Image reading apparatus

Abstract

To suppress a possibility that an incorrect pair of a first surface image and a second surface image of a plurality of documents is identified in multi-crop processing.SOLUTION: An image reading unit 21 generates a first read image including first surface images of respective first surfaces of a plurality of documents, and a second read image including second surface images of respective second surfaces of the plurality of documents. A crop processing unit 42 extracts the first surface images and the second surface images from the first read image and the second read image by multi-crop processing, determines whether or not each of the first surface images and each of the second surface images has a rectangular shape by auto-crop processing, generates pairs of the first surface images and the second surface images when shapes of all the first surface images and shapes of all the second surface images are rectangular, and the number of the first surface images is identical to the number of the second surface images, and otherwise, does not generate the pairs of the first surface images and the second surface images and issues a warning.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an image reading device. [Background technology]

[0002] One image reading device (a) extracts first-side images from a first read image including first-side images, which are images of one side of each of a plurality of documents, using multi-crop processing; (b) extracts second-side images from a second read image including second-side images, which are images of the other side of each of the plurality of documents, using multi-crop processing; and (c) identifies pairs of first-side images and second-side images for each document (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2018 / 124146 Summary of the Invention [Problem to be solved by the invention]

[0004] However, if the above-mentioned scanned image is obtained when part of the above-mentioned document overlaps another document, the number of first-side images and second-side images extracted by the multi-crop processing may not match, and an incorrect pair may be identified.

[0005] The present invention has been made in consideration of the above-mentioned problems, and aims to provide an image reading device that reduces the possibility of identifying incorrect pairs of first-side images and second-side images of multiple documents during multi-crop processing. [Means for solving the problem]

[0006] The image reading device of the present invention includes an image reading unit that generates a first read image including a first-side image of an image on a first side of each of a plurality of documents and a second read image including a second-side image of a second side of each of the plurality of documents, a read image acquisition unit that acquires the first read image and the second read image, and (a) a multi-crop process that extracts the first-side image from the first read image and extracts the second-side image from the second read image, and (b) an auto-crop process that determines whether the shape of any of the first-side images is rectangular and whether the shape of any of the second-side images is rectangular. (c1) if the shape of any of the first-side images is rectangular, the shape of any of the second-side images is rectangular, and the number of the first-side images and the number of the second-side images are the same, a pair of the first-side images and the second-side images is generated; and (c2) if the shape of any of the first-side images is not rectangular, or the shape of any of the second-side images is not rectangular, or the number of the first-side images and the number of the second-side images are not the same, a crop processing unit is provided that issues a warning without generating a pair of the first-side images and the second-side images. [Effects of the Invention]

[0007] According to the present invention, an image reading device is provided that reduces the possibility of identifying erroneous pairs of first-side images and second-side images of multiple documents in multi-crop processing.

[0008] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a side view showing the internal configuration of an image reading device according to an embodiment of the present invention. [Figure 2] FIG. 2 is a block diagram showing the electrical configuration of the image reading apparatus shown in FIG. [Figure 3] FIG. 3 is a flowchart (1 / 2) illustrating the operation of the image reading apparatus shown in FIG. [Figure 4] FIG. 4 is a flowchart (2 / 2) illustrating the operation of the image reading apparatus shown in FIG. [Figure 5] FIG. 5 is a diagram showing an example of the first read image. [Figure 6] FIG. 6 is a diagram showing an example of the second read image. [Figure 7] FIG. 7 is a diagram showing an example of the warning screen. [Figure 8] FIG. 8 is a diagram showing another example of the first read image. [Figure 9] FIG. 9 is a diagram showing another example of the second read image. [Figure 10] FIG. 10 is a diagram showing another example of the warning screen. [Figure 11] FIG. 11 is a diagram showing yet another example of the warning screen. [Figure 12] FIG. 12 is a diagram showing yet another example of the first read image. [Figure 13] FIG. 13 is a diagram showing still another example of the second read image. [Figure 14] FIG. 14 is a diagram showing an example of a preview display. [Figure 15] FIG. 15 is a diagram illustrating a change in the combination of the first and second images in the preview display. [Figure 16] FIG. 16 is a diagram showing an example of a confirmation screen for the first read image. [Figure 17] FIG. 17 is a diagram showing still another example of the first read image and the second read image. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0011] Fig. 1 is a side view showing the internal configuration of an image reading device according to an embodiment of the present invention. The image reading device shown in Fig. 1 is a device such as a scanner, a copier, or a digital multifunction peripheral. In Fig. 1, contact glass 1 is installed on the top surface of the image reading device body and is a transparent table on which a document is placed when an image is read.

