Image forming apparatus, control method and program

Abstract

To provide an image processing apparatus, a control method, and a program that can certainly detect a document image in an image forming apparatus that reads a document by a skim reading method.SOLUTION: An automatic document feeder of an image forming apparatus includes a light transmission member 16 provided at a reading position P1 set on a conveyance path 40 and a reading opposite plate 26 opposite thereto, and a document being conveyed passes through between the opposite plate and the light transmission member. On a surface of the opposite plate 26 opposite to the light transmission member 16, a low lightness area in for example gray, and a high lightness area in for example white having higher lightness than the low lightness area are formed adjacent to each other in a conveyance direction of the document. An image reading section 12 sets a home position of a scanning unit 52 to a first position or a second position corresponding to either one of the low lightness area or the high lightness area, and reads the document passing through the reading position P1.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to an image forming apparatus, a control method, and a program, and more particularly to an image forming apparatus, a control method, and a program having a crop function. [Background technology]

[0002] An example of this type of technology is disclosed in Patent Document 1. In the technology disclosed in Patent Document 1, a document image obtained by scanning a document placed on a document platen is cropped, but if the detection of the document image fails, a warning screen is displayed prompting the user to rearrange the document on the document platen.

[0003] On the other hand, a configuration is known in which an image on the front side of a document being automatically transported is read at a reading position, that is, a document image is read by a so-called skimming method, as shown in Patent Document 2. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-201767 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-86988 Summary of the Invention [Problem to be solved by the invention]

[0005] The technology of Patent Document 1 cannot be applied to a skimming method such as Patent Document 2.

[0006] SUMMARY OF THE INVENTION Therefore, a primary object of the present invention is to provide a novel image forming apparatus, a control method, and a program.

[0007] Another object of the present invention is to provide an image forming apparatus, a control method, and a program that can detect an original image using a skimming method. [Means for solving the problem]

[0013] First Example indicates the reading position set on the transport path. By the image reading unit provided in The image forming apparatus is a flow-reading type image forming apparatus that reads an original by irradiating the original with light from a scanning unit, and includes a transport unit that transports the original along a transport path, a light-transmitting member that is provided below the transport path at a reading position, an opposing plate that is provided opposite the light-transmitting member and through which the original being transported passes between the opposing plate and the light-transmitting member, the opposing plate having a low-lightness region and a high-lightness region having a lightness higher than the low-lightness region formed adjacent to the original transport direction on the opposing surface with the light-transmitting member, a first-time reading execution unit that sets the home position of the scanning unit to a position corresponding to the low-lightness region and reads the original passing through the reading position with the image reading unit, a judgment unit that judges whether the original image can be detected from image data obtained by the first reading by the first-time reading execution unit, and a second-time reading execution unit that sets the home position of the scanning unit to a position corresponding to the high-lightness region and reads the original passing through the reading position with the image reading unit when the judgment unit judges that the original image cannot be detected from the image data.

[0014] First Example In this case, the image forming apparatus (10) is set at a reading position (P1) on the conveying path (40). By the image reading unit provided inThe image forming apparatus is a flow-reading type that reads an original (100) by irradiating the original (100) with light from a scanning unit (52). A transport unit (38) transports the original (100) along a transport path. A light-transmitting member (16) is provided below the transport path at a reading position (P1), and a counter plate (26) is provided facing the light-transmitting member. The original passes between the counter plate and the light-transmitting member during transport. A low-lightness region (26G), such as gray, and a high-lightness region (26W), such as white, having a lightness higher than the low-lightness region, are formed adjacent to each other in the transport direction of the original on the surface of the counter plate (26) facing the light-transmitting member. A first-time reading execution unit (76, 12, S1, S31) sets the home position of the scanning unit (52) to a first position corresponding to the low-lightness region (26G), and reads the original passing through the reading position with an image reading unit. The determination unit (76, 28, S5, S33) determines whether the document image has been detected from the image data obtained by the first reading by the first reading execution unit. Then, the second reading execution unit (76, 12, S15, S59) sets the home position of the scanning unit (52) to a second position corresponding to the high-brightness area (26W), and reads the document passing through the reading position by the image reading unit.

[0015] First Example According to the method, when a reading is performed by a first reading execution unit in which the home position of the scanning unit is set to a first position corresponding to a low-brightness area and the original image cannot be detected from the read image data, the home position of the scanning unit is set to a second position corresponding to a high-brightness area and a second reading is performed by a second reading execution unit, thereby enabling the original image to be detected reliably.

[0016] Second Example indicates the reading position set on the transport path. By the image reading unit provided inan image forming apparatus of a flow-reading type that reads an original by irradiating the original with light from a scanning unit, the image forming apparatus including a transport section that transports the original along a transport path, a light-transmitting member provided below the transport path at a reading position, and an opposing plate that is provided opposite the light-transmitting member and through which the original being transported passes between the light-transmitting member and the opposing plate, the opposing plate having a low-lightness region and a high-lightness region having a lightness higher than the low-lightness region formed adjacent to the original transport direction on a surface opposing the light-transmitting member, the image forming apparatus including: a first-time reading execution step of setting a home position of the scanning unit to a position corresponding to the low-lightness region, and reading the original passing the reading position by the image reading section; a determination step of determining whether an original image has been detected from image data obtained by the first reading by the first-time reading execution section; Decision Step When it is determined that the original image cannot be detected from the image data, the home position of the scanning unit is set to a position corresponding to a high-brightness area, and a second reading execution step is performed in which the image reading unit reads the original passing through the reading position.

