JP2008022262A - Image processor and image processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image processor reduced in cost on the whole by providing a simple decision means on a processing path for one surface of an original document. <P>SOLUTION: The image processor comprises: an image input unit 2 which reads in images of top and reverse surfaces of an original document; the simple decision unit 8 which temporarily decides the possibility that code information is embedded in the document on the processing path for processing the first surface of the read document; an inhibition code detector 6 which detects the code information embedded in the document on a processing path for processing a second surface of the read document; and an inverting mechanism which turns over the document. When the simple decision unit 8 temporarily decides that the code information is possibly embedded in the first surface of the document, the inverting mechanism turns over the document, and a control unit 9 makes control so that the inhibition code detector 6 performs code detection of the second surface, and then code detection of the first surface is performed by the inhibition code detector 6. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a technique for preventing unauthorized copying of a document image.

  In recent years, there has been proposed an image forming apparatus having a function of simultaneously reading a front surface and a back surface of a document image in a single document transport operation.

  In an image forming apparatus having such a double-sided simultaneous reading function, Japanese Patent Application Laid-Open No. 2004-151867 detects code information in order to implement a function of reading code information embedded on both sides of a document and restricting copying of the document. A configuration in which detection blocks are provided on both the front side and the back side of the document transport path is disclosed.

  Also, one detection block is prepared, the image data of one surface is stored in the memory, and it is stored in the memory after determining whether the code information is embedded in the image data of the other surface. There is also known a technique for reading out image data of a surface to detect code information.

JP 2005-142917 A

  However, if two detection blocks for detecting the code information for the back surface and the front surface are prepared as in Patent Document 1, the cost of the apparatus increases. In addition, in the technology that prepares one detection block, temporarily stores the image data of one surface in the memory, and sequentially detects the code information for each surface, the detection cost can be reduced because only one detection block is required. However, parallel processing cannot be performed on both-side images, and productivity is reduced.

  Further, the above-described two techniques have a problem that productivity of a normal document is lowered because code information is detected even in a normal document in which code information is not embedded.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide an image processing apparatus and an image processing method in which the cost of an apparatus capable of performing processing according to code information embedded in a document is reduced. .

In order to achieve this object, the image processing apparatus of the present invention embeds code information in a document in a duplex reading unit that reads images on the front and back sides of the document and a processing path that processes the first surface of the scanned document. A provisional determination means for temporarily determining the possibility of printing, a code information detection means for detecting code information embedded in the document in a processing path for processing the second side of the read document, and a front surface and a back surface of the document. When it is temporarily determined that there is a possibility that the code information is embedded in the first surface of the document by the reversing unit for reversing and the provisional determination unit, the document is reversed by the reversing unit and the code detection of the second surface is performed. After the code information is detected by the code information detection means, control means is provided for controlling the code information detection means to perform code detection on the first surface.
Thus, according to the present invention, the cost of the entire apparatus can be reduced by providing simple determination means in the processing path on one side of the document.

In the image processing apparatus, image processing means for performing image processing on the read image data is provided in a processing path for processing the first surface and a processing path for processing the second surface, and the control means When it is determined by the temporary determination means that there is no possibility that code information is embedded in the first surface of the document, the image processing means may execute double-sided image processing.
Therefore, a normal document that does not include code information can simultaneously process both-side images.

  The image processing apparatus includes a storage unit that stores image data, and the control unit temporarily determines that the code information may be embedded in the document on the first surface of the document. Then, the image data of the first surface is stored in the storage means, and after the code detection of the second surface is performed by the code information detection means, the image data of the first surface is read from the storage means. It may be controlled to output to the code information detecting means.

  The image processing apparatus is provided with a double-side reading means for reading images on the front and back sides of the original and a processing path for processing the first and second sides of the read original, and code information is embedded in the original. Tentative determination means for temporarily determining the possibility of being present, and the provisional determination means input image data of a surface that is provisionally determined to have code information embedded in the document, and the code information is embedded in the document It is preferable to have code information detecting means for detecting whether or not the information is detected.

  In the above image processing apparatus, when it is temporarily determined that there is a possibility that code information is embedded in both sides of the document, after the image data on either side is processed by the code information detection unit, It is preferable to have control means for performing control to output the image data of the other surface to the code information detection means.

  In the image processing apparatus, when it is temporarily determined that there is a possibility that the code information is embedded on both sides of the document and the storage means for storing the image data, the image data on the first surface is stored in the storage means. Control means for performing control such that after the code detection of the second surface is performed by the code information detection means, the image data of the first surface is read from the storage means and output to the code information detection means; It is good to have.

