JPH07123254A - Image forming device - Google Patents

Abstract

PURPOSE:To conduct discrimination processing of various kinds of originals whose copying is inhibited at a proper processing time by revising an output state of an output image depending on the result of recognition of repetitive pattern appeared repetitively in an input image of an original. CONSTITUTION:A copy inhibit original discrimination section 104 uses a link component detection section 201 receiving picture data to threshold process and detect picture data and extracts an image whose link component size is smaller than a predetermined size as a pattern and detects a succeeding link component when the size is the predetermined size or over. The pattern is recognized by extracting a characteristic quantity of the extracted pattern and the characteristic quantity and the pattern are stored in memory 202. When the processing to all linked components finishes, a repetition extract section 203 references the content of the memory 202 to extract a repetitive pattern. When the extraction by the extract section 203 finishes, a control section 204 transfers a revision command of an output state of the output image to the image processing section 102 when any repetitive pattern exists based on the result of extract by the extract section 203, and outputs a command representing no revision of the output image when no repetitive pattern exists.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having a copy-prohibited document discriminating function for discriminating whether or not an inputted document image is a document image for which copying is prohibited. The present invention relates to an image forming apparatus that discriminates a document image for which copying is prohibited by recognizing a repeated pattern that appears repeatedly in the document image.

[0002]

2. Description of the Related Art In recent years, due to improvements in image processing technology and image forming technology, it has become possible to carry out delicate copying such that copy bills copied by a color copying machine and actual bills cannot be easily distinguished. Therefore, an image forming apparatus has been developed which has a copy-prohibited document discrimination function of discriminating copy-prohibited documents such as bills and securities and prohibiting the use of copy-prohibited documents.

As a method of discriminating a copy-inhibited document, for example, a method of using a pattern matching method as disclosed in Japanese Patent Application Laid-Open No. 2-83571 "Image recording apparatus" is generally used. In this apparatus, it is determined whether or not the original is a copy-inhibited original based on the input image data and the pattern data registered in advance.

A related specific color image detecting technique for preventing illegal copying is disclosed in, for example, Japanese Patent Laid-Open No. 4-546.
Methods disclosed in Japanese Patent No. 81 and Japanese Patent Laid-Open No. 4-205274 are known.

[0005]

However, according to the above-mentioned conventional technique, in order to discriminate the copy-prohibited document, it is necessary to register in advance the specific image in the copy-prohibited document to be discriminated. Therefore, there is a problem that it is not possible to discriminate a copy-protected document for which pattern data is not registered as a copy-protected document.

It should be noted that pattern data may be registered in advance for all copy-inhibited documents in order to reliably identify copy-inhibited documents. For example, banknotes, securities, and trains are included in copy-inhibited documents. There are various kinds of tickets such as tickets, gift certificates, various tickets, etc.,
It is impossible to register all the pattern data, and in reality, the pattern data of a copy-prohibited document, which has a great social impact on paper money and the like, is preferentially and selectively registered.

In addition, for example, when the pattern data of a copy-inhibited document which is highly likely to be copied is registered indefinitely, pattern matching takes time in proportion to the number of registered pattern data. There are also problems that the process of distinguishing forbidden documents becomes long, and that false detection and misclassification may occur frequently.

The present invention has been made in view of the above, and it is possible to perform the discrimination processing of many kinds of copy-inhibited originals in an appropriate processing time and without increasing the number of erroneous detections / discriminations. The purpose of 1.

Further, the present invention has been made in view of the above, and it is possible to perform many kinds of copy inhibition document discrimination processing without the need to register a specific image in a copy inhibition document as pattern data. The second purpose.

[0010]

In order to achieve the above-mentioned object, the present invention is an image having a copy-prohibited document discrimination function for discriminating whether or not the inputted document image is a document image for which copying is prohibited. In the forming apparatus, a repeating pattern recognition means for recognizing a repeating pattern repeatedly appearing in the input original image, and an output image change for changing the output state of the output image according to the recognition result of the repeating pattern recognition means. And an image forming apparatus provided with the means.

