mark is not added, but the corresponding page information in the page information display unit 132, 142 on the preview screen 130, 140 may simply be highlighted or a mark is added to indicate the change of candidate.

[0221] When an image is selected, the image may not be highlighted, but may be highlighted or marked to indicate a change in the corresponding page information candidate in the page information display areas 132 and 142.

[0222] The blank preview screen 130 of the first or third embodiment and the preview screen 140 of the second embodiment may be used in combination. In each embodiment, the preview display areas 131 and 141 and the removal level adjustment sections 133 and 143 may be displayed on different screens.

[0223] In the first embodiment, the preview display area 131 and the enlarged display section 136 may be displayed on different screens. In the above embodiments, the preview screens 130, 140 are displayed on the display units 22, 102 of both the image reading device 11 and the host device 100, but they may be displayed on only one of them. For example, the image reading control device 110 may display the preview screens 130, 140 only on the display unit 102 of the host device 100.

[0224] The colors of the histogram HD generated by the histogram generation unit 84 are not limited to the four colors of RGBY. It may be a histogram of three colors of RGB. It may also be a histogram of three colors of YUV. It may also be a histogram of two colors of RG. It may also be a histogram of two colors of RB. It may also be a histogram of two colors of GB. It may also be a single color histogram of one color of RGBYUV. It may also be a single color of grayscale.

[0225] The image reading device may not have an ON / OFF setting for the blank page removal function, and the blank page removal mechanism may always be ON (enabled). The configuration may not include the removal level adjustment units 133 and 143. In this case, the blank page removal level may be set to a predetermined value in advance. Also, the blank page removal level may be updated every time an image BP or PG is selected and removed.

[0226] The conveying unit 31 and the discharging unit 32 do not necessarily have to share a common power source, and the conveying unit 31 and the discharging unit 32 may be driven by separate power sources. For example, the power source for the conveying unit 31 may be a conveying motor, and the power source for the discharging unit 32 may be a discharging motor.

[0227] The image sensor is not limited to a CMOS image sensor, but may be, for example, a MOS (Metal Oxide Semiconductor) image sensor or a CCD (Charge Coupled Device) image sensor.

[0228] The image sensor 42 is not limited to a linear image sensor, but may be an area image sensor. Each functional unit in the computer 60 may be realized not only by software using a CPU and hardware using an ASIC, but also by hardware using an electronic circuit such as an FPGA (field-programmable gate array), or may be realized by either software or hardware.

[0229] The material of the manuscript is not limited to paper, but may be a resin film or sheet, fabric, metal film, etc. Thus, although the term "blank paper" in this specification includes the word "paper" for convenience, "blank paper" also includes materials other than paper.

[0230] The image reading device may be part of a multifunction device that has printing and copying functions in addition to the scanning function. The image reading device is not limited to a sheet-fed type, and may be a flatbed type. In the case of a flatbed type image reading device, a carriage movable in the sub-scanning direction is provided within the main body, and the carriage moves using a scanning motor as a power source, and reads the image of a document set on the glass plate of the document table using a light source and a reading unit provided on the carriage. This type of flatbed type image reading device may also be equipped with an automatic document feeder (auto sheet feeder) that automatically feeds documents. Furthermore, the image reading control method and program for an image reading device can be applied to a flatbed type image reading device, not limited to an image reading device.

[0231] The technical concepts and effects that can be understood from the above-described embodiment and modified examples will be described below. (A) An image reading system comprising an image reading device that reads a document and an image reading control device that controls the image reading device, and a blank page removal function that removes, as blank pages, images of the document read by the image reading device that are candidates for blank page removal and that satisfy a blank page removal level, the system comprising: a preview display processing unit that displays a preview of at least some of the images of the read document on a display unit in a selectable state; a display switching unit that, when the image is selected by operating the input unit, switches the display state of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; a data generation unit that, when the selection state is confirmed by operating the input unit, generates read data based on the remaining image data from the image data of the document after removing image data that is subject to blank page removal, including the confirmed blank page removal candidate; and a blank page removal level setting unit that sets a blank page removal level that allows the confirmed selected image to be a candidate for blank page removal.

[0232] With this configuration, when a user checks the previewed image and selects an image by operating the input unit, the display mode of the image switches to a selection state in which a blank page removal candidate or a non-removal candidate is selected. Also, a blank page removal level appropriate for the selection state of the image from which blank pages are to be removed can be set. Therefore, the user can appropriately select the image from which blank pages are to be removed and set the blank page removal level with simple operations.

[0233] (B) A determination unit is provided that, based on image data of the read document, determines images that satisfy the blank page removal level as candidates for blank page removal and determines images that do not satisfy the blank page removal level as candidates for non-removal, and the preview display processing unit may preview at least a portion of the images of the document that are determined to be candidates for blank page removal on the display unit.

