JP6683017B2 - Image processing apparatus, image processing system, image processing method, and program - Google Patents

Description

  The present invention relates to an image processing device, an image processing system, an image processing method, and a program.

  In an image reading device such as a non-contact scanner device, shading correction is performed on a read image in order to reduce the influence of unevenness in the amount of light that occurs due to the light environment of the installation location.

  Shading correction is, for example, detecting the brightness unevenness of the entire read image by reading in advance a white reference medium whose in-plane reflectance is substantially uniform, and correcting the brightness of the entire read image based on the detected brightness unevenness. To do.

  Here, if dust or dirt is attached to the reference medium used for shading correction, the dust or dirt becomes an abnormal point, so an image of the reference medium with dust or the like (hereinafter also referred to as a medium image) is used. It was difficult to accurately and accurately perform shading correction.

  Therefore, for example, in Patent Document 1 below, in the shading data obtained by reading the white reference plate, with respect to the processed pixel whose brightness is darker than the average value of the surrounding pixels, according to the darkness ratio of the processed pixel, A technique for performing correction based on the brightness of surrounding pixels is disclosed.

  Further, in Patent Document 2 below, in order to reduce the influence of dust adhering to the optical mirror of the scanner device, a plurality of white reference images are acquired while displacing the optical mirror, and the average of the acquired white reference images is taken. Thus, a technique for obtaining a white reference image for shading correction is disclosed.

JP, 2005-103883, A JP 2006-270603 A

  However, in the technique disclosed in the above-mentioned Patent Document 1, when dust or the like is present in a region where the light amount unevenness is superimposed, only the influence of the dust or the like is eliminated to accurately reflect the light amount unevenness. Obtaining a media image was difficult. Further, with the technique disclosed in Patent Document 2 described above, when the movement of dust or the like due to the displacement of the optical mirror is small, it is difficult to obtain an accurate medium image in which the influence of dust or the like is eliminated.

  That is, with respect to the medium image obtained by reading the reference medium, it is difficult to obtain an accurate medium image in which the influence of dust or the like is eliminated only by performing interpolation from peripheral pixels or averaging a plurality of images. More drastic measures were required.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to obtain a more accurate medium image for shading correction by eliminating the influence of dust and the like. Another object of the present invention is to provide an improved image processing device, image processing system, image processing method, and program.

In order to solve the above problems, according to an aspect of the present invention, a first medium image obtained by reading a placed reference medium, and the reference medium placed in a state different from the first medium image. An image acquisition unit that acquires the second medium image that has been read, an abnormal point detection unit that detects an abnormal point from the first medium image, and an area including the abnormal point of the first medium image, An image generation unit that generates a correction image by replacing the area including the abnormal point with the area of the second medium image that corresponds to the area, and the second medium image is included in the first medium image. There is provided an image processing apparatus which is an image obtained by reading the reference medium placed upside down with respect to the placed state .

  The image generation unit may replace an area including the abnormal point of the first medium image with an area having the same position coordinates of the second medium image.

  The area of the second medium image used for the replacement by the image generation unit may not include the abnormal point detected by the abnormal point detection unit.

  The second medium image may be an image obtained by reading the reference medium placed by moving in the horizontal direction with respect to the placed state in the first medium image.

  The second medium image may be an image obtained by reading the reference medium that is rotated and placed with respect to the placed state in the first medium image.

  The image acquisition unit may acquire the second medium image only when the abnormal point detection unit detects an abnormal point from the first medium image.

  The image processing apparatus, when an abnormal point is detected from the first medium image by the abnormal point detection unit, places the reference medium on a user in a state different from that of the first medium image. A display generation unit that generates a display instructing may be further provided.

  The correction image may be an image used for shading correction of a non-contact scanner.

  The image processing apparatus may further include the non-contact scanner.

In order to solve the above-mentioned problems, according to another aspect of the present invention, the first medium image obtained by reading the placed reference medium is placed in a state different from the first medium image. An image acquisition unit that acquires a second medium image obtained by reading the reference medium, an abnormal point detection unit that detects an abnormal point from the first medium image, and an abnormal point of the first medium image are included. An image generation unit that replaces the area with an area of the second medium image corresponding to the area including the abnormal point, and generates an image for correction, wherein the second medium image is the first medium. There is provided an image processing system which is an image obtained by reading the reference medium placed upside down with respect to the placement state in the image .