When the pattern satisfying a predetermined condition is detected from the input original image, the repetitive pattern recognizing means extracts and extracts a feature amount used for recognizing the repetitive pattern from the pattern. The feature pattern is used to perform the repeating pattern recognition process.

Further, the output image changing means changes the appearance frequency of the repeating pattern in the output image when the repeating pattern is recognized, or a part or all of the repeating pattern in the output image. Transform or
And rotating or changing the hue of a part or all of the repeating pattern in the output image.

In order to achieve the above object, the present invention provides an image forming apparatus having a copy-prohibited document discrimination function for discriminating whether or not the inputted document image is a document image for which copying is prohibited. Repeating pattern recognition means for recognizing a repeating pattern repeatedly appearing in the input original image; output image changing means for changing an output state of an output image according to a recognition result of the repeating pattern recognition means; A repeating pattern dictionary means for storing the feature amount of the pattern recognized as the repeating pattern by the repeating pattern recognizing means, and the repeating pattern recognizing means is provided with a pattern satisfying a predetermined condition from the input original image. If detected,
A feature amount used for recognizing the repeating pattern is extracted from the pattern, the repeated pattern recognition process is performed using the extracted feature amount, and the feature amount that matches the recognized feature amount of the repeating pattern is the repeat amount. An image forming apparatus is provided which stores the feature amount of the repeating pattern in the repeating pattern dictionary means when it is not stored in the returning pattern dictionary means.

The repeating pattern recognizing means repeats the corresponding pattern when the characteristic quantity matching the characteristic quantity extracted from the pattern satisfying the predetermined condition is stored in the repeating pattern dictionary means. In the pattern recognition process, the recognition condition is changed so that it can be easily recognized as a repeating pattern, or the characteristic amount matching the characteristic amount extracted from the pattern satisfying the predetermined condition is stored in the repeating pattern dictionary means. If so, the corresponding pattern shall be recognized as a repeating pattern.

Further, the output image changing means changes the appearance frequency of the repeating pattern in the output image when the repeating pattern is recognized, or a part or all of the repeating pattern in the output image. Transform or
And rotating or changing the hue of a part or all of the repeating pattern in the output image.

[0016]

The image forming apparatus of the present invention pays attention to the fact that a specific pattern repeatedly appears in a copy-inhibited document for which copying is legally prohibited, and a repetitive pattern that appears repeatedly in the input document image is considered. By recognizing and changing the output state of the output image according to the recognition result of the repeated pattern, it is possible to see at a glance that the copy-inhibited original is not copied in a perfect state and is a copy.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A color digital copying machine to which an image forming apparatus of the present invention is applied will be described below in detail in the order of [First Embodiment], [Second Embodiment], and [Third Embodiment] with reference to the drawings. To do.

[Embodiment 1] FIG. 1 shows a schematic configuration of a color digital copying machine which is an image forming apparatus according to Embodiment 1, with respect to a scanner 101 for inputting an original image and image data input by the scanner 101. An image processing unit 102 that performs various types of image processing, a printer 103 that inputs image data from the image processing unit 102 and outputs the image data to recording paper, and a scanner 10.
Image data is input from 1 to determine whether the original image is a copy-inhibited document and output a copy-inhibited document determination unit 104 that outputs an instruction to change the output state of the output image. An operation display unit 105 for setting and displaying various messages, and a system controller 106 for controlling the above units are provided.

The scanner 101 scans an original image into R, G, and B by performing three scanning operations corresponding to R, G, and B colors.
It is inputted as three color analog signals of G and B, subjected to A / D conversion to convert the analog signal into a digital signal, further subjected to MTF correction, and outputted as R, G and B image data.

When the R, G, and B image data (here, luminance data) is input, the image processing unit 102 performs γ correction and further solves the masking equation to obtain Y, M, and
The image data is converted into image data (density data) of four colors C and K, and is further subjected to printer γ correction in order to match the characteristics of the printer 103 and output to the printer 103.