[0234] According to this configuration, at least a part of the images determined to be blank page removal candidates is previewed, so the user can simply select the images they want to remove from the blank page removal candidate images, making it easy for the user to select the images of the blank document they want to remove.

[0235] (C) The preview display processing unit may display a removal level adjustment unit on the display unit that is capable of adjusting the blank page removal level, and when the removal level adjustment unit adjusts the blank page removal level through operation of the input unit, the display switching unit may switch the display mode of the image to a selection state in which the blank page removal candidate or the non-removal candidate is selected in conjunction with the changed blank page removal level.

[0236] According to this configuration, the blank page removal level can be adjusted by the removal level adjustment unit, and the image display mode is switched to a selection state in which a blank page removal candidate or a non-removal candidate is selected in conjunction with the adjusted blank page removal level. Therefore, while adjusting the blank page removal level with the removal level adjustment unit, the user can check the image display mode that switches in conjunction with the adjusted blank page removal level, thereby appropriately selecting the image that the user desires and adjusting to the desired blank page removal level.

[0237] (D) The removal level adjustment section may be a slider that is slid to a position according to the value of the blank page removal level. According to this configuration, when the user slides the slider, the blank page removal level is adjusted to a value corresponding to the slide position, and the image display mode switches to a selection state in which a blank page removal candidate or a non-removal candidate is selected in conjunction with the adjusted blank page removal level. Therefore, the user can easily adjust to the desired blank page removal level. Furthermore, because it is a slide operation, it is easier to visually confirm which overall level and how much adjustment is required compared to inputting a numerical value, so it is possible to easily adjust to an appropriate blank page removal level.

[0238] (E) The preview display processing unit may display an image including at least the non-removal candidate image on the display unit in a selectable state, and when the image is selected by operating the input unit, the display switching unit may switch the display state of the image to a selected state in which the blank removal candidate is selected.

[0239] According to this configuration, the user can select an image to be a candidate for blank page removal from among images displayed on the display unit, including at least non-candidate images, by operating the input unit, and can remove the image as a candidate for blank page removal. In addition, the display mode of the image changes, allowing the user to confirm on the screen of the display unit that the selected image has become an image for blank page removal.

[0240] (F) In conjunction with an operation to reduce the blank page removal level by the removal level adjustment unit, an image that no longer satisfies the blank page removal level may be displayed changed from the blank page removal candidate to the non-removal candidate.

[0241] With this configuration, while the removal level adjustment unit is operating to reduce the blank page removal level, the display mode of the image that changes from a blank page removal candidate to a non-removal candidate in conjunction with the reduced adjustment value of the blank page removal level can be viewed. Therefore, the blank page removal level can be adjusted and the image to be removed as a blank page can be selected appropriately.

[0242] (G) The preview display processing section may display both the image and the removal level adjustment section on the display section in a visibly arranged state. According to this configuration, when the user operates the removal level adjustment unit, the user can appropriately adjust the blank page removal level while checking changes in the image display.

[0243] (H) When the read image is previewed, the preview display processing unit may preview the image based on the most recent blank page removal level that was set at the time when reading of the original document was completed before the image was previewed.

[0244] With this configuration, an image is previewed based on the most recent blank page removal level set when the previous document was read, so an appropriate blank page removal level is more likely to be applied than when the user sets the blank page removal level again before starting to read the current document. This makes it easier to keep the number of operations required for the user to select images as blank page removal candidates to a minimum.

[0245] (I) The preview display processing unit may display page information of the previewed image on the display unit, and when an image is selected from the previewed images by operating the input unit, the display switching unit may highlight the page information corresponding to the image.

[0246] According to this configuration, it is possible to check whether or not an image is selected as a candidate for blank page removal from the page information of the previewed image, making it easy to discover if an image is mistakenly selected as a candidate for blank page removal. (J) The preview display processing unit may display an enlarged image of an image selected by operating the input unit on the display unit.

[0247] According to this configuration, the selected image can be confirmed as an enlarged image, so that it is possible to appropriately determine whether the image is necessary or not, and whether it should be discarded as a blank document. (K) A first selection section may be displayed on the display section, which allows selection of including an image of a textless document as an image of a blank page removal candidate to be displayed on the preview display processing section.

[0248] This configuration allows the user to select whether to preview the image of the textless document, allowing the user to appropriately determine whether the textless document should be discarded as a blank document by viewing the image. This reduces the number of cases where a necessary textless document image is discarded as a blank document against the user's wishes. It also meets the needs of users who do not need to check the textless document image.