[0012] The carriage 2 is also mounted so as to be movable in the sub-scanning direction (i.e., the scanning direction) by a drive source (not shown). The carriage 2 has light sources 11 and 12 and a mirror 13. The light sources 11 and 12 are each a linear light source aligned in the main scanning direction, and emit light, for example, from a plurality of light-emitting diodes arranged along the main scanning direction. The light emitted from at least one of the light sources 11 and 12 is irradiated onto a document placed on the contact glass 1 according to the position of the carriage 2. The light irradiated onto the document is reflected by the surface of the document. The mirror 13 then reflects the light reflected from the document toward the carriage 3. The carriage 3 is also mounted so as to be movable together with the carriage 2 in the sub-scanning direction by a drive source (not shown). The carriage 3 has mirrors 14 and 15. The mirrors 14 and 15 reflect the light from the mirror 13 of the carriage 2 twice and emit it along the sub-scanning direction.

[0013] The imaging lens 4 focuses light from the mirror 15 of the carriage 3 onto the image sensor 5. The image sensor 5 is a one-dimensional image sensor having a predetermined number of light receiving elements arranged in the main scanning direction, and outputs an electrical signal for each line corresponding to the amount of light received by that number of pixels. For example, a CCD (Charge Coupled Device) is used as the image sensor 5.

[0014] An image reading unit 21 is composed of the carriages 2 and 3, the imaging lens 4, the image sensor 5, the document cover 6, the light sources 11 and 12, the mirrors 13, 14, and 15, and the like.

[0015] The image reading unit 21 has the above-described configuration and generates a read image of a predetermined size including an original image optically read from an original. For example, a read image of a size corresponding to a predetermined area on the contact glass 1 is generated, and the original image corresponding to the original on the contact glass 1 is included in the read image.

[0016] Fig. 2 is a block diagram showing the electrical configuration of the image reading device shown in Fig. 1. In addition to the image reading unit 21 described above, this image reading device includes an operation panel 31, a printing device 32, a storage device 33, a communication device 34, and a processing unit 35.

[0017] The operation panel 31 is arranged on the surface of the housing of the image reading device and includes a display device 31a such as a liquid crystal display that displays various information to the user, and an input device 31b such as hard keys or a touch panel that detects user operations.

[0018] The printing device 32 is an internal device that prints an original image or the like onto recording paper or the like using an electrophotographic method or the like.

[0019] The storage device 33 is a non-volatile storage device that stores data and programs.

[0020] The communication device 34 is a network interface or a peripheral device interface, and is a device for communicating data with external devices.

[0021] The processing unit 35 includes, for example, an ASIC (Application Specific Integrated Circuit) or a computer that operates according to a control program, and the ASIC or computer operates as a read image acquisition unit 41, a crop processing unit 42, and a data output unit 43.

[0022] The read image acquisition unit 41 acquires the read image (image data) generated by the image reading unit 21.

[0023] When a user wishes to read images of both sides of multiple rectangular documents such as ID cards, business cards, etc., the user first places the multiple documents on contact glass 1 with their first sides (here, the front sides) facing downwards, and image reading unit 21 generates first read images including first-side images that are document images of the first sides of each of the multiple documents. Next, the user places the multiple documents on contact glass 1 with their second sides (here, the back sides) facing downwards, and image reading unit 21 generates second read images including second-side images that are document images of the second sides of each of the multiple documents. Then, read image acquisition unit 41 acquires these first read images and second read images.

[0024] The crop processing unit 42 (a) extracts a first-side image from the first read image using multi-crop processing and extracts a second-side image from the second read image, and (b) performs auto-crop processing on each first-side image and auto-crop processing on each second-side image, and determines whether the shape of each of the first-side images is rectangular and whether the shape of each of the second-side images is rectangular.

[0025] In the multi-crop process, an object included in each scanned image is extracted as a first or second image. In the auto-crop process, whether the shape of the first or second image is rectangular is determined based on whether the shape of the circumscribing rectangle of each first or second image matches the shape of the object in the first or second image.