[0017] Second Example According to First Example Similarly, the document image can be detected reliably.

[0018] Third Example indicates the reading position set on the transport path. By the image reading unit provided inIn an image forming apparatus of a flow-reading type that reads an original by irradiating the original with light from a scanning unit, the image forming apparatus is provided with a transport unit that transports the original along a transport path, a light-transmitting member that is provided below the transport path at a reading position, and an opposing plate that is provided opposite the light-transmitting member and through which the original being transported passes between the light-transmitting member and the opposing plate, and on the surface facing the light-transmitting member, a low-lightness region and a high-lightness region having a lightness higher than the low-lightness region are formed adjacent to the transport direction of the original. In this image forming apparatus, a program for the image forming apparatus causes a computer of the image forming apparatus to function as a first-time reading execution unit that sets the home position of the scanning unit to a position corresponding to the low-lightness region and reads the original passing through the reading position with the image reading unit, a judgment unit that judges whether the original image can be detected from image data obtained by the first reading by the first-time reading execution unit, and a second-time reading execution unit that sets the home position of the scanning unit to a position corresponding to the high-lightness region and reads the original passing through the reading position with the image reading unit when the judgment unit determines that the original image cannot be detected from the image data.

[0019] Third Example According to First Example Similarly, the document image can be detected reliably. [Effects of the Invention]

[0020] According to this invention, the opposing plate at the reading position forms two areas with a brightness difference in the document transport direction (the sub-scanning direction of the scanning unit), so that by appropriately setting the home position of the document scanning unit, the document image can be reliably detected. [Brief explanation of the drawings]

[0021] [Figure 1] FIG. 1 is a diagram illustrating an image forming apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram illustrating an example of an automatic document feeder in this embodiment. [Figure 3] FIG. 3 is a diagram illustrating the configuration of the automatic document feeder and the image reading unit in the embodiment. [Figure 4] FIG. 4 is a diagram showing an example of the reading counter plate used in this embodiment. [Figure 5] FIG. 5 is an enlarged diagram showing the configuration in the vicinity of the opposing plate. [Figure 6] FIG. 6 is a diagram showing a first position of the scanning unit when the opposing plate of the embodiment of FIG. 5 is used. [Figure 7] FIG. 7 is a diagram showing a second position of the scanning unit when the opposing plate of the embodiment of FIG. 5 is used. [Figure 8] FIG. 8 is an illustrative view showing a case where document image detection (cropping process) for one document is successful in this embodiment. [Figure 9] Figure 9 is an illustration showing the case where document image detection (cropping processing) is successful on the second reading in this embodiment, where Figure 9(A) shows the case where the first reading failed, and Figure 9(B) shows the case where the second reading was successful. [Figure 10] FIG. 10 is an illustrative view showing one example of an error screen notifying failure in document image detection (cropping process). [Figure 11] FIG. 11 is a block diagram showing an example of the electrical configuration of the image forming apparatus of this embodiment. [Figure 12] FIG. 12 is an illustrative view showing an example of a memory map of the main storage unit of FIG. [Figure 13] FIG. 13 is a flowchart showing an example of the operation of image processing (cropping) in this embodiment when there is only one document. [Figure 14] FIG. 14 is a flow chart showing part of the image processing (cropping) operation in this embodiment when there are multiple originals. [Figure 15] FIG. 15 is a flowchart showing the remaining part of the image processing (cropping) operation when there are multiple originals in this embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0022] 1, an image forming apparatus 10 according to an embodiment of the present invention is, for example, a multifunction peripheral (MFP) that has multiple functions such as a copy function, an image scanner function, a printer function, a fax function, etc. However, the present invention can be applied to an image forming apparatus that has at least a document reading function of a so-called skimming type that reads documents fed one by one from a document table.

[0023] An image reading unit 12, an example of an image reading means, is provided at the top of the image forming apparatus 10. As will be described in detail later, this image reading unit 12 reads an image of a document (not shown) and outputs document image data. The image reading unit 12 includes a transparent document table 14 on which the document is placed and a transparent reading glass 16 provided in a fixed position (in a flow reading mode) to the left of the document table 14. Note that this reading glass 16 may also be referred to as an SPF glass if the automatic document feeder provided in the document table cover 20 (described later) is a so-called SPF (Single Pass Feeder) type. Although referred to as a reading glass 16 here, it may be made of transparent plastic instead of glass, and the concept of the reading glass 16 should be understood to include such transparent plastic materials. In other words, the reading glass 16 can be considered a light-transmitting member at the reading position.