  In the image processing apparatus, the temporary determination unit may determine that the code information may be embedded in the document when the density of the background image of the document is equal to or higher than a predetermined threshold value.

  In the image processing apparatus, the temporary determination unit determines that there is no possibility that the code information is embedded in the document when the background image of the document does not include the color component used in the code information. Good.

  In the image processing apparatus, the temporary determination unit determines whether or not a predetermined pattern is included in the background image of the document by pattern matching, and determines whether or not code information is embedded in the document depending on the degree of matching of the pattern matching. It is good to judge.

  The image processing method of the present invention includes a step of reading images of the front and back sides of a document, a step of temporarily determining the possibility that code information is embedded in the document, and a code information embedded on the first surface of the document. And temporarily detecting the code on the second side of the document, and then detecting the code on the first side.

  The present invention can reduce the cost of the entire apparatus by providing a simple determination means in the processing path on one side of the original, and can reduce both sides of a normal original that does not include code information. Images can be processed simultaneously.

  Preferred embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 shows the configuration of an image processing apparatus 1A of the present embodiment.
The image processing apparatus 1A of the present embodiment includes an image input unit 2, a first image processing unit 5, a second image processing unit 7, a prohibited code detection unit 6, a simple determination unit 8, a control unit 9, And an output unit 10. The image input unit 2 includes a first input sensor 3 and a second input sensor 4.

The first input sensor 3 reads an image on the surface of the document with a reduction optical system through the platen glass. The second input sensor 4 reads an image on the back side of the document with a contact type sensor. An example of the image input unit 2 is shown in FIG.
The image input unit 2 of the present embodiment stops the full-rate carriage 73 and the half-rate carriage 75, and uses the CCD image sensor (first input sensor 3) to scan the first surface of the original conveyed on the second platen glass 72. It is possible to read the second side of the document simultaneously with the first side by the CIS 60 as the second input sensor 4 while reading at 78. That is, using the CCD image sensor 78 that is the first input sensor 3 and the CIS 60 that is the second sensor 4, it is possible to simultaneously read the images on the front and back surfaces of the original by conveying the original to the conveyance path once. It is said.

  The image input unit 2 includes a reversing mechanism that reverses the original. This will be described with reference to FIG. The documents placed on the document tray 50 are sequentially supplied to the first conveyance path 51, and the surface of the document is read from below at the position of the platen roll 58 using the CCD image sensor 78 of the scanner device 70. . Then, the transfer path switching gate 59 moves to the fourth transfer path 54 via the third transfer path 53. The document completely passing through the third conveyance path 53 is switched back by the inverter roll 56 and the inverter pinch roll 57 and supplied to the fifth conveyance path 55. The document supplied to the fifth conveyance path 55 is again supplied to the first conveyance path 51. Then, the original is read from below by the CCD image sensor 78 of the scanner device 70. The original at this time is in a state where the front side and the back side are reversed, and the back side, not the front side, of the original is read.

Returning to FIG. 1, the simple determination unit 8 determines the possibility that the code information is embedded in the document with a simple configuration. A determination method of the simple determination unit 8 will be described with reference to FIG.
The simple determination unit 8 counts part or all of the pixel values (density) of one line for the input image data as shown in FIG. If the total pixel value is equal to or greater than the threshold value, it is determined that there is a high possibility that code information is embedded. Of course, the sampling start area for determination may not be the first line. Further, depending on the arrangement of the code information, there is a possibility that the code information may be overlooked only by sampling the first line. Therefore, sampling may be performed for a plurality of lines, and an average value thereof may be obtained and compared with a threshold value.

In some cases, the code information is not black but color toner is used. In such a case, it may be as follows.
Since the code information is also inserted into the image portion of the image, the reproduced color of the code information is often not the original color for the code information overlapping the background image. For example, if the color of the code information is yellow and the background image is magenta, the code information is red that is their secondary color. That is, as a result of simple detection, if only colors having no yellow component such as magenta, cyan, and blue can be detected, it can be determined that the code information is not included in the image. Therefore, if the code information has several predetermined colors, simple detection is possible depending on whether or not the assumed color can be detected.

  Further, when the simple determination is performed with the entire surface of the original image as a monitoring target, there is a region having a background color density, although it is not related to the code information. If such a region is simply determined, there is a possibility of erroneous determination that there is code information.