[0249] (L) A second selection section that allows selection of not including an image of a document containing text in the images of blank page removal candidates to be displayed by the preview display processing section may be displayed on the display section. According to this configuration, since it is possible to select whether or not to display the image of the document with text, it is possible to select whether or not to display the image of the document with text among the images determined as candidates for blank page removal according to the user's needs. For example, it is possible to eliminate the need to check the blank document on which only the text of the page information is recorded. Furthermore, it is possible to meet the needs of users who want to check the image of the document with text even if it is determined as a candidate for blank page removal.

[0250] (M) When a continuous paper feed mode is executed in which documents for one job are set in multiple batches but are read continuously as one job, the preview display processing unit may display at least a portion of the images on the display unit even during the job when reading of the documents set once is completed, and the blank paper removal level setting unit may be configured to be able to change the blank paper removal level according to the image selected even during the job.

[0251] With this configuration, when the continuous paper feed mode is executed, a preview of at least a portion of the image is displayed even during a job, and the blank page removal level can be changed according to the selected image even during the job. The image read from the next document set during the job can be previewed based on the changed blank page removal level.

[0252] (N) When at least some of the images displayed by the preview display processing unit include images that are non-removal candidates and there are multiple images that have been changed from the non-removal candidates to the blank page removal candidates, the blank page removal level setting unit may set the largest blank page removal level among multiple blank page removal levels that can make each of the multiple images a blank page removal candidate.

[0253] According to this configuration, even if a previewed non-removal candidate image is changed to a blank page removal candidate and there are a plurality of changed images, an appropriate blank page removal level can be set. (O) An image reading control device that controls an image reading device that reads a document, and has a blank page removal function that removes, as blank pages, images that satisfy a blank page removal level from among the images of the document read by the image reading device, and the image reading control device includes: a preview display processing unit that displays a selectable preview of at least some of the images of the document read by the image reading device on a display unit; a display switching unit that, when the image is selected by operating the input unit, switches the display state of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; a data generation unit that, when the selection state is confirmed by operating the input unit, generates read data based on the remaining image data from the image data of the document after removing image data that is subject to blank page removal, including the confirmed blank page removal candidate; and a blank page removal level setting unit that sets a blank page removal level that can make the confirmed selected image a blank page removal candidate. With this configuration, the same effects as those of the image reading system can be obtained.

[0254] (P) An image reading device with a blank page removal function that removes, as blank pages, images that satisfy a blank page removal level from among images read from a document, and that includes: a preview display processing unit that displays a selectable preview of at least some of the images from the read document on a display unit; a display switching unit that switches the display state of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected when the image is selected by operating the input unit; a data generation unit that generates read data based on the remaining image data from the image data of the document after removing image data that is subject to blank page removal, including the confirmed blank page removal candidate, when the selected state is confirmed by operating the input unit; and a blank page removal level setting unit that sets a blank page removal level that can make the confirmed selected image a blank page removal candidate. With this configuration, the same effects as those of an image reading system can be obtained.

[0255] (Q) An image reading method for performing blank page removal processing, in which an image reading device performs blank page removal processing to remove, as blank pages, images that satisfy a blank page removal level from among images read from an original document, the method including: displaying a preview of at least some of the images of the read original document on a display unit in a selectable state; when an image is selected by operating an input unit, switching the display state of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; when the selection state is confirmed by operating the input unit, generating read data based on the remaining image data from which image data to be subjected to blank page removal, including the confirmed blank page removal candidate, has been removed from the image data of the original document; and setting a blank page removal level that can make the confirmed selected image a blank page removal candidate. This method can achieve the same effects as an image reading system.

[0256] (R) A program executed by a computer that realizes a blank page removal function that removes blank pages that meet a blank page removal level from images of a document read by an image reading device, the program causing the computer to execute the following steps: a preview display processing step of displaying a selectable preview of at least some of the images of the document read by the image reading device on a display unit; a display switching step of, when the image is selected by operating the input unit, switching the display state of the image to a selection state in which a blank page removal candidate or a non-removal candidate is selected; a data generation step of, when the selection state is confirmed by operating the input unit, generating read data based on the remaining image data from the image data of the document after removing image data that is subject to blank page removal, including the confirmed blank page removal candidate; and a blank page removal level setting step of setting a blank page removal level that allows the confirmed selected image to be a blank page removal candidate.