In order to solve the above-mentioned problems, according to another aspect of the present invention, the first medium image obtained by reading the placed reference medium is placed in a state different from the first medium image. Acquiring a second medium image obtained by reading the reference medium; detecting an abnormal point from the first medium image; and including the abnormal point of the first medium image by an arithmetic processing unit. Replacing the area with an area of the second medium image corresponding to the area including the abnormal point to generate a correction image, the second medium image being in the first medium image. There is provided an image processing method , which is an image obtained by reading the reference medium placed upside down with respect to the placed state .

Further, in order to solve the above-mentioned problems, according to another aspect of the present invention, a first medium image obtained by reading a reference medium on which a computer is placed and a first medium image placed in a different state from the first medium image are placed. An image acquisition unit that acquires a second medium image obtained by reading the reference medium that has been read, an abnormal point detection unit that detects an abnormal point from the first medium image, and the abnormal point of the first medium image Replacing the area containing the abnormal area with the area of the second medium image corresponding to the area containing the abnormal point, and causing the second medium image to function as an image generating unit that generates a correction image . There is provided a program , which is an image obtained by reading the reference medium that has been placed upside down with respect to the placement state in one medium image .

  As described above, according to the present invention, it is possible to obtain a more accurate medium image for shading correction in which the influence of dust or the like attached to the reference medium is eliminated.

FIG. 3 is a block diagram illustrating a functional configuration of the image reading device. FIG. 3 is a block diagram showing a functional configuration of an image processing apparatus according to an embodiment of the present invention. FIG. 3 is a schematic diagram showing a reference medium with dust and the like attached. It is a schematic diagram for demonstrating the reference | standard medium mounted in a different state. It is a flowchart figure explaining the 1st operation example of an image processing apparatus. FIG. 8 is an explanatory diagram showing an example of a display requesting the user to mount the reference medium in different states in the first operation example. It is a flowchart figure explaining the 2nd operation example of an image processing apparatus. FIG. 16 is an explanatory diagram showing an example of a display requesting the user to mount the reference medium in different states in the second operation example. FIG. 3 is a block diagram showing an example of a hardware configuration of the image processing apparatus according to the same embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and the drawings, constituent elements having substantially the same functional configuration are designated by the same reference numerals, and duplicate description will be omitted.

<1. Image reading device configuration>
First, the configuration of an image reading apparatus including an image processing apparatus according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram illustrating the functional configuration of the image reading apparatus 1.

  The image reading device 1 is, for example, a non-contact scanner device. In such an image reading device 1, uneven brightness may occur in the read image due to the illumination and shadow of the installation place. Therefore, in the image reading device 1 such as a non-contact scanner device, when the image reading device 1 is installed or before the image is read, a shading correction image indicating uneven brightness in the read image is generated, and based on the shading correction image. Thus, the brightness distribution of the read image is corrected.

  As shown in FIG. 1, the image reading device 1 includes a correction image generation unit 10, a correction image storage unit 12, a shading correction unit 11, a read image acquisition unit 13, and a display unit 14, and reads the image. It is connected to the section 2.

  The reading unit 2 optically reads the paper-like form 3 to generate a read image in which the form 3 is expressed in color or monochrome. The reading unit 2 may be composed of, for example, an image scanner or the like.

  The shading correction unit 11 performs shading correction on the read image read by the reading unit 2 based on the brightness distribution of the shading correction image stored in the correction image storage unit 12. Shading correction means obtaining a read image with less uneven brightness by correcting the brightness distribution of the read image as described above. Specifically, the shading correction unit 11 determines that the read image has brightness unevenness similar to that of the shading correction image, and corrects the brightness distribution of the shading correction image into a uniform brightness distribution. Is performed on the read image. The shading correction unit 11 may be configured by, for example, an arithmetic processing device such as an MPU (Micro Processing Unit).

  For example, the shading correction unit 11 refers to the brightness of the pixel at the corresponding position of the shading correction image for each pixel of the read image, and obtains a coefficient such that the brightness value of the pixel of the shading correction image becomes a predetermined value. Then, the brightness value of the read image may be corrected by the coefficient. More specifically, the shading correction unit 11 may calculate the difference between the brightness of the pixel of the image for shading correction and a predetermined value, and add the calculated difference to the brightness value of the pixel of the read image. Alternatively, the shading correction unit 11 may calculate the ratio of the brightness of the pixel of the shading correction image to a predetermined value and multiply the calculated ratio by the brightness value of the pixel of the read image. Note that the shading correction unit 11 may store the previously calculated difference or ratio as shading correction information and refer to the difference or ratio at the time of correction, instead of directly referring to the image for shading correction at the time of correction. .