Therefore, as shown in FIG. 4, the simple determination unit 8 includes a floating binarization unit 15 and a pattern matching unit 16. The input image data is converted into an ON / OFF binary image by the floating binarization unit 15, and pattern matching with a predetermined pattern image is performed by the pattern matching unit 16.
FIG. 5 shows image data for two lines used for pattern matching, and FIG. 6 shows an example of a pattern image when code information is included.

  The first image processing unit 5 and the second image processing unit 7 are processing units that perform image processing generally performed conventionally, and perform processing such as sharpness adjustment, gradation adjustment, and color conversion. .

The prohibition code detection unit 6 will be described. FIG. 7 shows a detailed configuration of the prohibition code detection unit 6.
The image data output from the first input sensor 3 is input to the gray scale conversion unit 21 and converted from full color to gray scale. Thereafter, it is binarized by the binarization processing unit 22.

  The binarized image data is input to the noise removal processing unit 23, and noise removal processing is performed. Specifically, a pixel block in which black pixels are connected is obtained, and each pixel of the pixel block whose size (number of connected pixels) is not within a predetermined range is replaced with a white pixel. The predetermined range is set to an appropriate range so that the hatched pattern is not deleted, and other patterns (isolated dot patterns, characters and figures in the document, etc.) are deleted.

  The image data from which noise has been removed is input to the pattern detection processing unit 24, where two types of oblique line pattern detection processing are performed, and the result is output as image data of 2 bits per pixel. Specifically, detection is performed by template matching by applying the patterns shown in FIGS. 8A and 8B at the positions of the respective pixels in the image data. Here, when the pattern (A) shown in FIG. 8 is detected, the pixel value 0 is output, and when the pattern (B) shown in FIG. 8 is detected, the pixel value 1 is output and the pattern is not detected. , Pixel value 2 is output.

  The image data output from the pattern detection processing unit 24 is input to the blocking processing unit 25. Here, the block size is set to a size smaller than half the size of the copy prohibition code and the condition code, and is set to a size such that one or more blocks are completely included in the code. The blocking processing unit 25 divides the input image data into blocks of a predetermined size and outputs them to the number calculation unit 26.

  The number calculation unit 26 calculates the number of pixels having a pixel value 0 and the pixel having a pixel value 1 in the block, and outputs the result to the ratio calculation unit 27. The total is output to the determination processing unit 28. The ratio calculation unit 27 calculates the ratio of pixels with a pixel value of 0 and outputs the result to the determination processing unit 28.

  The determination processing unit 28 performs determination processing based on the total number input from the number calculation unit 26 and the ratio input from the ratio calculation unit 27.

  In the present embodiment, a plurality of copy prohibition codes with all bits 0 inside the block and a plurality of copy prohibition codes with all bits 1 inside the block are embedded in the image.

  When the inside of the block being processed is located inside the copy prohibition code of all bits 0, a hatched pattern corresponding to a predetermined number of bits 0 or more is detected in the block and corresponds to bit 1 Since the hatched pattern is hardly detected, the ratio of the hatched pattern corresponding to bit 0 is high and should be nearly 1.0.

  If the block currently being processed is located inside the copy prohibition code of all bits 1, a hatched pattern corresponding to a predetermined number of bits 1 or more is detected in the block, and bit 0 is set. Since the corresponding diagonal pattern is hardly detected, the ratio of the diagonal pattern corresponding to bit 0 should be low and almost close to 0.0.

The following determination process is performed using the above characteristics.
If the total number> the first threshold value and the ratio> the second threshold value, the block is determined to be the copy prohibition code 0.
If the total number> the first threshold value and (1-ratio)> the second threshold value, the block is determined to be the copy prohibition code 1.
In cases other than the above, it is determined that the block is not a copy prohibition code. Also, the first threshold value is set by adding a margin to the number of theoretical patterns included in the block from the block size and pattern size. The second threshold value is set to a value close to 1.0.

  The determination processing unit 28 separately counts the number of blocks determined to be the copy prohibition code 0 and the number of blocks determined to be the copy prohibition code 1. When the number of blocks determined as copy prohibition code 0 is equal to or greater than threshold value 3 and the ratio determined as copy prohibition code 0 is a value close to 1.0, the image is determined to be a copy prohibition document; The determination result is output to the control unit 9.