[0024] An operation unit 18 is provided on the upper part of the image forming apparatus 10, in front of the image reading unit 12. On the operation surface of this operation unit 18, for example, a display 19 with a touch panel is provided.

[0025] The document table cover 20 is provided above the image reading unit 12, for example, on one side of the document table 14 at the rear side, using a hinge, so as to be able to open and close. A document holder 22 for holding down a document placed on the document table 14 is provided on the underside of the document table cover 20. A (reading) opposing plate 26 is provided to the left of the document holder 22, facing the reading glass 16. As will be explained later, this embodiment is characterized by this opposing plate 26.

[0026] An image forming unit 30, which is an example of an image forming means, is provided below the image reading unit 12. The image forming unit 30 prints an image based on image data after image processing by an image processing unit 28 (FIG. 11), such as extracting (detecting) an original image and performing cropping, onto paper (sheets) as a recording medium. This image formation process is performed, for example, by a known electrophotographic method. For this reason, the image forming unit 30 includes image formation components such as a photosensitive drum, as is already well known.

[0027] A paper feed unit 31, which is an example of a paper feed means, is provided below the image forming unit 30. In this embodiment, the paper feed unit 31 has four paper feed cassettes 31a. Each paper feed cassette 31a stores paper of a predetermined size in a predetermined orientation. Although not shown, a manual feed tray is provided on the right side of the image forming apparatus 10. The paper feed unit 20 supplies paper (sheets) to the image forming unit 30 one sheet at a time, using either one of the paper feed cassettes 31a or the manual feed tray as the paper feed source.

[0028] The paper fed from the paper feed unit 31 and having an image printed thereon by the image forming unit 16 is discharged to a paper discharge tray 32. In this embodiment, the paper discharge tray 32 is provided in the internal space between the image forming unit 30 and the image reading unit 12. 2, an original placement tray 34 is formed on the upper surface of the platen cover 20. The original placement tray 34 is provided with original guides 36 that regulate both sides of an original 100 (FIG. 3) placed thereon.

[0029] The automatic document feeder 38, which is provided inside the document platen cover 20 and constitutes the document transport section, is an ADF (Automatic Document Feeder) or the aforementioned SPF, and as shown in Fig. 3, transports the documents 100 stacked on the document placement tray 34 one by one through a document transport path 40 to a document discharge tray 42. In other words, the document transport path 40 leads from a paper feed opening 44 of the document placement tray 34 to a paper discharge opening 46 on the document discharge tray 42 side.

[0030] A pickup roller 48 is provided near the paper feed opening 44 of the document transport path 40 to pick up the documents 100 placed on the document placement tray 34 one by one. The documents 100 picked up from the document placement tray 34 by the pickup roller 48 are taken into the document transport path 40 from the paper feed opening 44. For this purpose, a paper feed roller pair 49 is provided at the end of the document transport path 40 on the paper feed opening 44 side.

[0031] A plurality of pairs of transport rollers are provided at appropriate positions in the document transport path 40. These pairs of transport rollers transport the document 100 taken into the document transport path 40 along the document transport path 40 (so as to follow the path).

[0032] The document transport path 40 has a portion that contacts the upper surface of the reading glass 16 on the left of the document table 14, and the reading position P1 of the image reading unit 12 is set at the portion between the reading glass 16 and the reading counter plate 26 that faces it.

[0033] That is, when the original 100 is transported along the original transport path 40, the original 100 passes through the reading position P1 along the way. As a result, the image on the front side of the original 100 is read by a so-called flow reading method. Incidentally, just before the reading position P1 in the transport direction of the original 100 (the closest position on the upstream side), a registration roller 50 is provided to adjust the timing of supplying the original 100 to the reading position P1.

[0034] As described above, the image reading unit 12 has a housing with a transparent document placement table 14 provided on the upper surface, and a scanning unit 52 that can move (scan) in the main scanning direction and the sub-scanning direction is provided inside the housing. The main scanning direction is the direction perpendicular to the paper surface in FIG. 3, and the sub-scanning direction is the direction perpendicular to the paper surface in FIG. 3 (the document transport direction). The scanning unit 52 includes a light source 53 that irradiates (exposes) the surface of the document 100 with light and a mirror 54 that reflects the light reflected from the document surface irradiated by the light source 53. The image reading unit 12 further includes an imaging lens 56 that receives the light reflected from the document that has been reflected by the mirror 54 of the scanning unit 52, a reading sensor (line sensor) 58, etc.

[0035] When the image on the surface of the original 100 is read by the image reading section 12, the light source 53 of the scanning unit 52 exposes the surface of the original 100 at the reading position P1, and the light reflected from the original surface is reflected by the mirror 54 and directed to the imaging lens 56. The imaging lens 56 then forms an image of the reflected light on a light-receiving element (not shown) of the reading sensor 58. The reading sensor 58, such as a CCD (Charge Coupled Device), detects the luminance and chromaticity of the formed reflected light and generates image data including the original image and a background color image formed by the opposing plate 26.