  The correction image generation unit 10 generates a shading correction image used by the shading correction unit 11. Specifically, the correction image generation unit 10 performs the shading correction based on a medium image obtained by reading a reference medium having substantially uniform in-plane reflectance and an achromatic color (for example, white) on the entire surface. Generate an image. For example, the correction image generation unit 10 may generate the shading correction image by deleting an abnormal point due to dust or dirt adhering to the reference medium from the medium image obtained by reading the white reference medium.

  The shading correction image is an image showing uneven brightness in the read image. Therefore, it is preferable that the reference medium that is the basis of the image for shading correction has a substantially uniform in-plane reflectance so as to easily reflect the uneven brightness due to the surrounding environment such as illumination or shadow. Further, it is preferable that the entire surface of the reference medium is an achromatic color such as white so that the brightness can be easily grasped.

  The correction image storage unit 12 stores the shading correction image generated by the correction image generation unit 10. The correction image storage unit 12 may be configured by a volatile memory such as a RAM (Random Access Memory) that temporarily stores information, and may be a nonvolatile memory such as a flash memory or a storage such as an HDD (Hard Disk Drive) device. It may be configured by a device.

  The read image acquisition unit 13 acquires the read image whose brightness distribution has been corrected by the shading correction unit 11. In addition, the acquired read image may be output to an external device (for example, an image recognition device or the like) connected to the image reading device 1 or the display unit 14. According to this, since the image reading device 1 can acquire the content of the paper-like form 3 as image data, the information entered by the customer on the form 3 can be easily recognized by the image recognition device or the like. become. The read image acquisition unit 13 may be configured by an arithmetic processing device such as an MPU, for example.

  The display unit 14 is a display device that displays a read image or various information. The display unit 14 may be configured by, for example, a CRT (Cathode Ray Tube) display device, a liquid crystal display device, an organic EL (Organic ElectroLuminescence) display device, a plasma display device, or the like.

  Here, the image processing apparatus according to the present embodiment corresponds to the correction image generation unit 10 in the above configuration, and is an information processing apparatus that generates a shading correction image from a read image. The image processing apparatus according to the present embodiment eliminates abnormal points caused by dust or dirt adhering to the reference medium from the medium image, and thereby a shading correction image that more accurately reflects uneven brightness caused by the surrounding environment. Can be generated. Therefore, according to the present embodiment, the image reading device 1 can perform more accurate shading correction.

<2. Configuration of image processing device>
Next, the configuration of the image processing apparatus according to this embodiment will be described with reference to FIG. FIG. 2 is a block diagram showing the functional arrangement of the image processing apparatus 100 according to this embodiment.

  As shown in FIG. 2, the image processing apparatus 100 includes an image acquisition unit 101, a first image storage unit 102, a second image storage unit 103, an abnormal point detection unit 104, and an image generation unit 105. .

  As described above, the image processing apparatus 100 according to this embodiment corresponds to the correction image generation unit 10 in FIG. However, the shading correction unit 11, the correction image storage unit 12, the read image acquisition unit 13, and the display unit 14 may be provided in the same device as the image processing device 100, and are separate from the image processing device 100. May be provided in the device. Similarly, the reading unit 2 may be included in the same device as the image processing device 100 or may be included in a device separate from the image processing device 100.

  The image acquisition unit 101 acquires the first medium image and the second medium image from the reading unit 2. Specifically, the image acquisition unit 101 acquires the first medium image and the second medium image obtained by reading the reference medium placed on the reading table on which the form 3 is placed by the reading unit 2. . The reference medium is, for example, a piece of paper having an in-plane reflectance that is substantially uniform and having an achromatic color over the entire surface. Specifically, the reference medium may be a form whose entire surface is white.

  Here, the image processing apparatus 100 uses a plurality of medium images obtained by reading the reference mediums placed in different states to erase an abnormal point caused by dust or the like attached to the reference medium from the medium image to obtain brightness. It is possible to obtain a medium image for shading correction that reflects the unevenness more accurately (hereinafter, also simply referred to as an image for shading correction).

  This point will be specifically described with reference to FIGS. 3 and 4. FIG. 3 is a schematic diagram showing a reference medium on which dust or the like is attached, and FIG. 4 is a schematic diagram for explaining the reference medium placed in a different state.

  As shown in FIG. 3, the reference medium 30 preferably has a substantially uniform in-plane reflectance and an achromatic color such as white on the entire surface. However, dust 31 may adhere to the reference medium 30 depending on the aged use or storage environment. I have something to do. In such a case, since the dust 31, the reflectance, the saturation, the brightness, or the like changes depending on the dust 31, the abnormal point does not accurately reflect the uneven brightness. When shading correction is performed using the shading correction image generated by reading the reference medium 30 as described above, a portion to which the dust 31 is attached is treated as being darker than the actual light amount, and therefore, is smaller than the actual light amount. It will be corrected brightly. Therefore, the shading correction image generated by reading the reference medium 30 to which the dust 31 is attached does not accurately reflect the uneven brightness due to the uneven light amount of the surrounding environment.