  The control unit 9 causes the first image processing unit 5 and the prohibition code detection unit 6 to output the image data read by the first input sensor 3. Also, the image data read by the second input sensor 4 is output to the second image processing unit 7 and the simple determination unit 8. When the simple determination unit 8 determines that there is a possibility that there is a copy prohibition code in the back image, the control unit 9 inverts the document by the inversion mechanism and causes the first input sensor 3 to read the back image. After the first image processing unit 5 and the forbidden code detecting unit 6 finish processing the front surface image, the first image processing unit 5 and the forbidden code detecting unit 6 process the back side image data read by the first input sensor 3. .

  If the determination result of the back image by the simple determination unit 8 is that there is no possibility of the copy prohibition code, the control unit 9 uses the back image input to the second image processing unit 7 as it is. The two-image processing unit 7 performs processing, and the processed back-side image data is output to the output unit 10.

The processing procedure of the present embodiment will be described with reference to the flowchart shown in FIG.
When scanning of the front and back side originals is started (step S1 / YES), the read image data of the front side is output to the first image processing unit 5 and the prohibition code detection unit 6. The back side image data is output to the second image processing unit 7 and the simple determination unit 8 (step S2). And the simple determination part 8 performs the simple determination of back surface image data (step S3). The first image processing unit 5 and the second image processing unit 7 perform normal image processing such as image data sharpness adjustment, gradation adjustment, and color conversion.

  If the simple determination result of the back surface image data in the simple determination unit 8 indicates that there is a possibility that there is a copy prohibition code (step S4 / YES), the control unit 9 controls the reversing mechanism to invert the document, The back side image data is read by the first input sensor 3. Then, the prohibition code detection unit 6 waits for the determination result of the surface image data to be output. When the copy prohibition code is detected in the front image by the prohibition code detection unit 6 (step S7 / YES), the front surface copy operation is prohibited (step S8). For example, the action of prohibiting the copying operation includes stopping the operation of the machine, painting the image in black, and outputting a blank sheet. If the copy prohibition code is not detected in the front image by the prohibition code detector 6 (step S7 / NO), the front image data is output to the output unit 10 (step S9).

  Next, the back side image data read by the first input sensor 3 is output to the prohibition code detection unit 6 and the first image processing unit 5 (step S10). Then, the copy prohibition code is detected by the prohibition code determination unit 6 for the back side image data (step S11). If there is a copy prohibition code in the back side image data (step S11 / YES), the above-described copy prohibition operation is performed (step S12). If no copy prohibition code is detected on the back side (step S11 / NO), the back side image data subjected to image processing by the first image processing unit 5 is sent to the output unit 10 (step S13).

  Furthermore, when the simple determination result in step S4 is that there is no possibility of the copy prohibition code (step S4 / NO), the back side is subjected to the same image processing by the second image processing unit 7 provided for the back side, The processed back surface image data is output to the output unit 10 (step S5).

  As described above, in this embodiment, only one prohibition code detection unit is used for the surface, and the cost of the apparatus can be reduced. In addition, parallel processing is possible when a document having no copy prohibition code is sent on both sides or the back side. That is, the productivity that is the greatest feature of the double-sided simultaneous processing can be maintained. Further, in this embodiment, since a memory for temporarily storing the read image data is not necessary, the cost of the memory can be suppressed. Further, in this example, the method of providing the simple detection unit on the back surface side is shown, but conversely, the configuration having the simple detection unit on the surface may be employed.

  The configuration of this embodiment is shown in FIG. The present embodiment includes a memory 20 in addition to the configuration of the first embodiment described above. The memory 20 stores the back side image data read by the second input sensor 4, and outputs the stored back side image data to the first image processing unit 5 and the prohibition code detection unit 6. The first input sensor 3, the second input sensor 4, the first image processing unit 5, the second image processing unit 7, the simple determination unit 8, the prohibition code detection unit 6, and the output unit 10 are the same as in the first embodiment. It is the composition.

  In this embodiment, when the simple determination unit 8 determines that there is a possibility that the back side image data includes a copy prohibition code, the back side image data is stored in the memory 20. When the processing of the front image data is completed by the first image processing unit 5 and the prohibition code detection unit 6, the back side image data is read from the memory 20 and output to the first image processing unit 5 and the prohibition code detection unit 6. To do.

  The processing procedure of this embodiment will be described with reference to the flowchart shown in FIG. When scanning of the front and back side originals is started (step S21 / YES), the read front side image data is output to the first image processing unit 5 and the prohibition code detection unit 6. The back side image data is output to the second image processing unit 7 and the simple determination unit 8 (step S22). And the simple determination part 8 performs the simple determination of back surface image data (step S23). The first image processing unit 5 and the second image processing unit 7 perform normal image processing such as image data sharpness adjustment, gradation adjustment, and color conversion.