[0036] The image reading unit 12 is capable of fixed reading, which reads the image of a document placed on a document table 14, and flow reading, which reads the image of a document 100 conveyed on a document conveying path 40 by an automatic document feeder .

[0037] In the case of fixed reading, the image reading unit 12 reads the document image while moving the scanning unit 52, which includes a light source 53 and multiple mirrors 54, in the main scanning direction and the sub-scanning direction below the document placing table 14. At this time, the document holder 22 (FIG. 1) becomes the background color of the document. Generally, the color of the document holder 22, i.e., the background color in the case of fixed reading, is white.

[0038] On the other hand, in the case of skimming, the image reading section 12 has the scanning unit 52 waiting below the document reading position P1, which is the home position, and when the document 100 conveyed by the document feeder 38 passes the reading position P1, the image of the document 100 is read by irradiating the surface of the document 100 with light from the light source 53 through the reading glass 16. At this time, the reading counter plate 26 forms the background color of the document passing the reading position P1.

[0039] In this embodiment, the opposing plate 26 of the reading glass 16, through which the document passes during scanning, is divided into two color regions in the document transport direction, i.e., the sub-scanning direction, as shown in Fig. 4. That is, the reading opposing plate 26 forms a white region 26W on the upstream side in the sub-scanning direction, that is, on the left side in Fig. 4, and a gray region 26G on the downstream side, that is, on the right side in Fig. 4. Therefore, when the document passes through the white region 26W, the background color is white, and when the document passes through the gray region 26W, the background color is gray.

[0040] An enlarged view of the structure around the opposing plate 26 is shown in Figure 5. An original (not shown) whose passing timing has been adjusted by the registration roller 50 is transported through the gap between the reading glass 16 and the opposing plate 26, and is guided by the upward inclined surface of the inclined guide 60 to be sent onto the original discharge tray 42 (Figure 3).

[0041] In this embodiment, in the case of skimming, the home position of the scanning unit 52 including the light source 53 and the mirror 54 can be switched and set to either a first position below the gray area 26G of the opposing plate 26 shown in Fig. 6 or a second position below the white area 26W shown in Fig. 7. In other words, the home position of the scanning unit 52 can be switched and set to either the first position (Fig. 6) or the second position (Fig. 7).

[0042] In this embodiment, the actual distance between the first position and the second position is, for example, 3-5 mm.

[0043] In addition, in order to switch the home position of the scanning unit 52 of the image reading unit 12 to the first position or the second position in this manner, it is only necessary to change the initial value given to the stepping motor (not shown) that controls the movement of the scanning unit 52 in the sub-scanning direction.

[0044] In this embodiment, when a mode for performing crop processing is selected by the user, the home position of the scanning unit 52 is first set to the first position (below the gray area 26G of the opposing plate 26) shown in FIG.

[0045] The cropping process is a process of cutting out the image data of the document read by the image reading unit 12 and the document image to obtain the document image in the correct orientation.

[0046] Figure 8 shows an example of successful cropping of an original image in this cropping process. In this case, the home position of scanning unit 52 is set to the first position, so the color of background 62 (background color) of original image 100A is gray. On the other hand, the ground color of the original in this case is white or has a brightness close to white. In cropping, the edges of the original image are detected based on the difference in brightness (density difference) between the color of the original image (ground color) and the background color of the original image. Therefore, when the difference in brightness between the original image and the background color is large, as in the example of Figure 8, cropping of the original image, i.e., cropping, is successful.

[0047] As in this embodiment, when the user selects the cropping mode, the home position of the scanning unit 52 is initially set to the first position, which increases the probability of successful cropping based on the fact that the color of the document is often white or a color close to white.

[0048] 9A, the brightness of the background color of the document is low, and the brightness of the document image 100A is relatively low. Meanwhile, in this case, the home position of the scanning unit 52 is also set to the first position. Therefore, the color of the background 62 (background color) is gray and has low brightness. Therefore, in the first scan, the difference in brightness between the document image 100A and the background color is small, and the document image fails to be detected. In other words, the cropping process fails.

[0049] Therefore, the image forming apparatus 10 displays an error screen 64 on the display 19 (FIG. 1) as shown in Fig. 10. This error screen 64 includes a message 66 saying "Cropping has failed," informing the user who requested cropping that the cropping has failed.

[0050] On the other hand, a message 68 "Do you want to perform cropping again?" is displayed to ask the user whether or not he or she wants to perform cropping again.

[0051] In response to the message 68, the user indicates whether or not he wishes to continue with the cropping process.

[0052] If desired, the user can touch the touch panel of the display 19 to check the check box 70Y and press the continue button 72. At this time, the document must be scanned again, so the user must return all documents to the document tray 34 (FIG. 2) in accordance with the message.

[0053] If not desired, the user touches the touch panel of the display 19 to check the check box 70N and operates the cancel button 74.

[0054] If the cancel button 74 is operated, the cropping process can be ended immediately.