  Therefore, in the image processing apparatus 100 according to the present embodiment, as shown in FIG. 4, the first medium image and the second medium image obtained by respectively reading the reference mediums 30A and 30B placed on the reading table 300 in different states. An image for shading correction is generated using the medium image of.

  Specifically, for the first medium image obtained by reading the reference medium 30A and the second medium image obtained by reading the reference medium 30B placed in a state different from the reference medium 30A, dusts 31A and The position coordinates of 31B are different. Therefore, the dust 31A exists in the area 32A of the first medium image, but the dust 31B does not exist in the area 32B of the second medium image having the same position coordinates in the area 32A and the medium image. Therefore, by replacing the area 32A of the first medium image with the area 32B of the second medium image, it becomes possible to erase the abnormal point caused by the dust 31A from the first medium image.

  In this way, the image processing apparatus 100 uses the first medium image and the second medium image on which the reference medium is placed in different states, and combines the areas in which there is no dust or the like to remove dust or the like. It is possible to generate an image for shading correction in which the resulting abnormal point is deleted.

  In addition, since the first medium image and the second medium image are respectively read by the reading unit 2, the reading unevenness caused by the optical system of the reading unit 2 and the surroundings of the reading unit 2 and the reading table 300 are performed. The image reflects the uneven light amount due to the environment. Therefore, the image processing apparatus 100 maintains the brightness unevenness caused by the reading unit 2 and the surrounding environment by generating the shading correction image by using the first medium image and the second medium image as described above. At the same time, it is possible to erase only the abnormal points caused by dust and the like.

  The image processing apparatus 100 may generate a shading correction image in which a part of the first medium image (that is, a portion where the dust 31 is attached) is replaced with the second medium image, but the first medium image is generated. The shading correction information may be generated using the medium image and the second medium image. In such a case, the image processing apparatus 100 does not need to generate the image itself that is a combination of the first medium image and the second medium image, and only the area including the abnormal point due to dust or the like is used for the second medium. The shading correction information may be generated by referring to the image.

  Here, the first medium image and the second medium image need only have different states of the reference medium placed on the reading table 300, and the placement state of the reference medium is not particularly limited.

  For example, as shown in FIG. 4, the second medium image may be an image obtained by reading the reference medium 30B that is placed by moving in the horizontal direction with respect to the placement state of the first medium image. Good. By moving the reference medium 30A in the first medium image horizontally in any direction in the plane, the position of the dust 31B in the medium image changes from the position of the dust 31A in the second medium image. Therefore, by combining the first medium image and the second medium image, it becomes possible to generate a shading correction image in which an abnormal point caused by dust or the like is erased.

  The amount of movement from the reference medium 30A to the reference medium 30B is arbitrary, as long as the positions of the dust particles 31A and 31B do not overlap between the first medium image and the second medium image. Good. Further, the movement from the reference medium 30A to the reference medium 30B does not necessarily need to be accurately translated in parallel unless the positions of the dusts 31A and 31B overlap. Further, on the reading table 300 on which the reference media 30A and 30B are placed, marks or protrusions 35A indicating the respective placement positions of the reference media 30A and 30B when reading the first medium image and the second medium image. And 35B may be provided.

  In addition, the second medium image may be an image obtained by reading the reference medium placed by rotating around the center of gravity of the reference medium with respect to the placed state in the first medium image. By rotating the reference medium in the first medium image in the plane, the position of dust or the like in the medium image changes from the first medium image in the second medium image. Therefore, by combining the first medium image and the second medium image, it becomes possible to generate a shading correction image in which an abnormal point caused by dust or the like is erased. The center of rotation of the reference medium does not necessarily have to be the center of gravity of the reference medium, and may be rotated about any point as long as the positions of the dust particles 31A and 31B do not overlap.

  The rotation amount of the reference medium between the first medium image and the second medium image is arbitrary, and the position of dust or the like overlaps between the first medium image and the second medium image. The rotation amount may not be so large. However, the rotation amount of the reference medium between the first medium image and the second medium image is preferably a rotation amount in which the reference media overlap with each other before and after the rotation (that is, a rotation amount having rotational symmetry). . For example, when the reference medium has a rectangular shape, the rotation amount is preferably 180 degrees, and when the reference medium has a square shape, the rotation amount may be 90 degrees, 180 degrees, or 270 degrees. preferable. In such a case, since it is not necessary to provide a plurality of marks or protrusions indicating the placement position of the reference medium when reading the medium image on the reading table 300, it is possible to further simplify the configuration of the reading table 300.