When the simple determination result of the back side image data in the simple determination unit 8 may include a copy prohibition code (step S24 / YES), the control unit 9 reads the back side read by the second input sensor 4. Are stored in the memory 20 (step S26). Then, the prohibition code detection unit 6 waits for the determination result of the surface image data to be output. When the copy prohibition code is detected in the front image by the prohibition code detection unit 6 (step S27 / YES), a copy prohibition operation such as blackening the front image as described above is performed (step S28).
If the copy prohibition code is not detected in the front image by the prohibition code detector 6 (step S27 / NO), the front image data is sent to the output unit 29 (step S29) and stored in the memory 20. The back side image data is read out and output to the prohibition code detection unit 6 and the first image processing unit 5 (step S30).

  The prohibition code detection unit 6 determines whether or not there is a copy prohibition code in the image data on the back side as with the front side (step S31). If it is determined that the copy prohibition code is present (step S31 / YES), as described above, a copy prohibition operation such as painting the back image black is performed (step S32). If it is determined that there is no copy prohibition code in the back side image data (step S31 / NO), the back side image data subjected to image processing in the same manner as the front side is sent to the output unit 10 (step S33). It is assumed that the image processing of the back image has been performed first by the second image processing unit 7.

  Furthermore, when the determination result of the simple determination unit 8 indicates that there is no possibility that the back side image data includes a copy prohibition code (step S24 / NO), the second image processing unit 7 provided for the back side uses the same image as the front side. Processing is performed and the image is sent to the output unit 10 (step S25).

  As described above, this embodiment also requires only one prohibition code detection unit for the surface, and can reduce the cost of the apparatus. Further, when a document without a prohibition code is sent on both sides or the back side, parallel processing is possible. That is, productivity, which is the greatest feature of both sides simultaneously, can be maintained. In addition, although the present Example also showed the method provided with a simple detection part on the back surface side, the structure provided with a simple detection part on the surface conversely may be sufficient.

  The configuration of this embodiment is shown in FIG. In this embodiment, a first simple determination unit 30 and a second simple determination unit 31 are provided. The first simple determination unit 30 performs simple determination on the surface image data read by the first input sensor 3. Similarly, the second simple determination unit 31 performs simple determination on the back side image data read by the second input sensor 4. The selector 32 switches an image to be sent to the prohibition code detection unit 6 under the control of the control unit 9. In the following, for the sake of simplification of explanation, a case where the image data of the front surface is input by the first input sensor 3 and the image data of the back surface is input by the second input sensor 4 will be described as an example. The back side image data may be input by the input sensor 3, and the front side image data may be input by the second input sensor 4.

The processing procedure of the present embodiment will be described with reference to the flowcharts shown in FIGS. When scanning of the front side document and the back side document is started (step S41 / YES), the first simple determination unit 30 performs simple determination of the read front side image data, and the second simple determination unit 31 performs simple determination of the back side image data. (Step S42). At this time, the image data of the surface is also output to the first image processing unit 5 and subjected to image processing. Similarly, the back side image data is also output to the second image processing unit 7 and is subjected to image processing.
When the simple determination between the first simple determination unit 30 and the second simple determination unit 31 determines that there is a possibility that the copy prohibition code is included on both sides (step S43), the control unit 9 switches the selector 32 over. First, the image data of the surface read by the first input sensor 3 is sent to the prohibition code detection unit 6. At this time, the controller 9 reverses the document using the reversing mechanism, and reads the image data on the back surface with the first input sensor 3 (step S45).

  Thereafter, the image data of the front surface image-processed by the first image processing unit 5 and the image data of the back surface image-processed by the second image processing unit 7 are respectively output to the output unit 10 (step S46).

  If the determination result of the image data on the surface output to the prohibition code detection unit 6 is that there is a copy prohibition code (step S47 / YES), the copying operation is prohibited (step S48). If the determination of the front side image data by the prohibition code detection unit 6 is that there is no copy prohibition code (step S47 / NO), the reverse side image data read by the first input sensor 3 is controlled by the selector 32. It outputs to the detection part 6 (step S49). If the prohibition code detection unit 6 determines that there is a copy prohibition code in the back side image data (step S50 / YES), the copy operation is prohibited (step S51). When the prohibition code detection unit 6 determines that there is no copy prohibition code in the back side image data (step S50 / NO), copying is permitted (step S52), and the output unit 10 forms an image.