When the printer 103 inputs image data (digital signals) of four colors of Y, M, C and K, it performs D / A conversion to convert the digital signals into analog signals, and the converted analog signals of each color. Based on the above, the laser light writing system is driven and toner development is performed to sequentially output to the recording paper, and after the four colors are combined on the recording paper, the paper is discharged.

On the other hand, the copy-prohibited document discriminating unit 104, which is a main part of the present invention, pays attention to the fact that a specific pattern repeatedly appears in a copy-prohibited document for which copying is legally prohibited, and the input document is input. Repetitive pattern that appears repeatedly in the image is recognized, and according to the recognition result of the repeated pattern,
The output state of the output image is changed. The copy-prohibited document discriminating unit 104 reads the R, G,
When the image data of B is input, and in parallel with the process of the image processing unit 102, the below-described copy prohibited document determination process is executed and the repeating pattern is recognized, the image processing unit 102
An instruction to change the output state of the output image is output to.

FIG. 2 is a copy prohibited document discriminating section 1 of the first embodiment.
04 shows a configuration of a connected component detecting unit 201 for extracting a connected component satisfying a predetermined condition from the input image data and extracting a feature amount of the extracted connected component, and a connected component extracted by the connected component detecting unit 201. Of the connected component stored in the memory 202 after the connected component detecting unit 201 completes the extraction of the connected component and the memory 202 for storing the connected component and its position (address). , A repeat extraction unit 203 that extracts (recognizes) a repeat pattern that repeatedly appears in a fixed cycle from all extracted connected components, and a detection result of the repeat pattern extracted by the repeat extraction unit 203, And a copy-prohibited document discrimination control unit 204 that changes the output state of the output image.

In the above structure, the connected component detecting section 201, the memory 202 and the repetitive extracting section 203 constitute the repetitive pattern recognizing means of the present invention. Also,
The copy prohibited document discrimination control unit 204 corresponds to the output image changing unit.

The operation of the above configuration will be described. FIG. 3 shows a processing flow of the discrimination processing of the copy prohibited document of the first embodiment. First, a document image is input by the scanner 101 (S301). The image data input by the scanner 101 is sent to the image processing unit 102 and the copy-prohibited document discrimination unit 104.

The copy-prohibited document discrimination unit 104 is the scanner 1
When the image data is input from 01, first, the connected component detecting unit 201 binarizes the image data (here, multivalued digital signal) (S302), detects the connected component (S303), and determines the size of the connected component. An image smaller than a certain fixed value (condition value of a preset repeating pattern) is extracted as a pattern, and if the connected component is a certain value or more, the process returns to S303 to detect the next connected component (S3).
04). Then, the pattern is recognized by extracting the feature amount of the extracted pattern (S305), and the memory 2
The feature amount and the position of the pattern are stored in 02 (S30).
6). The processes of S303 to S306 up to this point are executed for all the connected components in the input image data.

S303 to S30 for all connected components
When the process of 6 is completed, the repeat extraction unit 203 causes the memory 2
By referring to the feature amount and the position of the pattern stored in No. 02, it is detected whether or not the same pattern (that is, the same feature amount) repeatedly appears in a constant cycle, and the repetitive pattern is extracted (S307). ). Specifically, for example, when the same pattern appears a certain number of times (threshold value) or more and appears in a certain fixed period, it is extracted as a repeating pattern.

When the extraction of the repeating pattern by the repeating extraction unit 203 is completed, the copy-prohibited document discrimination control unit 204 determines the presence or absence of the repeating pattern based on the extraction result (recognition result) of the repeating extraction unit 203. If there is a repeating pattern, the instruction to change the output state of the output image and the position (address) of the repeating pattern are transferred to the image processing unit 102. If there is no repeating pattern, the image processing unit 102 is transferred. An instruction to change the output image is output to (S308).