  Further, the second medium image may be an image obtained by reading the reference medium placed with the front and back surfaces reversed with respect to the placed state in the first medium image. By inverting the front and back surfaces of the reference medium in the first medium image, the positions of dust and the like in the medium image in the second medium image differ from those in the first medium image. Therefore, by combining the first medium image and the second medium image, it becomes possible to generate a shading correction image in which an abnormal point caused by dust or the like is erased. In such a case, since it is not necessary to provide a plurality of marks or protrusions indicating the placement position of the reference medium when reading the medium image on the reading table 300, it is possible to further simplify the configuration of the reading table 300.

  Here, the second medium image may be an image obtained by reading the reference medium placed by combining the above-described placement states with the first medium image. For example, the second medium image may be an image obtained by reading a reference medium that is rotated in parallel with the first medium image and is rotated. The image may be an image obtained by reading the inverted reference medium, or may be an image obtained by inverting the front surface of the first medium image and then performing parallel movement on the reference medium.

  The loading state of the reference medium between the first medium image and the second medium image may be changed by automatically moving the reading table on which the reference medium is placed. May be done by. When the loading state of the reference medium is changed by the user, the image processing apparatus 100 may present, to the user, a display requesting that the loading state of the reference medium be changed.

  The first image storage unit 102 and the second image storage unit 103 temporarily store the first medium image and the second medium image acquired by the image acquisition unit 101, respectively. For example, the first image storage unit 102 and the second image storage unit 103 may be configured by a volatile RAM or the like, or a nonvolatile flash memory or the like.

  The abnormal point detection unit 104 detects an abnormal point caused by dust or the like attached to the reference medium from the first medium image. Here, the abnormal point is an area where the luminance is extremely lower than the luminance variation due to the unevenness of the light amount due to dust adhering to the reference medium (also called a low luminance abnormal point), and the extremely high luminance. It refers to both the area (also called the high brightness abnormal point).

  Specifically, the abnormal point detection unit 104 may compare the first medium image and the second medium image, and detect an area in which the difference between the brightnesses of the first medium image and the second medium image is a threshold value or more as an abnormal point. In such a case, the abnormal point detection unit 104 can simultaneously detect both the low-luminance abnormal point and the high-luminance abnormal point with one threshold value.

  Further, the abnormal point detection unit 104 detects, in the first medium image, an area having a lower brightness than the first threshold set on the low brightness side as a low brightness abnormal point, and sets the second brightness set on the high brightness side. A region having a brightness higher than the threshold may be detected as a high brightness abnormal point. In such a case, the abnormal point detection unit 104 uses the first threshold value for detecting the low-luminance abnormal point and the second threshold value for detecting the high-luminance abnormal point, and thereby the second medium image. It is possible to detect the abnormal point from only the first medium image without acquiring.

  The image generation unit 105 replaces the area including the abnormal point of the first medium image with the area of the second medium image corresponding to the area including the abnormal point to generate the shading correction image. Specifically, the image generation unit 105 sets the area including the abnormal point detected by the abnormal point detection unit 104 in the first medium image to the area having the same position coordinate in the medium image of the second medium image. replace. As a result, the image generation unit 105 can erase an abnormal point caused by dust or the like from the first medium image and generate a shading correction image that accurately reflects the uneven brightness. The shading correction image generated by the image generation unit 105 is stored in the correction image storage unit 12 and is used as a reference for uneven brightness when shading correction is performed on the form 3 read by the reading unit 2.

  Here, the image generation unit 105 may set an area including the abnormal point with the falling edge and the rising edge of the brightness peak of the abnormal point detected by the abnormal point detecting unit 104 as boundaries. In addition, the image generation unit 105 adds an area outside the brightness peak to the area bounded by the falling edge and the rising edge of the brightness peak of the abnormal point detected by the abnormal point detection unit 104 in a predetermined range. , May be set as an area including an abnormal point. By adding an area outside the fall and rise of the brightness peak to the area including the abnormal point, the image generation unit 105 can more reliably erase the abnormal point caused by dust or the like from the first medium image. You can

  When the abnormal point detection unit 104 detects a plurality of abnormal points in the first medium image, the image generation unit 105 causes the corresponding second medium image to correspond to all the regions including the detected abnormal points. Replace with the area of.

  With the above-described configuration, the image processing apparatus 100 according to the present embodiment can generate a shading correction image that more accurately reflects uneven brightness. According to this, the image reading device 1 including the image processing device 100 according to the present embodiment can perform more accurate shading correction on the read image.