[0257] By running this program on a computer, the same effects as those of an image reading system can be achieved. [Explanation of symbols]

[0258] 10...image reading system, 11...image reading device, 12...main body, 13...document support, 18...main body section, 19...cover section, 20...power button, 21...input section, 22...display section, 29...transport path, 30...transport mechanism, 30A...feed section, 31...transport section, 32...discharge section, 33...feed roller, 34...feed roller pair, 35...transport roller pair, 36...discharge roller pair, 37...feed motor, 38...transport motor, 40, 40A, 40B...reading section, 40G...glass plate, 40P...glass surface, 41, 41A, 41B...light source, 42...image sensor, 42A...first image sensor, 42B...second image sensor, 42S...sensor, 43, 43A,43B...background board, 44...encoder, 45...original sensor, 46...original presence / absence sensor, 50...controller, 60...computer, 61...volatile memory, 62...non-volatile memory as an example of a storage unit, 63...input IF, 64...output IF, 65...TG, 66...AFE, 70...main control unit, 71...conveyance control unit, 72...read control unit, 73...image processing unit, 76...display control unit, 761...preview display processing unit, 762...display switching unit, 77...blank page removal setting unit, 78...blank page removal level Setting unit, 79...glass surface dirt detection setting unit, 81...RGB buffer, 82...YUV generation unit, 83...YUV buffer, 84...histogram generation unit, 85...histogram buffer, 86...OCR, 87...blank page determination unit as an example of a determination unit, 88...data generation unit, 881...blank page removal processing unit, 882...file format conversion unit, 91...first setting screen, 92...second setting screen, 93A...slider, 931...first selected unit, 932...second selected unit, 100...host device, 101...input unit, 110...image reading 139...discard button, 140...original preview screen (preview screen), 141...preview display area, 142...page information display area, 143...removal level adjustment area, 143A...slider, ...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142...preview display area, 142... 6...blank page removal button, 147...complete button, 148...discard button, D...original, PR...program, SD1...first management table, SD2...second management table, BT...blank page determination table, SD...read data, HD...histogram, GC...brightness value of the background color of the original, ΔOF...offset amount, LS...brightness threshold, PA...print area, PN...number of pixels in the print area, PS0...threshold (pixel number threshold), BP...image of blank page removal candidate, PG...image, ZP...enlarged image, X...main scanning direction (width direction), Y...sub-scanning direction (conveyance direction).

Claims

1. An image reading system including an image reading device that reads a document and an image reading control device that controls the image reading device, and a blank page removal function that removes blank page removal candidate images that have been determined to be blank documents from among images of the document read by the image reading device, a blank page determination unit that, when the size of the document read by the image reading device is a first size and the resolution at which the document is read by the image reading device is a first resolution, determines, based on image data of the document read by the image reading device, a document that satisfies a blank page determination condition in which the number of pixels that are a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases, as a blank page removal candidate, and determines a document that does not satisfy the blank page determination condition as a non-removal candidate; a preview display processing unit that displays a selectable preview of at least a part of the images of the originals read by the image reading device on a display unit; a display switching unit that, when an image of a document to be previewed by the preview display processing unit is selected by operating an input unit, switches the display mode of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; a data generating unit that, when the selection state is confirmed by operating the input unit, generates read data based on image data of the remaining document after removing image data of the document that has been read by the image reading device and that has been confirmed as a candidate for blank page removal; a blank page removal level setting unit that sets a blank page removal level at which the image to be blank page removal is determined as a blank page removal candidate by the blank page determination unit, The image reading system is characterized in that the preview display processing section displays an enlarged image of an image selected by operating the input section on the display section.

2. An image reading system including an image reading device that reads a document and an image reading control device that controls the image reading device, and a blank page removal function that removes blank page removal candidate images that have been determined to be blank documents from among images of the document read by the image reading device, a blank page determination unit that, when the size of the document read by the image reading device is a first size and the resolution at which the document is read by the image reading device is a first resolution, determines, based on image data of the document read by the image reading device, a document that satisfies a blank page determination condition in which the number of pixels that are a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases, as a blank page removal candidate, and determines a document that does not satisfy the blank page determination condition as a non-removal candidate; a preview display processing unit that displays a selectable preview of at least a part of the images of the originals read by the image reading device on a display unit; a display switching unit that, when an image of a document to be previewed by the preview display processing unit is selected by operating an input unit, switches the display mode of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; a data generating unit that, when the selection state is confirmed by operating the input unit, generates read data based on image data of the remaining document after removing image data of the document that has been read by the image reading device and that has been confirmed as a candidate for blank page removal; a blank page removal level setting unit that sets a blank page removal level at which the image to be blank page removal is determined as a blank page removal candidate by the blank page determination unit, The image reading system is characterized in that the preview display processing unit displays a preview of images of at least some of the documents read by the image reading device that have been determined to be candidates for blank page removal on the display unit, and displays a first selection unit on the display unit that can be selected by operating the input unit to include an image of a document without text in the previewed images of the candidates for blank page removal.