When the image processing unit 102 receives the instruction to change the output state of the output image and the position of the repeating pattern, the image processing unit 102 corrects the image of the repeating pattern and transfers it to the printer 103 (S309). If an instruction to change the output image is input, the output image is transferred to the printer 103 after performing normal image processing.

The printer 103 outputs the image data input from the image processing unit 102 onto recording paper (S310).

Next, with reference to FIGS. 4 to 6, a concrete operation example according to the above processing flow will be described. When image data (input image) as shown in FIG. 4A is input by the scanner 101, the connected component detection unit 201
First generates a binarized image as shown in FIG. 4 (b), detects connected components as shown by a rectangle in FIG. 4 (c),
Next, an image in which the size of the connected component is smaller than a certain value is extracted as a pattern, the feature amount of the extracted pattern is extracted, the pattern is recognized, and the feature amount and the position of the pattern are stored in the memory 202.

Then, the repeat extraction unit 203 causes the memory 20 to
5A based on the recognition result (feature amount and pattern position) of the connected component detection unit 201 stored in FIG.
, The number of appearances is a predetermined threshold (for example, 3
Only patterns that exceed the number of times) are extracted, and if they appear in a certain fixed cycle, it is determined that there is a repeating pattern. Specifically, for example, as shown in FIG. 5B, a histogram of the positional relationship of the patterns is created, and it is determined that there is repetition when the most frequent part is a predetermined threshold value (for example, 4) or more. Then, the corresponding pattern is recognized as a repeating pattern. Note that FIG. 5B shows an example in which a histogram is created based on the distance in the X direction between the patterns at the X and Y coordinates in FIG. 5A.

The copy-prohibited document discrimination control unit 204 determines the presence / absence of a repeating pattern based on the recognition result of the repeating extracting unit 203. If there is a repeating pattern, the image processing unit 1
The instruction to change the output state of the output image and the position of the repeating pattern are transferred to 02. Here, if, for example, an instruction to change the output state is issued from the copy-prohibited document discrimination control unit 204 for thinning output of the repeating pattern (that is, changing the appearance frequency), the image processing unit 102 outputs the repeating pattern. A plurality of repeating patterns are appropriately thinned according to the position and transferred to the printer 103. FIG. 6A shows the printer 1.
3 shows the output image output on the recording paper by 03. 6B shows a repeating pattern in which the pattern 601 is thinned out on the input image.

If the copy prohibited document discrimination control unit 204 instructs rotation and enlargement of the repeating pattern as an instruction to change the output state, the image processing unit 102 sets the repeating pattern in accordance with the position of the repeating pattern. It is rotated / enlarged and transferred to the printer 103. FIG. 7 shows an example of an output image obtained by rotating and enlarging the repeating pattern 701 and outputting it.

Further, if it is instructed by the copy inhibition document discrimination control unit 204 to change the hue of the repeating pattern as an instruction to change the output state, the image processing unit 102 causes the hue of the repeating pattern to be changed according to the position of the repeating pattern. And transfer to the printer 103. FIG. 8 shows a repeating pattern 801.
An example of an output image that is output by changing the hue of is shown.

As described above, in the first embodiment, attention is paid to the fact that a specific pattern repeatedly appears in a copy-inhibited document for which copying is legally prohibited, and a repeating pattern that repeatedly appears in the input document image. Is detected and the output state of the output image is changed according to the recognition result of the repeated pattern, so that it is possible to process many types of copy-protected original documents with an appropriate processing time and without increasing false detections and misjudgments. Discrimination processing can be performed. In addition, it is possible to perform many kinds of copy prohibited document discrimination processing without having to register a specific image in the copy prohibited document as pattern data.

Furthermore, since the output state of the output image is changed only by changing the output state of the repeating pattern, it is easy to see that the image output on the recording paper is a copy, unlike the original image. Since it does not affect the parts other than the repeated pattern, the risk of losing the information of the original image is reduced, and the original copy can be sufficiently used.