  A part of the configuration of the image processing apparatus 100 described above may be provided in a separate device connected to the image processing apparatus 100. In such a case, the image processing apparatus 100 constitutes an image processing system together with a connected separate device.

<3. Operation of image processing device>
Next, the operation of the image processing apparatus 100 according to this embodiment will be described with reference to FIGS.

[3.1. First operation example]
First, a first operation example of the image processing apparatus 100 will be described with reference to FIGS. 5 and 6. FIG. 5 is a flowchart illustrating a first operation example of the image processing apparatus 100. FIG. 6 is an explanatory diagram showing an example of a display requesting the user to mount the reference medium in different states.

  In the first operation example, after acquiring the first medium image and the second medium image, an abnormal point is detected from the first medium image, and the abnormal point is detected from the first medium image using the second medium image. It is an operation example of generating a shading correction image by deleting the abnormal point.

  As shown in FIG. 5, first, the image acquisition unit 101 acquires a first medium image (S101) and stores it in the first image storage unit 102. After that, the image acquisition unit 101 then acquires the second medium image (S103) and stores it in the second image storage unit 103.

  Here, after acquiring the first medium image, the image processing apparatus 100 requests the user to place the reference medium in a different mounting state by presenting the display as shown in FIG. 6 to the user. May be.

  For example, in the display 401 shown in FIG. 6, a message 411 requesting to change the reference medium to a different mounting state, “Please shift the reference medium and re-install, and press the confirmation button”, along with a message 411 An image 421 showing what kind of placement state is changed is shown. The user who visually recognizes such a display 401 changes the placement state of the reference medium according to the image 421, and then presses the confirmation button 431, whereby the image acquisition unit 101 causes the first medium image and the reference medium to be placed. It is possible to acquire the second medium images in different states.

  Subsequently, after acquiring the first medium image and the second medium image, the abnormal point detection unit 104 detects an abnormal point due to dust or the like from the first medium image (S105). Next, the image generation unit 105 replaces the area of the first medium image including the detected abnormal point with the corresponding area of the second medium image, so that the first medium including no abnormal point is included. An image is generated (S107). Further, the image generation unit 105 stores the first medium image, in which the region including the abnormal point is replaced, as the shading correction image in the correction image storage unit 12.

  According to the above-described operation, the image processing apparatus 100 can generate a shading correction image that more accurately reflects the uneven brightness. According to the first operation example, since the image processing apparatus 100 can be operated in the same flow regardless of whether or not an abnormal point is detected in the first medium image, exception processing does not occur. The image processing apparatus 100 can be operated in this flow.

[3.2. Second operation example]
Subsequently, a second operation example of the image processing apparatus 100 will be described with reference to FIGS. 7 and 8. FIG. 7 is a flowchart illustrating a second operation example of the image processing apparatus 100. FIG. 8 is an explanatory diagram showing an example of a display requesting the user to place the reference medium in different states.

  In the second operation example, after acquiring the first medium image, the abnormal point is detected from the first medium image, and the second medium image is detected only when the abnormal point is detected from the first medium image. It is an operation example to acquire. Therefore, in the second operation example, only when an abnormal point is detected from the first medium image, the second medium image is acquired, and the second medium image is used to correct the shading correction from the first medium image. Generate an image. When no abnormal point is detected from the first medium image, in the second operation example, the first medium image is used as the shading correction image.

  As shown in FIG. 7, first, the image acquisition unit 101 acquires the first medium image (S111) and stores it in the first image storage unit 102. After that, the abnormal point detection unit 104 detects an abnormal point caused by dust or the like from the first medium image (S113). Here, the image acquisition unit 101 determines whether or not an abnormal point is detected from the first medium image (S115), and when an abnormal point is detected (S115 / Yes), acquires the second medium image. Yes (S117).

  Here, when an abnormal point is detected from the first medium image, the image processing apparatus 100 presents a display as shown in FIG. 8 to the user, thereby making it possible for the user to place the reference medium in a different mounting state. You may ask for.

  For example, in the display 402 shown in FIG. 8, a reference medium such as "The dust has been detected from the reference medium" and the reference medium "Please move the reference medium and reinstall it and press the confirmation button" are displayed differently. A message 412 is shown requesting a change to the open state. Further, in the display 402, an image 422 showing what kind of mounting state of the reference medium is changed is shown. The user who visually recognizes such a display 402 changes the placement state of the reference medium according to the image 422 and then presses the confirmation button 432, whereby the image acquisition unit 101 causes the first medium image and the reference medium to be placed. It is possible to acquire the second medium images in different states.