3. An image reading system including an image reading device that reads a document and an image reading control device that controls the image reading device, and a blank page removal function that removes blank page removal candidate images that have been determined to be blank documents from among images of the document read by the image reading device, a blank page determination unit that, when the size of the document read by the image reading device is a first size and the resolution at which the document is read by the image reading device is a first resolution, determines, based on image data of the document read by the image reading device, a document that satisfies a blank page determination condition in which the number of pixels that are a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases, as a blank page removal candidate, and determines a document that does not satisfy the blank page determination condition as a non-removal candidate; a preview display processing unit that displays a selectable preview of at least a part of the images of the originals read by the image reading device on a display unit; a display switching unit that, when an image of a document to be previewed by the preview display processing unit is selected by operating an input unit, switches the display mode of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; a data generating unit that, when the selection state is confirmed by operating the input unit, generates read data based on image data of the remaining document after removing image data of the document that has been read by the image reading device and that has been confirmed as a candidate for blank page removal; a blank page removal level setting unit that sets a blank page removal level at which the image to be blank page removal is determined as a blank page removal candidate by the blank page determination unit, The image reading system is characterized in that the preview display processing unit displays a preview of images of at least some of the documents read by the image reading device that have been determined to be candidates for blank page removal on the display unit, and displays a second selection unit on the display unit that can be selected by operating the input unit to exclude images of documents without text from the previewed images of the candidates for blank page removal.

4. An image reading system including an image reading device that reads at least one document placed on a document support, and an image reading control device that controls the image reading device, and a blank page removal function that removes images of the documents read by the image reading device that are determined to be blank documents and are candidates for blank page removal, a blank page determination unit that, when the size of the document read by the image reading device is a first size and the resolution at which the document is read by the image reading device is a first resolution, determines, based on image data of the document read by the image reading device, a document that satisfies a blank page determination condition in which the number of pixels that are a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases, as a blank page removal candidate, and determines a document that does not satisfy the blank page determination condition as a non-removal candidate; a preview display processing unit that displays a selectable preview of at least a part of the images of the originals read by the image reading device on a display unit; a display switching unit that, when an image of a document to be previewed by the preview display processing unit is selected by operating an input unit, switches the display mode of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; a data generating unit that, when the selection state is confirmed by operating the input unit, generates read data based on image data of the remaining document after removing image data of the document that has been read by the image reading device and that has been confirmed as a candidate for blank page removal; a blank page removal level setting unit that sets a blank page removal level at which the image to be blank page removal is determined as a blank page removal candidate by the blank page determination unit, the preview display processing unit, when generating one piece of read data including image data read in a first job and image data read in a second job after the first job, displays at least a portion of the image on the display unit at a timing when the first job is completed, in a case where one job is defined as a period until the document sensor detects that the documents set on the document support have been removed; The image reading system is characterized in that the blank page removal level setting unit is configured to be able to change the blank page removal level in accordance with an image of a blank page removal candidate selected at the timing when the first job is completed.

5. An image reading system including an image reading device that reads a document and an image reading control device that controls the image reading device, and a blank page removal function that removes blank page removal candidate images that have been determined to be blank documents from among images of the document read by the image reading device, a blank page determination unit that, when the size of the document read by the image reading device is a first size and the resolution at which the document is read by the image reading device is a first resolution, determines, based on image data of the document read by the image reading device, a document that satisfies a blank page determination condition in which the number of pixels that are a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases, as a blank page removal candidate, and determines a document that does not satisfy the blank page determination condition as a non-removal candidate; a preview display processing unit that displays a selectable preview of at least a part of the images of the originals read by the image reading device on a display unit; a display switching unit that, when an image of a document to be previewed by the preview display processing unit is selected by operating an input unit, switches the display mode of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; a data generating unit that, when the selection state is confirmed by operating the input unit, generates read data based on image data of the remaining document after removing image data of the document that has been read by the image reading device and that has been confirmed as a candidate for blank page removal; a blank page removal level setting unit that sets a blank page removal level at which the image to be blank page removal is determined as a blank page removal candidate by the blank page determination unit, an image reading system characterized in that at least some of the images displayed by the preview display processing unit include images that are non-removal candidates, and when there are multiple images that have been changed from non-removal candidates to blank page removal candidates, the blank page removal level setting unit sets the largest blank page removal level among multiple blank page removal levels that can make each of the multiple images a blank page removal candidate.

6. the preview display processing unit displays a removal level adjustment unit on the display unit, the removal level adjustment unit being capable of adjusting the blank page removal level; 3. The image reading system according to claim 1, wherein when the removal level adjustment unit changes the blank page removal level through operation of the input unit, the display switching unit switches the display mode of the image to the selected state based on the determination result by the blank page determination unit in conjunction with the changed blank page removal level.

7. 7. The image reading system according to claim 6, wherein the removal level adjustment unit is a slider that is slid to a position according to the value of the blank page removal level.

8. The image reading system according to claim 6 or 7, wherein the display switching unit is linked to an operation of decreasing the blank page removal level by the removal level adjustment unit through an operation on the input unit, and switches an image of a document that no longer satisfies the blank page determination condition based on the determination result by the blank page determination unit from the blank page removal candidate to the non-removal candidate.