[Embodiment 2] The embodiment 2 is equipped with a repeating pattern dictionary means (repeating pattern dictionary 906 described later) for storing the feature amount of the pattern recognized as the repeating pattern, and a predetermined pattern is input from the input original image. When a pattern satisfying the condition is detected, the feature amount used for recognizing the repeated pattern is extracted from the pattern, the repeated pattern recognition process is performed using the extracted feature amount, and the recognized repeated pattern is recognized. When the feature quantity that matches the feature quantity is not stored in the repeating pattern dictionary means, the feature quantity of the corresponding repeating pattern is stored in the repeating pattern dictionary means.

Further, when the feature amount matching the feature amount extracted from the pattern satisfying the predetermined condition is stored in the repetitive pattern dictionary means, the repetitive pattern is recognized in the repetitive pattern recognition process for the corresponding pattern. The recognition condition is changed so that the pattern can be easily recognized.

The basic structure of the second embodiment is common to that of the first embodiment, and only different parts will be described here.

FIG. 9 is a copy prohibition manuscript discrimination section 9 of the second embodiment.
01 configuration, a connected component detection unit 902, a memory 903 for storing the feature amount of the connected component extracted by the connected component detection unit 902 and its position (address), and a connected component detection unit 902 After the extraction, referring to the feature amount and the position of the connected component stored in the memory 903, a repeating pattern for extracting (recognizing) a repeating pattern repeatedly appearing at a constant cycle from all the extracted connected components Extraction unit 904, copy prohibition document discrimination control unit 905 that changes the output state of the output image according to the detection result of the repeated pattern extracted by the repeated extraction unit 904, and the characteristics of the pattern recognized as the repeated pattern And a repeating pattern dictionary 906 for storing quantities.

Here, when the feature amount matching the recognized feature amount of the repeat pattern is not stored in the repeat pattern dictionary 906, the repeat extracting unit 904 determines the feature amount of the repeat pattern as the repeat pattern. This is a configuration to be stored in the dictionary 906.

Further, the connected component detecting section 902, when the feature amount matching the feature amount extracted from the pattern satisfying the predetermined condition is stored in the repeated pattern dictionary 906,
This is a configuration in which the recognition condition of the repeated pattern for the corresponding pattern, which is used in the process of the repeated extraction unit 904 in the next stage, is changed to a condition that makes it easy to recognize the repeated pattern.

The operation of the above configuration will be described. FIG. 10 shows a processing flow of the second embodiment. The processing flow of the second embodiment is basically the same as the processing flow of the first embodiment shown in FIG. 3, and common reference numerals indicate the same processing. Therefore, different parts will be described in detail.

The copy-prohibited document discriminating unit 901 detects the connected component (S303), and extracts an image in which the connected component has a size smaller than a certain value (condition value of preset repeating pattern) as a pattern (S304). ).

Subsequently, by extracting the feature amount of the extracted pattern, the pattern is recognized, and when the feature amount matching the extracted feature amount is stored in the repetitive pattern dictionary 906, the repetitive extraction is performed. The unit 904 is instructed to change the recognition condition of the repeated pattern for the corresponding pattern (S1001).

S303 and S30 for all connected components
4, when the processes of S1001 and S306 are completed, the repetitive extraction unit 904 refers to the feature amount and the position of the pattern stored in the memory 903, and the same pattern appears a predetermined number of times (threshold value) or more, and When it appears in a certain fixed period, it is extracted as a repeating pattern. However, in this case, for a pattern in which the instruction to change the recognition condition of the repeated pattern is input from the connected component detection unit 902, the number of times of the threshold value, which is one of the recognition conditions, is reduced to form a repeated pattern. Change to conditions that are easily extracted (S100
2).

When the extraction of the repeating pattern by the repeating extraction unit 904 is completed, the copy-prohibited document discrimination control unit 905 determines the presence or absence of the repeating pattern based on the extraction result (recognition result) of the repeating extraction unit 904. If there is a repeating pattern (S308), the feature amount of the corresponding pattern is stored in the repeating pattern dictionary 906, and the image processing unit 102 is instructed to change the output state of the output image and the position of the repeating pattern ( Address) is transferred (S1003). However, the feature amount of the corresponding repeating pattern is already in the repeating pattern dictionary 906.
If it is stored in, the image processing unit 102 is only instructed to change the output state of the output image and transfers the position (address) of the repeating pattern.