Next, a processing procedure in a case where it is simply determined that there is a possibility that the copy prohibition code may be included only in the surface image data will be described with reference to the flowchart shown in FIG.
When the first simple determination unit 30 tentatively determines that there is a copy prohibition code only in the front image data (step S61 / YES), the control unit 9 controls the selector 32 to convert the front image data into the prohibition code. It outputs to the detection part 6 (step S62). Then, the front side image data processed by the first image processing unit 5 and the back side image data processed by the second image processing unit 7 are output to the output unit 10 (step S63). If the prohibition code detection unit 6 determines that there is a copy prohibition code in the surface image data (step S64 / YES), the copying operation is prohibited (step S65). If the prohibition code detector 6 determines that there is no copy prohibition code in the front image data (step S64 / NO), the copying operation is permitted (step S66).

In addition, when the determination result of step S61 is NO, there are a case where the copy prohibition code is included only in the back side image data and a case where there is no possibility that the copy prohibition code is included on both sides. The processing procedure in this case will be described with reference to the flowchart shown in FIG.
When the second simple determination unit 31 tentatively determines that there is a copy prohibition code only in the back side image data (step S71 / YES), the control unit 9 controls the selector 32 to convert the back side image data into the prohibition code. It outputs to the detection part 6 (step S73). Then, the front side image data processed by the first image processing unit 5 and the back side image data processed by the second image processing unit 7 are output to the output unit 10 (step S74). If the prohibition code detector 6 determines that there is a copy prohibition code in the back side image data (step S75 / YES), the copy operation is prohibited (step S76). If the prohibition code detector 6 determines that there is no copy prohibition code in the back side image data (step S75 / NO), the copying operation is permitted (step S77). If it is temporarily determined that there is no possibility of including a copy prohibition code on both sides (step S71 / NO), the surface image data processed by the first image processing unit 5 and the second image processing unit 7 The processed back surface image data is output to the output unit 10 as it is (step S72).

  As described above, this embodiment can maintain the productivity without using the reverse path if it is determined that there is a possibility of only one side.

  The configuration of this embodiment is shown in FIG. In the present embodiment, a memory 20 is added to the third embodiment described above.

  The processing procedure of this embodiment will be described with reference to the flowchart shown in FIG. When the first simple determination unit 30 and the second simple determination unit 31 determine that there is a possibility that the copy prohibition code is included on both sides (step S83 / YES), the control unit 9 controls the selector 32 to control the first surface. The image data of (front or back) is output to the prohibition code detection unit 6 (step S84), and the image data of the second surface (back or front) is stored in the memory 20 (step S85). Then, the front side image data processed by the first image processing unit 5 and the back side image data processed by the second image processing unit 7 are output to the output unit 10 (step S86).

  If the prohibition code detector 6 determines that there is a copy prohibition code in the image data on the first side (step S87 / YES), the copying operation of the image data on the first side is prohibited (step S88). If it is determined that there is no copy prohibition code in the image data on the first side (step S87 / NO), the image data on the second side is read from the memory 20 and output to the prohibition code detection unit 6 (step S89). If the prohibition code detector 6 determines that there is a copy prohibition code in the image data on the second side (step S90 / YES), the copying operation of the image data on the second side is prohibited (step S91). If the prohibition code detection unit 6 determines that there is no copy prohibition code in the image data on the second side (step S90 / NO), the copying operation of the image data is permitted (step S92).

  When it is determined that there is a possibility that only the front surface image data includes the copy prohibition code, the control unit 9 controls the selector 32 to send the front surface image data to the prohibition code detection unit 6. At this time, the image data on the front and back surfaces are subjected to image processing by the first image processing unit 5 and the second image processing unit 7 respectively, and the processed image data are sequentially sent to the output unit 10. When the prohibition code detection unit 6 determines that there is a copy prohibition code, a copy prohibition operation is performed. If it is determined that there is no copy prohibition code, the output unit 10 performs a normal copying operation. The same applies when it is determined that there is a possibility that the copy prohibition code is included only in the back side image data. This processing procedure is performed in the same procedure as the flowcharts shown in FIGS.

  As described above, in this embodiment, when it is determined that there is a possibility that the copy prohibition code is included on one side of the document, the image data is not stored in the memory 20, so that productivity can be maintained.