9. The image reading system according to claim 8, characterized in that the preview display processing unit displays on the display unit both an image of at least a portion of the document read by the image reading device and the removal level adjustment unit in a visible state.

10. the preview display processing unit displays, on the display unit, an image including at least the non-removal candidate image in a selectable state; The image reading system according to any one of claims 1 to 9, characterized in that when the image is selected by operating the input unit, the display switching unit switches the display state of the image to a selected state in which the blank page removal candidate is selected.

11. the blank page removal level setting unit sets a blank page removal level when the selected state is confirmed by operating the input unit, The image reading system according to any one of claims 1 to 10, characterized in that when the read image is previewed, the preview display processing unit displays a preview of at least a portion of the images of the original document read by the image reading device in a selectable state based on the most recent blank page removal level that was set when the selection state was confirmed before the image was previewed.

12. the preview display processing unit displays page information of the previewed image on the display unit; The image reading system according to any one of claims 1 to 11, characterized in that when an image is selected from the previewed images by operating the input unit, the display switching unit highlights the page information corresponding to the image.

13. An image reading device having a blank page removal function that removes images of blank page removal candidates that have been determined to be blank documents from images obtained by reading a document, a blank page determination unit that, when the size of the document to be read is a first size and the resolution at which the document is read is a first resolution, determines, based on image data of the read document, a document that satisfies a blank page determination condition that the number of pixels having a density that is a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases, as a blank page removal candidate, and determines a document that does not satisfy the blank page determination condition as a non-removal candidate; a preview display processing unit that displays a preview of at least a part of the scanned document images on a display unit in a selectable state; a display switching unit that, when an image of a document to be previewed by the preview display processing unit is selected by operating an input unit, switches the display mode of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; a data generating unit that, when the selection state is confirmed by operating the input unit, generates read data based on image data of the remaining document after removing image data of the scanned document that is the target of blank page removal and that has been confirmed as a candidate for blank page removal; a blank page removal level setting unit that sets a blank page removal level at which the image to be blank page removal is determined as a blank page removal candidate by the blank page determination unit, The image reading device is characterized in that the preview display processing section displays an enlarged image of an image selected by operating the input section on the display section.

14. An image reading device having a blank page removal function that removes images of blank page removal candidates that have been determined to be blank documents from images obtained by reading a document, a blank page determination unit that, when the size of the document to be read is a first size and the resolution at which the document is read is a first resolution, determines, based on image data of the read document, a document that satisfies a blank page determination condition that the number of pixels having a density that is a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases, as a blank page removal candidate, and determines a document that does not satisfy the blank page determination condition as a non-removal candidate; a preview display processing unit that displays a preview of at least a part of the scanned document images on a display unit in a selectable state; a display switching unit that, when an image of a document to be previewed by the preview display processing unit is selected by operating an input unit, switches the display mode of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; a data generating unit that, when the selection state is confirmed by operating the input unit, generates read data based on image data of the remaining document after removing image data of the scanned document that is the target of blank page removal and that has been confirmed as a candidate for blank page removal; a blank page removal level setting unit that sets a blank page removal level at which the image to be blank page removal is determined as a blank page removal candidate by the blank page determination unit, The image reading device is characterized in that the preview display processing unit displays a preview of images of at least some of the scanned documents that have been determined to be candidates for blank page removal on the display unit, and displays a first selection unit on the display unit that can be selected by operating the input unit to include an image of a document without text in the previewed images of the candidates for blank page removal.

15. An image reading device having a blank page removal function that removes images of blank page removal candidates that have been determined to be blank documents from images obtained by reading a document, a blank page determination unit that, when the size of the document to be read is a first size and the resolution at which the document is read is a first resolution, determines, based on image data of the read document, a document that satisfies a blank page determination condition that the number of pixels having a density that is a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases, as a blank page removal candidate, and determines a document that does not satisfy the blank page determination condition as a non-removal candidate; a preview display processing unit that displays a preview of at least a part of the scanned document images on a display unit in a selectable state; a display switching unit that, when an image of a document to be previewed by the preview display processing unit is selected by operating an input unit, switches the display mode of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; a data generating unit that, when the selection state is confirmed by operating the input unit, generates read data based on image data of the remaining document after removing image data of the scanned document that is the target of blank page removal and that has been confirmed as a candidate for blank page removal; a blank page removal level setting unit that sets a blank page removal level at which the image to be blank page removal is determined as a blank page removal candidate by the blank page determination unit, The preview display processing unit displays a preview of images of at least some of the scanned documents that have been determined to be candidates for blank page removal on the display unit, and displays a second selection unit on the display unit that can be selected by operating the input unit to exclude images of documents without text from the previewed images of the candidates for blank page removal.