[0055] When all the documents are returned to the document tray 34 and the continue button 72 is operated, the image forming apparatus 10 (or its computer) sets the home position of the scanning unit 52 to the second position for the second reading. At this time, the scanning unit 52 is positioned below the white area 26W of the reading counter plate 26. Then, the documents are read in the same way as in the first reading.

[0056] In the second scan, the scanning unit 52 is positioned below the white area 26W, so the color of the background 62 (background color) is white or close to white and has high brightness. On the other hand, the original image 100A has a relatively low brightness, as described above. As shown in FIG. 9B, when the home position of the scanning unit 52 is set to the second position, if there is a large difference in brightness between the original image and the background color, the cropping process is successful.

[0057] In a typical image forming device, the opposing plate (corresponding to the opposing plate 26) is set to a solid white color, and considering that the background color of the original is often relatively bright, such as white, the difference in brightness between the original image and the background is small, and the possibility of successfully extracting the original image is not high.

[0058] In contrast, in this embodiment, the reader counter plate 26 is divided into a relatively bright area such as the white area 26W and a relatively low-brightness area such as the gray area 26G in the sub-scanning direction of the scanning unit 52, i.e., the document transport direction in the case of flow reading, and the home position of the scanning unit 52 can be switched to a first position below the gray area 26G or a second position below the white area 26W. In the cropping process, the home position of the scanning unit 52 is first set to the first position and the document image is read. Considering that the background color of a document is often relatively bright, such as white, the brightness difference between the cropped document image 100A and the background 62 is large, increasing the likelihood of successful cropping.

[0059] When the home position of the scanning unit 52 is set to the first position and the cropping process fails, it is possible to assume that the brightness of the background color of the document is low. In this case, if the home position of the scanning unit 52 is set to the second position, the brightness difference between the document image and the background can be secured, and the cropping process is likely to be successful on the second document reading.

[0060] The image forming apparatus 10 in the embodiment shown in FIG. 1 is a multifunction peripheral, and FIG. 11 is a block diagram showing an example of the electrical configuration of this image forming apparatus 10. The image forming apparatus 10 includes an image reading unit 12, an image processing unit 28, an image forming unit 30, and a paper feeding unit 31. The image forming apparatus 10 also includes a main control unit 76 (including a main memory unit 78), an auxiliary memory unit 80, and a communication unit 82. The image forming apparatus 10 also includes an operation unit 18. These are connected to each other via a common bus 84.

[0061] As already explained, the image reading unit 12 reads an image of a document and outputs two-dimensional image data corresponding to the image of the document.

[0062] Image forming unit 38 is an image forming means that forms an image on recording paper by electrophotography. For this reason, image forming unit 30 includes a photosensitive drum, a charging device, an exposure device, a developing device, a transfer device, a fixing device, and the like, all of which are not shown. Image data used in the image formation process by image forming unit 38 includes, for example, image data output from image reading unit 12.

[0063] The paper feed unit 31 feeds recording paper one sheet at a time into the image forming unit 30.

[0064] The communication unit 82 is a communication means capable of performing two-way communication processing via a network (not shown). The communication unit 82 is also capable of performing communication via a wireless system such as Wi-Fi (registered trademark).

[0065] The main control unit 76 is a control means that performs overall control of the image forming apparatus 10. Therefore, the main control unit 76 is a CPU or processor, and together with the main storage unit 78, constitutes a computer. The main storage unit 78 includes, for example, a RAM and a ROM.

[0066] The auxiliary storage unit 80 is an auxiliary storage means including, for example, a hard disk, a flash memory, etc. Under the control of the main control unit 76, this auxiliary storage unit 80 appropriately stores various image data such as image data output from the image reading unit 36, as well as various data other than image data.

[0067] As described above, the operation unit 18 has the touch panel display 19. Furthermore, the operation unit 18 may include appropriate hardware switches such as push button switches in addition to the touch panel.

[0068] FIG. 12 is an illustrative view showing an example of a memory map of the main storage unit (RAM) 78 in the embodiment of FIG.

[0069] 12, the main storage unit 32 includes a program storage area 86 and a data storage area 88. In the program storage area 86, a control program for the image forming apparatus 10 is stored.

[0070] The control programs of the image forming apparatus 10 include a display control program 90, an operation detection program 92, an image reading program 94, an image processing program 96, an image forming program 98, a paper feeding program 100, and the like.

[0071] The display control program 90 is a program that generates the display screen data required to display various screens on the screen of the display 19 based on the display image generation data in the display image generation data memory area 102 described below, and uses that display screen data to display images on the display 19.

[0072] The operation detection program 92 is a program for detecting operation data corresponding to an operation on the operation unit 18 and storing the operation data in the operation data storage area 104 described below. For example, when a touch panel (not shown) is touched, the main control unit (computer) 76 acquires touch coordinate data output from the touch panel as operation data in accordance with the operation detection program 92 and stores the operation data in the operation data storage area 104. When a hardware button or key (not shown) provided on the operation unit 18 is pressed or operated, the main control unit 76 acquires operation data resulting from the pressing or operation of the button or key in accordance with the operation detection program 92 and stores the operation data in the operation data storage area 104.