When the image processing unit 102 receives the instruction to change the output state of the output image and the position of the repeating pattern, it corrects the image of the repeating pattern and transfers it to the printer 103 (S309). If an instruction to change the output image is input, the output image is transferred to the printer 103 after performing normal image processing.

The printer 103 outputs the image data input from the image processing unit 102 onto the recording paper (S310).

Next, with reference to FIG. 11, a specific operation example according to the above processing flow will be described. When image data (input image) as shown in FIG. 11A is input by the scanner 101, the connected component detection unit 902
First generates a binarized image as shown in FIG. 11 (b), detects a connected component as shown by a rectangle in FIG. 11 (c), and then determines the size of the connected component to a certain value. A smaller image is extracted as a pattern, the feature amount of the extracted pattern is extracted, the pattern is recognized, and a comparison determination is made as to whether or not the feature amount that matches the extracted feature amount is stored in the repetitive pattern dictionary 906. If the feature amount that matches the feature amount of the shaded rectangle shown in FIG. 11D is stored in the repeat pattern dictionary 906, the repeat pattern recognition condition for the corresponding pattern is changed. The repeat extraction unit 904 is instructed to do so.

Thereafter, the repeat extraction unit 905 causes the memory 20
5A based on the recognition result (feature amount and pattern position) of the connected component detection unit 201 stored in FIG.
As shown in, the number of appearances is a predetermined threshold (for example,
Only patterns that exceed 3 times) are extracted, and if they appear in a certain fixed period, it is determined that there is a repeating pattern. Specifically, for example, as shown in FIG. 5B, a histogram of the positional relationship of the patterns is created, and it is determined that there is repetition when the most frequent part is a predetermined threshold value (for example, 4) or more. Then, the corresponding pattern is recognized as a repeating pattern.

However, in this case, the connected component detecting section 90
For the pattern in which the instruction to change the recognition condition of the repeated pattern is input from 2, the threshold of the number of appearances, which is the recognition condition, is reduced to 3 → 2, and the threshold of the frequency of the histogram is reduced to 4 → 3. Then, the condition is changed to a condition in which the corresponding pattern is easily extracted as a repeated pattern.

As described above, in the second embodiment, in addition to the effect of the first embodiment, the pattern which is recognized as the repeated pattern even once by the copy-prohibited document discrimination unit 901 is
The feature quantity of the pattern is stored so that it can be easily recognized as a repeating pattern when the corresponding pattern is extracted in the subsequent processing. Therefore, for a document having an image recognized as the repeating pattern, Thus, the learning effect can improve the discrimination accuracy.

[Third Embodiment] In the third embodiment, in the same configuration as the second embodiment, the feature quantity extracted from the pattern (connected component) satisfying a predetermined condition by the connected component detection unit 902 and the feature quantity that matches the feature quantity When the pattern is stored in the repeat pattern dictionary 906, the corresponding pattern is recognized as a repeat pattern, and the copy prohibiting document discrimination control unit 905 is notified via the repeat extracting unit 904.

The operation of the above configuration will be described. FIG. 12 shows a processing flow of the third embodiment. Note that the processing flow of the third embodiment is basically the same as the processing flow of the first embodiment shown in FIG. 3, and common reference numerals indicate the same processing. Therefore, different parts will be described in detail.

The copy-prohibited document discriminating unit 901 detects a connected component (S303), and extracts an image whose connected component has a size smaller than a certain value (condition value of a preset repeating pattern) as a pattern (S304). ).

Subsequently, by extracting the feature amount of the extracted pattern, the pattern is recognized, and if the feature amount matching the extracted feature amount is stored in the repeating pattern dictionary 906, the corresponding pattern is detected. Is notified to the repeat extraction unit 904 (S1201).