16. An image reading device having a blank page removal function for removing an image of a blank page removal candidate determined as a blank page from images obtained by reading at least one document placed on a document support, a blank page determination unit that, when the size of the document to be read is a first size and the resolution at which the document is read is a first resolution, determines, based on image data of the read document, a document that satisfies a blank page determination condition that the number of pixels having a density that is a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases, as a blank page removal candidate, and determines a document that does not satisfy the blank page determination condition as a non-removal candidate; a preview display processing unit that displays a preview of at least a part of the scanned document images on a display unit in a selectable state; a display switching unit that, when an image of a document to be previewed by the preview display processing unit is selected by operating an input unit, switches the display mode of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; a data generating unit that, when the selection state is confirmed by operating the input unit, generates read data based on image data of the remaining document after removing image data of the scanned document that is the target of blank page removal and that has been confirmed as a candidate for blank page removal; a blank page removal level setting unit that sets a blank page removal level at which the image to be blank page removal is determined as a blank page removal candidate by the blank page determination unit, the preview display processing unit, when generating one piece of read data including image data read in a first job and image data read in a second job after the first job, displays at least a portion of the image on the display unit at a timing when the first job is completed, in a case where one job is defined as a period until the document sensor detects that the documents set on the document support have been removed; The image reading device according to claim 1, wherein the blank page removal level setting unit is configured to be able to change the blank page removal level in accordance with an image of a blank page removal candidate selected at the timing when the first job is completed.

17. An image reading device having a blank page removal function that removes images of blank page removal candidates that have been determined to be blank documents from images obtained by reading a document, a blank page determination unit that, when the size of the document to be read is a first size and the resolution at which the document is read is a first resolution, determines, based on image data of the read document, a document that satisfies a blank page determination condition that the number of pixels having a density that is a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases, as a blank page removal candidate, and determines a document that does not satisfy the blank page determination condition as a non-removal candidate; a preview display processing unit that displays a preview of at least a part of the scanned document images on a display unit in a selectable state; a display switching unit that, when an image of a document to be previewed by the preview display processing unit is selected by operating an input unit, switches the display mode of the image to a selected state in which a blank page removal candidate or a non-removal candidate is selected; a data generating unit that, when the selection state is confirmed by operating the input unit, generates read data based on image data of the remaining document after removing image data of the scanned document that is the target of blank page removal and that has been confirmed as a candidate for blank page removal; a blank page removal level setting unit that sets a blank page removal level at which the image to be blank page removal is determined as a blank page removal candidate by the blank page determination unit, An image reading device characterized in that at least some of the images displayed by the preview display processing unit include images that are non-removal candidates, and when there are multiple images that have been changed from non-removal candidates to blank page removal candidates, the blank page removal level setting unit sets the largest blank page removal level among multiple blank page removal levels that can make each of the multiple images a blank page removal candidate.

18. An image reading method for performing a blank page removal process to remove images determined to be blank documents from images read by an image reading device, the method comprising: When the size of the document read by the image reading device is a first size and the resolution at which the image reading device reads the document is a first resolution, based on the image data of the document read by the image reading device, a document that satisfies a blank page determination condition in which the number of pixels having a density that is a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases is determined as a blank page removal candidate, and a document that does not satisfy the blank page determination condition is determined as a non-removal candidate; previewing, on a display unit, images of at least a part of the documents read by the image reading device in a selectable manner; When an image of a document to be previewed is selected by operating an input unit, the display mode of the image is switched to a selected state in which a blank page removal candidate or a non-removal candidate is selected; When the selection state is confirmed by operating the input unit, generating read data based on image data of the remaining document after removing image data of the document that is the target of blank page removal and that has been confirmed as a candidate for blank page removal from the image data of the document that has been read by the image reading device; setting a blank page removal level at which the image to be subjected to blank page removal in the selected state that has been confirmed as a blank page removal candidate is determined to be a blank page removal candidate, The image reading method according to the present invention, wherein the preview display includes displaying an enlarged image of an image selected by operating the input unit on the display unit.

19. An image reading method for performing a blank page removal process to remove images determined to be blank documents from images read by an image reading device, the method comprising: When the size of the document read by the image reading device is a first size and the resolution at which the image reading device reads the document is a first resolution, based on the image data of the document read by the image reading device, a document that satisfies a blank page determination condition in which the number of pixels having a density that is a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases is determined as a blank page removal candidate, and a document that does not satisfy the blank page determination condition is determined as a non-removal candidate; previewing, on a display unit, images of at least a part of the documents read by the image reading device in a selectable manner; When an image of a document to be previewed is selected by operating an input unit, the display mode of the image is switched to a selected state in which a blank page removal candidate or a non-removal candidate is selected; When the selection state is confirmed by operating the input unit, generating read data based on image data of the remaining document after removing image data of the document that is the target of blank page removal and that has been confirmed as a candidate for blank page removal from the image data of the document that has been read by the image reading device; setting a blank page removal level at which the image to be subjected to blank page removal in the selected state that has been confirmed as a blank page removal candidate is determined to be a blank page removal candidate, The preview display is previewing, on the display unit, images of at least some of the documents determined to be candidates for blank page removal among the documents read by the image reading device; An image reading method characterized by including displaying on the display unit a first selection section that can be selected by operating the input section to include an image of a textless document in an image of a candidate for blank page removal that is displayed as a preview.