[0073] The image reading program 94 controls the automatic document feeder 38 and the image reading unit 12 (both in FIG. 3) to read the document placed on the document tray 34 or the document table 14, and stores the data of the read document image 100A in the temporary storage data area 106 together with the background image data of the background 62 (FIGS. 8 and 9).

[0074] The image processing program 96 mainly executes preprocessing for image formation by the image forming unit 30, such as cropping of image data read in accordance with the image reading program 94. Cropping will be described with reference to the flow charts of FIGS.

[0075] The image forming program 96 is a program that controls the image forming unit 30 to print image data on recording paper supplied from the paper feed unit 31 .

[0076] The communication program 100 is a program for controlling the communication unit 82 to communicate with other image forming apparatuses, information processing apparatuses (servers), etc. via a network (not shown).

[0077] Although not shown, the program storage area 80 also stores other programs necessary for controlling the user terminal 12.

[0078] In the data storage area 88, a display image generation data storage area 102, an operation data storage area 104, a temporary storage area 108, a setting data storage area 110, and the like are set.

[0079] The display image generation data in the display image generation data storage area 102 is data including polygon data, texture data, etc. for generating a display image. The display image generation data also includes image data corresponding to software keys, image generation data for displaying each screen such as the error screen 64, etc.

[0080] The operation data in the operation data storage area 104 is operation data detected in accordance with the operation detection program 92, and is stored in chronological order. Note that the operation data is deleted after being used in processing by the main control unit 76.

[0081] The temporary storage area 108 temporarily stores image data read by the image reading unit 12, for example, for image processing by the image processing program 96, etc.

[0082] The setting data storage area 110 stores various parameters set by the user using the operation unit 18, such as copy density, enlargement / reduction, and other setting data.

[0083] Although not shown, the data storage area 82 stores other data necessary for the execution of the control program of the user terminal 12, and also includes flags and counters (timers) necessary for the execution of the control program. An example of the flag is a detection flag that indicates whether detection (extraction) of the document image during the first reading was successful or unsuccessful. When this detection flag is on, it indicates successful detection, and when it is off, it indicates unsuccessful detection.

[0084] Next, the cropping operation when there is one document will be described with reference to Fig. 13. The operation in Fig. 13 is started when the user requests cropping, so the home position of the scanning unit 52 of the image reading section 12 is set to the first position shown in Fig. 6.

[0085] In the first step S1, the main control unit 76 (FIG. 11) controls the image reading unit 12 in accordance with the image reading program 94 to read the image of the document set on the document placement tray 34 (FIG. 3). In other words, the first reading is executed. This step S1, in which the main control unit 76 controls the document reading unit 12 to read the document at the reading position P1 (FIG. 3), functions as the first reading execution unit. The image data of the document is stored in the temporary storage area 108 (FIG. 12) together with the image data of the background 62 (FIG. 8).

[0086] In the next step S3, the main control unit 76 controls the image processing unit 28 in accordance with the image processing program 96 to execute a process for detecting an original image in the image data stored in the temporary storage area 108, and determines whether the original image can be detected. If the edge of the original image can be detected, the process proceeds to the next step S5.

[0087] That is, in this step S5, the main control unit 76 controls the image processing unit 28 to execute the process of detecting the document image, so it functions as a detection unit, and also functions as a judgment unit, because it determines whether the detection unit has detected the document image.

[0088] If the answer to step S3 is "YES," it means that the difference in brightness between the original image and the background image is equal to or greater than a certain value. In this case, the main control unit 76 stores the position data of the original image, for example, the coordinate data of each position indicating the shape of the original image, in the temporary storage area 108 in step S5.

[0089] Then, in step S7, the main control unit 76 performs cropping using a known method in accordance with the position data of the document image data stored in step S5. For example, the document image is rotated so that the inclination of the document image with respect to the X-axis and Y-axis is within a predetermined angle.

[0090] If the determination in step S3 is "NO," the main control unit 76 displays the error screen 64 shown in Fig. 10 in step S9. Then, in step S11, the main control unit 76 refers to the operation data in the operation data storage area 104 to determine whether the user has operated the continue button 72.

[0091] If the result of step S11 is "NO," that is, if the user operates the cancel button 74, the cropping process ends immediately.

[0092] If the determination in step S11 is "YES", that means that the document has been returned to the document tray 34 in accordance with the error screen 64 and the continue button 72 has been operated.

[0093] Then, in step S13, the main control unit 76 sets the home position of the scanning unit 52 of the image reading unit 12 to the second position shown in FIG.

[0094] Thereafter, in step S15, similar to step S1, the image of the document set on the document tray 34 is read by the image reading unit 12. If the document image fails to be detected during the first reading ("NO" in step S3), this means that there is no significant difference in brightness between the document image 100A and the background color, as shown in FIG. 9A. In other words, this means that while the background color is gray, the document has a ground color with a brightness close to that background color. In the second reading, the background color is white, so the document image, which had no brightness difference against the gray background color, now has a brightness difference of a certain level or more against the white background color. In other words, in the second reading, the image processing unit 28 is likely to be successful in extracting the document image.