  The simple determination of the above-described first to fourth embodiments has been described on the assumption that the determined result will not be covered thereafter. However, in order to reliably detect the copy prohibition code, the copy prohibition code is added to the entire surface of the copy prohibition document. Therefore, the simple determination can be continued after the simple determination is performed on the image data at the leading edge of the document. In such a case, the simple determination result may be changed on the way. As a situation to be changed, there is a blank area intentionally and intentionally at the leading edge (it is determined that there is no possibility of including a copy prohibition code at this point), and a copy prohibition code is added after the middle of the document. (It is determined that there is a possibility that a copy prohibition code is included at this time).

  If it is determined that there is a possibility that the copy prohibition code is included in the simple detection of the leading edge image of the document, the prohibition code detection unit 6 performs processing, so that the prohibition determination and the prohibition operation can be performed reliably. However, after it is determined that there is no possibility that the copy prohibition code is included in the simple detection of the leading edge image of the document, the result of the simple determination that is continuously monitored changes from the possibility that the copy prohibition code is included to the presence. In such a case, copying may be permitted without the code detection using the copy prohibition code 6 by the prohibition code detection unit 6. A control example for correctly determining copy prohibition in such a situation will be described below. The circuit configuration is the same as that of the first to fourth embodiments.

  First, the case of the configuration of the first embodiment will be described. In the case of the first embodiment, the image data of the front surface is sent to the prohibition code detection unit 6 regardless of the result of the simple determination at the front end of the back surface image. Therefore, there is no particular problem with the surface image data. However, when the simple determination of the back side image by the simple determination unit 8 changes from the possibility that the copy prohibition code is included to the presence, the original is reversed by the reversing mechanism after the original is pulled back, and is the same as the front image. The prohibition code detection unit 6 detects a copy prohibition code of the back side image data. Since the pull back operation is also an operation necessary for reversing the document, it is possible to perform a process of pulling back the document using the reversing mechanism.

  Further, since the front surface processing has been completed, the original is not reversed, and the pulled-back original is read again by the second input sensor 4 on the back surface, and the image is sent to the prohibition code detection unit 6 provided on the front side. With such a circuit configuration, it is possible to save time for the document reversing operation.

  Next, the case of Example 2 will be described. In the second embodiment, the back side image data is stored in the memory 20 regardless of the result of the simple determination at the front end of the back side image data. When the simple determination result of the back side image data changes from the possibility of including the copy prohibition code to the presence, the back side image data is read from the memory 20 and output to the prohibition code detection unit 6. After the copy prohibition code detection determination for the front image data, the prohibition code detection unit 6 performs a copy prohibition code detection determination for the back image data.

Next, the case of Example 3 will be described. In the third embodiment, even if both the simple determination results of the first simple determination unit 30 and the second simple determination unit 31 are determined not to include a copy prohibition code, the image on one of the surfaces is displayed. For the data, it is assumed that the copy prohibition code is detected by the prohibition code detection unit 6.
If the result of the simple determination of the surface where the copy prohibition code is not detected by the prohibition code detection unit 6 changes from no possibility of including the copy prohibition code to yes, the original is pulled back and the copy prohibition code is not detected. Reread the surface image data. (Normally, since the prohibition code is likely to be arranged on the surface, it is desirable that the detection process in the prohibition code detection unit 6 always prioritize the surface.)

  Next, the case of Example 4 will be described. In the case of the fourth embodiment, regardless of the simple tip determination results of the first simple determination unit 30 and the second simple determination unit 31, the front or back side image data is sent to the prohibition code detection unit 6 and the copy prohibition code Perform detection. Further, the image data of the surface not sent to the prohibition code detection unit 6 is stored in the memory 20. When the determination of the simple detection result of the surface stored in the memory 20 changes from the possibility of including the copy prohibition code to the presence, it is first sent to the prohibition code detection unit 6 as in the second embodiment. After the surface image prohibition determination processing, the image data of the opposite surface is read from the memory 20 and sent to the prohibition code detection unit 6 to execute the copy prohibition code detection processing.

  The embodiment described above is a preferred embodiment of the present invention. However, the present invention is not limited to this, and various modifications can be made without departing from the scope of the present invention.