20. An image reading method for performing a blank page removal process to remove images determined to be blank documents from images read by an image reading device, the method comprising: When the size of the document read by the image reading device is a first size and the resolution at which the image reading device reads the document is a first resolution, based on the image data of the document read by the image reading device, a document that satisfies a blank page determination condition in which the number of pixels having a density that is a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases is determined as a blank page removal candidate, and a document that does not satisfy the blank page determination condition is determined as a non-removal candidate; previewing, on a display unit, images of at least a part of the documents read by the image reading device in a selectable manner; When an image of a document to be previewed is selected by operating an input unit, the display mode of the image is switched to a selected state in which a blank page removal candidate or a non-removal candidate is selected; When the selection state is confirmed by operating the input unit, generating read data based on image data of the remaining document after removing image data of the document that is the target of blank page removal and that has been confirmed as a candidate for blank page removal from the image data of the document that has been read by the image reading device; setting a blank page removal level at which the image to be subjected to blank page removal in the selected state that has been confirmed as a blank page removal candidate is determined to be a blank page removal candidate, The preview display is previewing, on the display unit, images of at least some of the documents determined to be candidates for blank page removal among the documents read by the image reading device; and displaying on the display unit a second selection section that can be selected by operating the input section so that images of textless documents are not included in the previewed images of blank page removal candidates.

21. An image reading method for performing a blank page removal process to remove images determined to be blank documents from images read by an image reading device, the method comprising: When the size of the document read by the image reading device is a first size and the resolution at which the image reading device reads the document is a first resolution, based on the image data of the document read by the image reading device, a document that satisfies a blank page determination condition in which the number of pixels having a density that is a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases is determined as a blank page removal candidate, and a document that does not satisfy the blank page determination condition is determined as a non-removal candidate; previewing, on a display unit, images of at least a part of the documents read by the image reading device in a selectable manner; When an image of a document to be previewed is selected by operating an input unit, the display mode of the image is switched to a selected state in which a blank page removal candidate or a non-removal candidate is selected; When the selection state is confirmed by operating the input unit, generating read data based on image data of the remaining document after removing image data of the document that is the target of blank page removal and that has been confirmed as a candidate for blank page removal from the image data of the document that has been read by the image reading device; setting a blank page removal level at which the image to be subjected to blank page removal in the selected state that has been confirmed as a blank page removal candidate is determined to be a blank page removal candidate, The preview display includes, when one job is defined as a period until the document sensor detects that the documents set on the document support have been removed, displaying at least a portion of the image on the display unit at the timing when the first job is completed, when generating one piece of read data including image data read in a first job and image data read in a second job after the first job, an image reading method characterized in that setting the blank page removal level includes being configured to be able to change the blank page removal level in accordance with an image of a blank page removal candidate selected at the timing when the first job is completed.

22. An image reading method for performing a blank page removal process to remove images determined to be blank documents from images read by an image reading device, the method comprising: When the size of the document read by the image reading device is a first size and the resolution at which the image reading device reads the document is a first resolution, based on the image data of the document read by the image reading device, a document that satisfies a blank page determination condition in which the number of pixels having a density that is a predetermined density or more darker than the background color of the document is equal to or less than a threshold value that increases as the blank page removal level increases is determined as a blank page removal candidate, and a document that does not satisfy the blank page determination condition is determined as a non-removal candidate; previewing, on a display unit, images of at least a part of the documents read by the image reading device in a selectable manner; When an image of a document to be previewed is selected by operating an input unit, the display mode of the image is switched to a selected state in which a blank page removal candidate or a non-removal candidate is selected; When the selection state is confirmed by operating the input unit, generating read data based on image data of the remaining document after removing image data of the document that is the target of blank page removal and that has been confirmed as a candidate for blank page removal from the image data of the document that has been read by the image reading device; setting a blank page removal level at which the image to be subjected to blank page removal in the selected state that has been confirmed as a blank page removal candidate is determined to be a blank page removal candidate, An image reading method characterized in that, when at least some of the images displayed in preview include images that are candidates for non-removal, and there are multiple images that have been changed from non-removal candidates to blank page removal candidates, setting the blank page removal level includes setting the largest blank page removal level among multiple blank page removal levels that can make each of the multiple images a candidate for blank page removal.

Images