[0026] Then, if the shape of all the first-side images is rectangular, the shape of all the second-side images is rectangular, and the number of extracted rectangular-shaped first-side images is the same as the number of extracted rectangular-shaped second-side images, the crop processing unit 42 identifies corresponding first-side images and second-side images based on the position of the first-side image in the first read image and the position of the second-side image in the second read image, and generates a pair of the identified first-side images and second-side images.

[0027] On the other hand, if the shape of any of the first-side images is not rectangular, or if the shape of any of the second-side images is not rectangular, or if the number of first-side images and the number of second-side images are not the same, the crop processing unit 42 issues a warning without generating a pair of first-side images and second-side images.

[0028] This warning includes a message indicating that the first or second side image was not acquired correctly, a message urging the user to properly reposition the multiple documents on the contact glass 1 and perform rescanning, and the like.

[0029] Furthermore, in this embodiment, the crop processing unit 42 (a) generates the above-mentioned pair, displays a preview of the pair on the display device 31a, and (b) when a user operation on the preview display is detected by the input device 31b, determines whether or not to approve the pair in accordance with the user operation. If the crop processing unit 42 does not approve the pair, it discards the pair (that is, the association of the first and second images as a pair is discarded, but the first and second images themselves are not discarded).

[0030] In this embodiment, the crop processing unit 42 also changes the combination of the first and second images currently paired in the preview display of the pair in accordance with a user operation.

[0031] Furthermore, the data output unit 43 outputs image data in which the paired first and second surface images are associated with each other. For example, the data output unit 43 outputs the paired first and second surface images as a single data file.

[0032] Next, the operation of the image reading device will be described below with reference to the flowcharts shown in Figures 3 and 4.

[0033] First, the user places multiple rectangular documents, such as ID cards, business cards, etc., on the contact glass 1 with their first sides (here, the front sides) facing downwards, and when the user performs a predetermined operation, the image reading unit 21 performs an image reading operation to generate a first read image, and the read image acquisition unit 41 acquires this first read image from the image reading unit 21 (step S1).

[0034] The crop processing unit 42 performs multi-crop processing on the first scanned image to extract first-side images, and performs auto-crop processing on each extracted first-side image to determine whether the shape of each first-side image is rectangular (step S2). If it is determined that the shape of any first-side image is not rectangular, the crop processing unit 42 displays a warning screen requesting rescanning on the display device 31a (step S3). Then, the processing from step S1 onwards is executed again.

[0035] If it is determined that the shape of all the first side images is rectangular, the user places the multiple documents on the contact glass 1 with their second sides (here, the back sides) facing downwards, and when the user performs a predetermined user operation, the image reading unit 21 performs an image reading operation to generate a second read image, and the read image acquisition unit 41 acquires this second read image from the image reading unit 21 (step S4).

[0036] The crop processing unit 42 performs multi-crop processing on the second scanned image to extract second-side images, and performs auto-crop processing on each extracted second-side image to determine whether the shape of each second-side image is rectangular (step S5). If it determines that the shape of any first-side image is not rectangular, the crop processing unit 42 displays a warning screen requesting rescanning on the display device 31a (step S6). Then, the processing from step S4 onwards is executed again.

[0037] FIG. 5 is a diagram illustrating an example of a first scanned image. FIG. 6 is a diagram illustrating an example of a second scanned image. FIG. 7 is a diagram illustrating an example of a warning screen. For example, when a first scanned image 101 as shown in FIG. 5 is acquired, four first-side images 111-1 to 111-4 are extracted. On the other hand, when two documents overlap each other, a second scanned image 201 as shown in FIG. 6 is acquired, and three second-side images 211-1 to 211-3 are extracted. In this case, since the shape of the second-side image 211-1 is not rectangular, a warning screen requesting rescanning, as shown in FIG. 7, is displayed. In this case, as shown in FIG. 7, the warning screen displays a message prompting rescanning of the second side, as well as an illustration of a document for which a rectangular second-side image was not obtained in the arrangement of the second-side images in the second scanned image. Note that, although a case where a non-rectangular second-side image is acquired is described here, the same applies to a case where a non-rectangular first-side image is acquired.

[0038] When it is determined that the shapes of all the first-side images are rectangular and the shapes of all the second-side images are rectangular, the crop processing unit 42 determines whether the number of first-side images and the number of second-side images are the same (step S7).