S303 and S30 for all connected components
4, when the processing of S1201 and S306 is completed, the repetitive extraction unit 904 refers to the feature amount and the position of the pattern stored in the memory 903, the same pattern appears a predetermined number of times (threshold value) or more, and When it appears in a certain fixed period, it is extracted as a repeating pattern. However, at this time, if there is a pattern notified from the connected component detection unit 902 that the pattern is a repeating pattern, the corresponding pattern is recognized as a repeating pattern, and the position of the corresponding pattern is extracted ( S1202).

When the extraction of the repeating pattern by the repeating extraction unit 904 is completed, the copy-prohibited document discrimination control unit 905 determines the presence or absence of the repeating pattern based on the extraction result (recognition result) of the repeating extraction unit 904. If there is a repeating pattern (S308), the feature amount of the corresponding pattern is stored in the repeating pattern dictionary 906, and the image processing unit 102 is instructed to change the output state of the output image and the position of the repeating pattern ( Address) is transferred (S1203). However, the feature amount of the corresponding repeating pattern is already in the repeating pattern dictionary 906.
If it is stored in, the image processing unit 102 is only instructed to change the output state of the output image and transfers the position (address) of the repeating pattern.

When the image processing unit 102 receives the instruction to change the output state of the output image and the position of the repeating pattern, the image processing unit 102 corrects the image of the repeating pattern and transfers it to the printer 103 (S309). If an instruction to change the output image is input, the output image is transferred to the printer 103 after performing normal image processing.

The printer 103 outputs the image data input from the image processing unit 102 on the recording paper (S310).

As described above, in the third embodiment, in addition to the effect of the first embodiment, regarding the pattern recognized as the repeated pattern even once in the copy-prohibited document discrimination unit 901,
The feature amount of the pattern is stored, and in a subsequent process, when the corresponding pattern is extracted, the pattern is recognized as a repeating pattern. Therefore, the learning effect is applied to a document having an image recognized as the repeating pattern. With this, it is possible to improve the discrimination accuracy.

In the first to third embodiments described above, when the repeating pattern is recognized, the copy-prohibited document discriminating unit 104 notifies the system controller 106 that the copy-prohibited document is present, and the operation display unit is displayed. You may make it display a message etc. via 105.

[0065]

As described above, the image forming apparatus of the present invention responds to the repeated pattern recognition means for recognizing the repeated pattern repeatedly appearing in the input document image and the recognition result of the repeated pattern recognition means. In addition, since the output image changing means for changing the output state of the output image is provided, it is possible to perform a lot of types of copy inhibition document discrimination processing in an appropriate processing time and without increasing erroneous detection / misidentification. You can

Further, when a pattern satisfying a predetermined condition is detected from the input original image, the repetitive pattern recognition means extracts a feature amount used for recognizing the repetitive pattern from the pattern and uses the extracted feature amount. Since the repeated pattern recognition process is performed in this manner, it is possible to perform many types of copy prohibited document discrimination processing without the need to register a specific image in the copy prohibited document as pattern data.

Further, when the repeating pattern is recognized, the output image changing means changes the appearance frequency of the repeating pattern in the output image, or a part or all of the repeating pattern in the output image. The image output on the recording paper is different from the original image and is easily a copy because the image is deformed and / or rotated or the color tone of a part or the whole of the repeating pattern in the output image is changed. In addition, since it does not affect the parts other than the repeated pattern, the risk of losing the information of the original image is reduced, and the original copy can be sufficiently used.