[0095] That is, the second reading is executed in step S15. This step S15 in which the main control unit 76 controls the document reading unit 12 to read the document at the reading position P1 (FIG. 3) functions as a second reading execution unit.

[0096] Then, in step S17, the main control unit 76 detects the document image based on the image data stored in the temporary storage area 108. In this step S17, as in the previous step S3, the main control unit 76 controls the image processing unit 28 to detect the document image from the image data. This step S17 functions as a detection unit.

[0097] Thereafter, in step S19, similar to step S5, the position information of the original image is stored, and in step S21, cropping is performed similar to step S7.

[0098] In this way, even if the cropping process fails in the first reading when the background color of the reading is set to gray, the probability of successful cropping can be increased by setting the background color to white in the second reading.

[0099] The operation when reading two or more originals will be described below with reference to Figures 14 and 15. The operation shown in Figures 14 and 15 is started when the user requests cropping, so the home position of the scanning unit 52 of the image reading section 12 is set to the first position shown in Figure 6.

[0100] In the first step S31, the main control unit 76 (FIG. 11) controls the image reading unit 12 in accordance with the image reading program 94 to read the image of the document set on the document placement tray 34 (FIG. 3). In other words, the first reading is executed. This step S31, in which the main control unit 76 controls the document reading unit 12 to read the document at the reading position P1 (FIG. 3), functions as the first reading execution unit. The image data of this document image is stored in the temporary storage area 108 (FIG. 12) together with the image data of the background 62 (FIG. 8).

[0101] In the next step S33, the main control unit 76 controls the image processing unit 28 in accordance with the image processing program 96 to execute a process for detecting an original image in the image data stored in the temporary storage area 108, and determines whether the original image can be detected. If the edge of the original image can be detected, the process proceeds to the next step S35.

[0102] That is, in this step S33, the main control unit 76 controls the image processing unit 28 to execute the process of detecting the document image, so that it functions as a detection unit, and also functions as a judgment unit, because it determines whether the detection unit has detected the document image.

[0103] If "YES" is determined in step S33, it means that the difference in brightness between the original image and the background image is equal to or greater than a certain value. In this case, the main control unit 76 turns on a detection flag (indicating whether the edge of the original image can be detected) in step S35, and stores the read original image data in the temporary storage area 108.

[0104] Then, in step S37, the page number information of the document is stored in the temporary storage area 108. This page number information can be counted by the automatic document feeder 38, or can be counted from the extracted document image data.

[0105] Thereafter, in steps S39 and S41, similar to the previous steps S5 and S7, the position information of each page of the document image is saved, and cropping is performed by a known method.

[0106] Then, in the next step S43, it is determined whether the cropping process has been performed up to the last page of the document placed on the document tray 34, and if "NO", the process returns to the previous step S31 and repeats the process up to step S41 in the same manner.

[0107] If the determination in step S33 is "NO," that is, if the document image cannot be detected, the detection flag is turned off in step S45, and information on the number of pages for which detection failed is stored in the temporary storage area 108 in step S47.

[0108] If the process is executed up to the last page and the result in step S43 is "YES," it is determined in the following step S49 whether or not there has been a detection failure. This can be determined by the main control unit 76 referring to the detection flag. If the result in step S49 is "YES," that is, if the detection flag is off, the process proceeds to step S53 shown in FIG. 15.

[0109] If "NO" is determined in step S49, that is, if there is no page for which detection has failed, the document images are rearranged in the order of the page information and stored in the temporary storage area 108 in step S5.

[0110] If "YES" in the step S49, an error screen 64 shown in FIG. 10 is displayed on the display 19 in a step S53.

[0111] In step S53, the error screen 64 is displayed, and in step S55, the main control unit 76 refers to the operation data in the operation data storage area 104 and determines whether the user has operated the continue button 72.

[0112] If the result of step S55 is "NO," that is, if the user operates the cancel button 74, the cropping process ends immediately.

[0113] If "YES" is determined in step S55, that means that all the documents have been returned to the document tray 34 in accordance with the error screen 64 and the continue button 72 has been operated.

[0114] Then, in step S57, the main control unit 76 sets the home position of the scanning unit 52 of the image reading unit 12 to the second position shown in FIG.

[0115] Thereafter, in step S59, similar to step S31, the image of the document set on the document tray 34 is read by the image reading unit 12. If the document image fails to be detected during the first reading ("NO" in step S33), this means that there is no significant difference in brightness between the document image 100A and the background color, as shown in FIG. 9A. In other words, this means that the background color is gray, and the document's ground color has a brightness close to that background color. In the second reading, the background color is white, so the document image, which had no brightness difference against the gray background color, now has a brightness difference of a certain level or more against the white background color. In other words, in the second reading, the image processing unit 28 is likely to be successful in extracting the document image.

[0116] That is, the second reading is executed in step S59. This step S59 in which the main control unit 76 controls the document reading unit 12 to read the document at the reading position P1 (FIG. 3) functions as a second reading execution unit.