  After acquiring the second medium image, the image generation unit 105 replaces the area of the first medium image including the detected abnormal point with the corresponding area of the second medium image, so that the abnormal point is detected. A first medium image that is not included is generated (S119). Further, the image generation unit 105 stores the first medium image, in which the region including the abnormal point is replaced, as the shading correction image in the correction image storage unit 12.

  It should be noted that the abnormal point detection unit 104 performs a process of detecting an abnormal point also in the second medium image, and in the second medium image, the abnormal point is located at the position where the abnormal point occurs in the first medium image. May be confirmed not to be detected. At this time, when an abnormal point is also detected in the second medium image at the position where the abnormal point occurs in the first medium image, the image processing apparatus 100 repeats the process of acquiring the second medium image. The user may be asked to re-execute the operation of re-installing the reference medium.

  On the other hand, when no abnormal point is detected (S115 / No), the image acquisition unit 101 does not acquire the second medium image, and the image generation unit 105 determines the first medium image as the shading correction image. The image is stored in the correction image storage unit 12 (S121).

  According to the above-described operation, the image processing apparatus 100 can generate a shading correction image that more accurately reflects the uneven brightness. Further, in the second operation example, the second medium image is acquired only when the abnormal point is detected in the first medium image. Therefore, the shading correction is performed when the abnormal point is not detected in the first medium image. It is possible to reduce the time required to generate the usage image.

<4. Hardware configuration of image processing device>
Next, with reference to FIG. 9, a hardware configuration of the image processing apparatus 100 according to the present embodiment will be described. FIG. 9 is a block diagram showing an example of the hardware configuration of the image processing apparatus 100 according to this embodiment.

  The information processing performed by the image processing apparatus 100 according to this embodiment is realized by cooperation between software and hardware described below.

  As illustrated in FIG. 9, the image processing apparatus 100 includes a CPU (Central Processing Unit) 151, a ROM (Read Only Memory) 153, a RAM 155, an internal bus 157, an input / output interface 159, a display unit 161, and An input unit 163, an audio output unit 165, an HDD 167, a drive 169, a network interface 171, and an external interface 173 are provided.

  The CPU 151 functions as an arithmetic processing unit and a control unit, and controls the overall operation of each component of the image processing apparatus 100 according to various programs. The CPU 151 corresponds to, for example, the image acquisition unit 101, the abnormal point detection unit 104, and the image generation unit 105, and realizes the function of each unit.

  The ROM 153 stores programs used by the CPU 151, calculation parameters, and the like. The RAM 155 temporarily stores a program used in the execution of the CPU 151, a parameter that appropriately changes in the execution, and the like. The RAM 155 corresponds to, for example, the first image storage unit 102 and the second image storage unit 103, and realizes the function of each unit.

  Further, the CPU 151, the ROM 153, and the RAM 155 are mutually connected by an internal bus 157, and further, via an input / output interface 159, a display unit 161, an input unit 163, an audio output unit 165, a HDD 167, a drive 169, and a network interface 171 described later. , And the external interface 173.

  The display unit 161 is, for example, a display device such as a CRT display device, a liquid crystal display device, an organic EL display device, and a plasma display device, and converts video data into a video and outputs the video.

  The input unit 163 is, for example, an input device for a user to input information such as a mouse, a keyboard, a touch panel, a button, a microphone, a switch and a lever, and an input that generates an input signal based on the input by the user and outputs the input signal to the CPU 151. It is composed of a control circuit.

  The voice output unit 165 is, for example, a voice output device such as a speaker and a headphone, and converts voice data and the like into voice and outputs the voice.

  The HDD 167 is a data storage device configured as an example of a storage unit of the image processing apparatus 100. The HDD 167 includes, for example, a storage medium, a recording device that records data in the storage medium, a reading device that reads data from the storage medium, and a deleting device that deletes the data stored in the storage medium.

  The drive 169 is a reader / writer for a storage medium, and is built in or externally attached to the image processing apparatus 100. The drive 169 reads information stored in a removable storage medium such as a mounted magnetic disk, optical disk, magneto-optical disk, or semiconductor memory, and outputs it to the RAM 155. The drive 169 can also write information to a removable storage medium.

  The network interface 171 is, for example, a communication interface including a communication device or the like for connecting to a communication network such as the Internet. Further, the network interface 171 may be a wired LAN (Local Area Network) or wireless LAN compatible communication device, or may be a wire communication device that performs wired communication.

  The external interface 173 is, for example, a connection port for connecting an external connection device such as a USB (Universal Serial Bus) port, an IEEE 1394 port, a SCSI (Small Computer System Interface) port, an RS-232C port, or an optical audio terminal. It is a connection interface composed of.