It is a block diagram which shows the structure of the image processing apparatus of 1st Example. It is a figure which shows the structure of a 1st input sensor, a 2nd input sensor, and an inversion mechanism. It is a figure for demonstrating the method of the simple determination by the density determination of a ground color. 3 is a diagram illustrating a configuration of a simple determination unit 8. FIG. It is a figure for demonstrating the method of the simple determination by pattern matching. It is a figure which shows an example of a pattern in the case of possibility of containing a copy prohibition code. 4 is a block diagram showing a configuration of a prohibition code detection unit 6. It is a figure which shows an example of the image used for template matching. It is a flowchart which shows the process sequence of 1st Example. It is a block diagram which shows the structure of the image processing apparatus of 2nd Example. It is a flowchart which shows the process sequence of 2nd Example. It is a block diagram which shows the structure of the image processing apparatus of 3rd Example. It is a flowchart which shows the process sequence of 3rd Example, and is a flowchart which shows a procedure at the time of determining with possibility that a copy prohibition code | cord | chord is included in both surfaces of a document. It is a flowchart which shows the process sequence of 3rd Example, and is a flowchart which shows a procedure at the time of carrying out provisional determination with possibility that a copy prohibition code | cord | chord is included on the surface. It is a flowchart which shows the process sequence of 3rd Example, and is a flowchart which shows a procedure at the time of provisionally determining with the possibility that a copy prohibition code is included in a back surface. It is a block diagram which shows the structure of the image processing apparatus of 4th Example. It is a flowchart which shows the process sequence of 4th Example, and is a flowchart which shows a procedure at the time of determining with possibility that a copy prohibition code | cord | chord is included in both surfaces of a document.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image processing apparatus 2 Image input part 3 1st input sensor 4 2nd input sensor 5 1st image processing part 6 Prohibition code detection part 7 2nd image processing part 8 Simple determination part 9 Control part 10 Output part

Claims (10)

A double-sided scanning means for scanning images on the front and back sides of the document;
Provisional determination means for tentatively determining the possibility that code information is embedded in the document in the processing path for processing the first surface of the read document;
Code information detecting means for detecting code information embedded in the document in a processing path for processing the second side of the read document;
Reversing means for reversing the front and back sides of the document;
If it is temporarily determined that the code information may be embedded in the first surface of the document by the temporary determination means, the document is reversed by the reversing means, and the code information detection of the code detection of the second surface is performed. Control means for performing control so that code detection of the first surface is performed by the code information detection means after being performed by the means;
An image processing apparatus comprising: Image processing means for performing image processing on the read image data in a processing path for processing the first surface and a processing path for processing the second surface;
The control unit causes the image processing unit to execute double-sided image processing when the temporary determination unit determines that there is no possibility that code information is embedded in the first side of the document. The image processing apparatus according to claim 1. Having storage means for storing image data;
The control unit stores the image data of the first surface in the storage unit when the provisional determination unit tentatively determines that the code information may be embedded in the document on the first side of the document. And after the code detection of the second surface is performed by the code information detection means, the image data of the first surface is controlled to be read from the storage means and output to the code information detection means. The image processing apparatus according to claim 1 or 2. A double-sided scanning means for scanning images on the front and back sides of the document;
Provisional determination means provided in each of processing paths for processing the first and second surfaces of the read document, and temporarily determining the possibility that code information is embedded in the document;
Code information detection means for detecting whether or not the code information is embedded in the document by inputting the image data of the surface temporarily determined that the code information may be embedded in the document by the temporary determination means When,
An image processing apparatus comprising:   When it is temporarily determined that there is a possibility that code information is embedded in both sides of the document, the image data of the other side is processed after the image data of one side is processed by the code information detecting means. The image processing apparatus according to claim 4, further comprising a control unit that performs control for causing the code information detection unit to output the data. Storage means for storing image data;
When it is temporarily determined that there is a possibility that the code information is embedded on both sides of the document, the image data of the first side is stored in the storage unit, and the code detection of the second side is performed by the code information detection unit. Control means for controlling the image data of the first surface to be read from the storage means and output to the code information detection means after being performed;
The image processing apparatus according to claim 4, further comprising:   7. The provisional determination unit determines that there is a possibility that code information is embedded in the document when the density of the background image of the document is equal to or higher than a predetermined threshold value. The image processing apparatus according to claim 1.   The provisional determination unit determines that there is no possibility that the code information is embedded in the document when the background image of the document does not include the color component used in the code information. Item 7. The image processing apparatus according to any one of Items 1 to 6.   The provisional determination means determines whether or not a predetermined pattern is included in the background image of the document by pattern matching, and determines whether or not code information is embedded in the document based on the matching degree of the pattern matching. The image processing apparatus according to claim 1, wherein the image processing apparatus is characterized. Reading the front and back images of the document;
Tentatively determining the possibility that code information is embedded in the manuscript;
If it is temporarily determined that there is a possibility that code information is embedded on the first side of the document, the code is detected on the first side after detecting the code on the second side of the document;
An image processing method comprising:

Images