[0039] If it is determined that the number of first-side images and the number of second-side images are not the same, the cropping processor 42 displays a warning screen requesting rescanning of the smaller number of first-side images or second-side images on the display device 31a (step S8). Thereafter, if the number of first-side images is smaller than the number of second-side images, the same processes as steps S1 to S3 are executed. On the other hand, if the number of second-side images is smaller than the number of first-side images, the same processes as steps S4 to S6 are executed.

[0040] Then, the crop processing unit 42 again determines whether the number of first-side images and the number of second-side images are the same (step S9). If it is determined again that the number of first-side images and the number of second-side images are not the same, the processing from step S1 onwards is executed again.

[0041] FIG. 8 is a diagram showing another example of the first read image. FIG. 9 is a diagram showing another example of the second read image. FIG. 10 is a diagram showing another example of the warning screen. FIG. 11 is a diagram showing yet another example of the warning screen. For example, when two documents are overlapped as shown in FIG. 8 and the shape of the first face image 311-1 corresponding to the two overlapping documents is rectangular in the first read image 301, three rectangular first face images 311-1 to 311-3 are detected. However, when four rectangular second face images 411-1 to 411-4 are properly detected from the second read image 401 as shown in FIG. 9, the number of first face images 311-1 to 311-3 (=3) and the number of second face images 411-1 to 411-4 (=4) differ from each other. Therefore, in step S8, a warning screen such as that shown in FIG. 10 is displayed, requesting the user to rescan. Furthermore, if it is determined again that the number of first-side images and the number of second-side images are not the same, a warning screen such as that shown in FIG. 11 is displayed, and the processes from step S1 onwards are executed again.

[0042] On the other hand, if it is determined in step S7 or step S9 that the number of first and second image faces is the same, the crop processing unit 42 generates pairs of first and second image faces based on the positions of the first and second image faces, and determines whether the sizes of the paired first and second image faces are the same (step S10).If it is determined that the sizes of the paired first and second image faces are the same, the crop processing unit 42 discards the pair, and the processing from step S1 onwards is executed again.

[0043] Fig. 12 is a diagram showing yet another example of the first read image. Fig. 13 is a diagram showing yet another example of the second read image. For example, as shown in Fig. 12, two documents are overlapped on the first side, and in the first read image 501, the shape of the first-side image 511-1 corresponding to the two overlapping documents is rectangular. Similarly, as shown in Fig. 13, two documents are overlapped on the second side, and in the second read image 601, the shape of the second-side image 611-1 corresponding to the two overlapping documents is rectangular. In this case, three rectangular first-side images 511-1 to 511-3 and three rectangular second-side images 611-1 to 611-3 are detected, and the numbers of both images match. Since an abnormality is not detected based on the numbers of the first-side images and the second-side images, an abnormality is detected based on the difference in their sizes (the lengths of the long and short sides), and the pairs of the first-side images 511-1 to 511-3 and the second-side images 611-1 to 611-3 are discarded.

[0044] On the other hand, if it is determined that the sizes of the paired first and second images are the same, the crop processing unit 42 displays a preview of the pair as described above (step S11), and determines whether or not a user operation to approve the displayed pair (the pair is correct) is detected (step S12).If a user operation to approve the displayed pair is detected, the data output unit 43 outputs the image data of the pair, and the processing ends.

[0045] FIG. 14 is a diagram illustrating an example of a preview display. FIG. 15 is a diagram illustrating a change in the combination of the first and second images in the preview display. FIG. 16 is a diagram illustrating an example of a confirmation screen for the first scanned image. For example, as shown in FIG. 14, the preview display screen displays the first and second images grouped by pair, each grouped separately. Then, as shown in FIG. 15, if the user determines that the pair is incorrect, the user can change the pair by dragging and moving the first or second image using a touch operation or the like. In other words, when such a user operation is detected by the input device 31b, the crop processing unit 42 updates the pair in accordance with the user operation.

[0046] Also, as shown in FIG. 14, for example, a soft key (OK key) for approving the displayed pair, a soft key for starting over, a soft key for confirming the first scan (first read image), and a soft key for confirming the second scan (first read image) are also displayed. When a user operation of pressing the OK key is detected, the image data of the pair is output and the process ends. When a user operation of pressing the soft key for confirming the first scan (first read image) is detected, a confirmation screen such as that shown in FIG. 16 is displayed. This confirmation screen displays the first read image, as well as a soft key for returning to the previous screen (FIG. 14) and a soft key for rescanning the first scan (first read image). The same applies to the confirmation screen for the second read image.