[0117] In the next step S61, the detection flag is referenced to determine whether the first attempt to extract the document image of the page in question has failed. If the first attempt has failed, the detection flag should have been turned off. Therefore, in step S61, it is determined whether the detection flag is turned off.

[0118] Then, in step S63, the document image is detected from the document image data. That is, in step S63, the document of the page for which document detection failed during the first reading is detected. Step S63, in which the main control unit 76 controls the image processing unit 28 to detect the document image from the image data, functions as a detection unit.

[0119] Thereafter, in step S65, similar to steps S5 and S19, the position information of the original image is stored, and in step S67, similar to steps S7 and S21, cropping is performed.

[0120] If it is determined in step S69 that the cropping process has been completed up to the final page of the document, the cropping process ends.

[0121] In this way, even if the cropping process fails in the first reading when the background color of the reading is set to gray, the probability of successful cropping can be increased by setting the background color to white in the second reading.

[0122] In the above embodiment, the white area 26W and the gray area 26G are formed adjacent to each other in the document transport direction on the reading counter plate 26 in the case of skimming, thereby forming two areas with a brightness difference in the sub-scanning direction of the scanning unit 52, i.e., the document transport direction. However, the formation of two areas with such a brightness difference is not limited to a white area and a gray area. In short, it is sufficient to form a low-brightness area and a high-brightness area having a higher brightness than the low-brightness area adjacent to each other in the sub-scanning direction of the scanning unit 52 (document transport direction) on the surface of the counter plate 26 facing the reading glass 16. [Explanation of symbols]

[0123] 10...Image forming device 12...Image reading unit 16... Reading glass (light-transmitting member) 26...Reading counter plate 26W…white area 26G…gray area 28...Image processing unit 38...Automatic document feeder 52...Scanning unit 64...Error screen 72 ...Continue button 76...Main control unit 100... Manuscript P1: Reading position

Claims

1. An image forming apparatus of a flow-reading type in which an image reading unit provided at a reading position set on a conveyance path irradiates a document with light from a scanning unit to read the document, a conveying section that conveys the document along the conveying path; a light transmitting member provided below the transport path at the reading position; an opposing plate provided opposite the light transmitting member, through which the document being conveyed passes between the opposing plate and the light transmitting member, the opposing plate having a low-lightness region and a high-lightness region having a lightness higher than that of the low-lightness region formed adjacent to each other in the conveyance direction of the document on a surface opposing the light transmitting member; a first reading execution unit that sets a home position of the scanning unit to a first position corresponding to the low-lightness area and reads an original that passes the reading position by the image reading unit; a determination unit that determines whether an original image has been detected from image data obtained by the first reading execution unit; and An image forming apparatus comprising a second reading execution unit that, when the judgment unit determines that an original image cannot be detected from the image data, sets the home position of the scanning unit to a second position corresponding to the high-brightness area and reads an original passing through the reading position using the image reading unit.

2. An image forming apparatus of a flow-reading type in which an image reading unit provided at a reading position set on a conveyance path irradiates a document with light from a scanning unit to read the document, a conveying section that conveys the document along the conveying path; a light-transmitting member provided below the transport path at the reading position; and an opposing plate that is provided opposite the light transmitting member and through which the document being conveyed passes between the opposing plate and the light transmitting member, the opposing plate having a low-lightness region and a high-lightness region having a lightness higher than the low-lightness region formed adjacent to each other in a conveying direction of the document, on a surface opposing the light transmitting member; a first reading execution step of setting a home position of the scanning unit to a first position corresponding to the low-lightness area and reading an original passing through the reading position by the image reading unit; a determination step of determining whether an original image has been detected from image data obtained by the first reading in the first reading execution step; and A control method for an image forming device, comprising a second reading execution step of setting the home position of the scanning unit to a second position corresponding to the high brightness area and reading the document passing through the reading position by the image reading unit when it is determined in the judgment step that the document image cannot be detected from the image data.

3. An image forming apparatus of a flow-reading type in which an image reading unit provided at a reading position set on a conveyance path irradiates a document with light from a scanning unit to read the document, a conveying section that conveys the document along the conveying path; a light-transmitting member provided below the transport path at the reading position; and In an image forming apparatus including an opposing plate that is provided opposite the light transmitting member and through which the document being conveyed passes between the opposing plate and the light transmitting member, the opposing plate having a low-lightness region and a high-lightness region having a lightness higher than the low-lightness region formed adjacent to each other in a conveying direction of the document on a surface opposing the light transmitting member, the computer of the image forming apparatus being configured to: a first reading execution unit that sets a home position of the scanning unit to a first position corresponding to the low-lightness area and reads an original that passes the reading position by the image reading unit; a determination unit that determines whether an original image has been detected from image data obtained by the first reading execution unit; and A program for an image forming device that, when the judgment unit determines that an original image cannot be detected from the image data, sets the home position of the scanning unit to a second position corresponding to the high-brightness area and causes the image reading unit to function as a second reading execution unit that reads an original passing through the reading position.

Images