  As another embodiment of the present invention, the hardware such as the CPU 151, the ROM 153, and the RAM 155 built in the image processing apparatus 100 according to the embodiment of the present invention is equivalent to each component of the image processing apparatus 100. It is also possible to create a computer program that exercises the functions. A storage medium storing the computer program is also provided as another embodiment of the present invention.

<5. Summary>
As described above, according to the image processing apparatus 100 according to the embodiment of the present invention, the first medium image and the reference medium placed in a state different from the first medium image are read. By using the second medium image, it is possible to generate a shading correction image that more accurately reflects the uneven brightness. Specifically, the image processing apparatus 100 replaces the area including the abnormal point due to dust or the like of the first medium image with the corresponding area of the second medium image to remove dust from the first medium image. It is possible to eliminate only the effect of

  The preferred embodiments of the present invention have been described above in detail with reference to the accompanying drawings, but the present invention is not limited to these examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1 image reading device 2 reading unit 3 form 10 correction image generation unit 11 shading correction unit 12 correction image storage unit 13 read image acquisition unit 14 display unit 100 image processing device 101 image acquisition unit 102 first image storage unit 103 second Image storage unit 104 Abnormal point detection unit 105 Image generation unit

Claims (12)

An image acquisition unit that acquires a first medium image obtained by reading the placed reference medium and a second medium image obtained by reading the reference medium placed in a state different from the first medium image,
An abnormal point detection unit that detects an abnormal point from the first medium image;
An image generation unit that replaces a region including the abnormal point of the first medium image with a region of the second medium image corresponding to the region including the abnormal point, and generates a correction image,
Equipped with
The image processing apparatus , wherein the second medium image is an image obtained by reading the reference medium that is placed upside down with respect to the placement state in the first medium image .   The image processing device according to claim 1, wherein the image generation unit replaces an area including the abnormal point of the first medium image with an area having the same position coordinates of the second medium image.   The image processing apparatus according to claim 1, wherein the area of the second medium image used for replacement by the image generation unit does not include an abnormal point detected by the abnormal point detection unit.   4. The second medium image according to claim 1, wherein the second medium image is an image obtained by reading the reference medium that is horizontally moved and placed with respect to the placed state in the first medium image. The image processing device according to one item.   4. The second medium image according to claim 1, wherein the second medium image is an image obtained by reading the reference medium that is rotated and mounted with respect to the mounted state in the first medium image. The image processing device described. The image acquisition unit acquires the second medium image only when an abnormal point is detected from the first medium image by the abnormal point detection unit, according to any one of claims 1 to 5. The image processing device described. When an abnormal point is detected from the first medium image by the abnormal point detection unit, a display for instructing the user to place the reference medium in a state different from that of the first medium image is generated. The image processing apparatus according to claim 6 , further comprising a display generation unit that performs The correction image is an image used for the non-contact scanner shading correction, the image processing apparatus according to any one of claims 1 to 7. The image processing apparatus according to claim 8 , further comprising the non-contact scanner. An image acquisition unit that acquires a first medium image obtained by reading the placed reference medium and a second medium image obtained by reading the reference medium placed in a state different from the first medium image,
An abnormal point detection unit that detects an abnormal point from the first medium image;
An image generation unit that replaces a region including the abnormal point of the first medium image with a region of the second medium image corresponding to the region including the abnormal point, and generates a correction image,
Equipped with
The image processing system , wherein the second medium image is an image obtained by reading the reference medium that is placed upside down with respect to the placement state in the first medium image . Acquiring a first medium image obtained by reading the placed reference medium and a second medium image obtained by reading the reference medium placed in a state different from the first medium image;
Detecting an abnormal point from the first medium image;
A step of replacing a region including the abnormal point of the first medium image with a region of the second medium image corresponding to the region including the abnormal point by the arithmetic processing device to generate a correction image;
Including,
The image processing method , wherein the second medium image is an image obtained by reading the reference medium that is placed upside down with respect to the placement state in the first medium image . An image acquisition unit that acquires a first medium image obtained by reading a reference medium on which a computer is placed and a second medium image obtained by reading the reference medium placed in a state different from the first medium image When,
An abnormal point detection unit that detects an abnormal point from the first medium image;
An image generation unit that replaces a region including the abnormal point of the first medium image with a region of the second medium image corresponding to the region including the abnormal point, and generates a correction image,
Function as
The program , wherein the second medium image is an image obtained by reading the reference medium that is placed upside down with respect to the placement state in the first medium image .

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