[0047] Furthermore, if a user operation to approve the displayed pair is not detected in step S11, the crop processing unit 42 monitors whether a user operation has been detected for any of the options of starting over from the beginning, rescanning only the second side, or rescanning only the first side (steps S21 to S23).

[0048] If a user operation to start over from the beginning is detected (if a soft key operation shown in FIG. 14 is detected), the processes from step S1 onwards are executed. Also, if a user operation to rescan only the second side is detected, the processes from step S4 onwards are executed. Also, if a user operation to rescan only the first side is detected (if a soft key operation shown in FIG. 16 is detected), the same processes as steps S1 to S3 (steps S24 to S26) are executed, and then the processes from step S7 onwards are executed.

[0049] 17 is a diagram showing still another example of the first scanned image and the second scanned image. For example, as shown in FIG. 17, two documents are overlapped on the first side, and in the first scanned image 701, the shape of the first-side image 711-1 corresponding to the two overlapping documents is rectangular. Similarly, two documents are overlapped on the second side, and in the second scanned image 801, the shape of the second-side image 811-1 corresponding to the two overlapping documents is rectangular. Even if the numbers of both images match and the sizes of the first-side image and the second-side image of each pair match, the user can notice the abnormality through the preview display and manually discard the pair and select rescanning.

[0050] As described above, according to the above embodiment, the image reading unit 21 generates a first read image including a first-side image of an image of the first side of each of the multiple documents, and a second read image including a second-side image of the second side of each of the multiple documents. The crop processing unit 42 (a) extracts a first-side image from the first read image and extracts a second-side image from the second read image using multi-crop processing, (b) determines whether the shapes of all the first-side images are rectangular and whether the shapes of all the second-side images are rectangular using auto-crop processing, (c1) generates a pair of first-side images and second-side images if the shapes of all the first-side images are rectangular and all the second-side images are rectangular and the number of first-side images and the number of second-side images are the same, and (c2) issues a warning without generating a pair of first-side images and second-side images if the shape of any of the first-side images is not rectangular or the shape of any of the second-side images is not rectangular, or if the number of first-side images and the number of second-side images are not the same.

[0051] This reduces the possibility that an erroneous pair of first-side images and second-side images of multiple documents will be identified in the multi-crop process.

[0052] It should be noted that various changes and modifications to the above-described embodiments will be apparent to those skilled in the art. Such changes and modifications may be made without departing from the spirit and scope of the subject matter and without diminishing its intended advantages. In other words, it is intended that such changes and modifications be included within the scope of the claims. [Industrial Applicability]

[0053] The present invention is applicable to, for example, an image reading device. [Explanation of symbols]

[0054] 21 Image reading unit 41 Read image acquisition unit 42 Crop processing section

Claims

1. an image reading unit that generates a first read image including a first-side image of an image on a first side of each of a plurality of documents and a second read image including a second-side image of a second side of each of the plurality of documents; a read image acquisition unit that acquires the first read image and the second read image; (a) extracting the first-side images from the first read image and extracting the second-side images from the second read image by multi-crop processing; (b) determining whether or not the shapes of all of the first-side images are rectangular and whether or not the shapes of all of the second-side images are rectangular by auto-crop processing; (c1) generating pairs of the first-side images and the second-side images when the shapes of all of the first-side images are rectangular and the shapes of all of the second-side images are rectangular and the number of the first-side images and the number of the second-side images are the same; (c2) issuing a warning without generating pairs of the first-side images and the second-side images when the shape of any of the first-side images is not rectangular or the shape of any of the second-side images is not rectangular, or when the number of the first-side images and the number of the second-side images are not the same; An image reading device comprising:

2. The image reading device according to claim 1, characterized in that the crop processing unit (a) displays a preview of the pair when the pair is generated, (b) determines whether or not to approve the pair in accordance with a user operation on the preview display, and (c) discards the pair if the pair is not approved.

3. 3. The image reading device according to claim 2, wherein the crop processing unit changes the combination of the first image and the second image that are currently in the pair in accordance with a user operation in the preview display of the pair.

Images