Further, the image forming apparatus of the present invention recognizes the repeating pattern repeatedly appearing in the inputted original image, and the output pattern of the output image according to the recognition result of the repeating pattern recognizing means. Output pattern changing means for changing the output state and repeat pattern dictionary means for storing the feature amount of the pattern recognized as the repeat pattern by the repeat pattern recognizing means are provided. When a pattern satisfying a predetermined condition is detected from the input document image, the feature amount used for recognizing the repeating pattern is extracted from the pattern, and the repeating pattern recognition process is performed using the extracted feature amount. If the feature quantity that matches the recognized feature quantity of the repeat pattern is not stored in the repeat pattern dictionary means, the feature quantity of the repeat pattern is repeated. In order to be stored in turn dictionary means,
It is possible to perform many kinds of discrimination processing of copy-prohibited originals within an appropriate processing time without increasing erroneous detection and misjudgment, and it is necessary to register a specific image in the copy-prohibited originals as pattern data. Therefore, it is possible to perform the discrimination processing of many kinds of copy prohibited originals.

When the repeating pattern recognition means stores a characteristic amount matching the characteristic amount extracted from the pattern satisfying the predetermined condition in the repeating pattern dictionary means, the repeating pattern for the corresponding pattern is repeated. In the pattern recognition process, the recognition condition is changed so that it can be easily recognized as a repeating pattern, or the characteristic amount matching the characteristic amount extracted from the pattern satisfying the predetermined condition is stored in the repeating pattern dictionary means. If so, by recognizing the corresponding pattern as a repeating pattern,
The accuracy of discrimination can be improved by the learning effect with respect to a document having an image recognized as a repeating pattern.

[Brief description of drawings]

FIG. 1 is an explanatory diagram illustrating a schematic configuration of a color digital copying machine that is an image forming apparatus according to a first exemplary embodiment.

FIG. 2 is an explanatory diagram illustrating a configuration of a copy-prohibited document determination unit according to the first exemplary embodiment.

FIG. 3 is an explanatory diagram showing a processing flow of the first embodiment.

FIG. 4 is an explanatory diagram showing a specific operation example according to the processing flow of FIG.

5 is an explanatory diagram showing a specific operation example according to the processing flow of FIG.

FIG. 6 is an explanatory diagram showing a specific operation example according to the processing flow of FIG.

FIG. 7 is an explanatory diagram showing an example of an output image obtained by rotating, enlarging and outputting a repeating pattern.

FIG. 8 is an explanatory diagram showing an example of an output image output by changing the tint of the repeating pattern.

FIG. 9 is an explanatory diagram showing a configuration of a copy-prohibited document discrimination unit according to the second embodiment.

FIG. 10 is an explanatory diagram showing a processing flow of the second embodiment.

11 is an explanatory diagram showing a specific operation example according to the processing flow of FIG.

FIG. 12 is an explanatory diagram showing a processing flow of the third embodiment.

[Explanation of symbols]

 101 Scanner 102 Image Processing Unit 103 Printer 104 Copy Prohibited Document Discrimination Unit 105 Operation Display Unit 106 System Controller 201 Connected Component Detection Unit 202 Memory 203 Repeat Extraction Unit 204 Copy Prohibited Document Discrimination Control Unit 901 Copy Prohibited Document Discrimination Unit 902 Connected Component Detection Part 903 Memory 904 Repeat extraction part 905 Copy prohibited document discrimination control part 906 Repeat pattern dictionary

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Midori Aida Inc. 1-3-6 Nakamagome, Ota-ku, Tokyo Stock company Ricoh Co., Ltd. (72) In Hitoshi Nakamura 1-3-6 Nakamagome, Ota-ku, Tokyo Stock Company Ricoh

Claims (8)

[Claims] 1. An image forming apparatus having a copy-prohibited document discrimination function for discriminating whether or not an inputted document image is a document image for which copying is prohibited, and a repeating pattern repeatedly appearing in the inputted document image. And an output image changing means for changing the output state of the output image according to the recognition result of the repeating pattern recognizing means. 2. The repetitive pattern recognition means, when a pattern satisfying a predetermined condition is detected from the input document image, extracts a feature amount used for recognizing the repetitive pattern from the pattern and extracts the feature amount. The image forming apparatus according to claim 1, wherein the repeating pattern recognition process is performed using the feature amount. 3. An image forming apparatus having a copy-prohibited document discrimination function for discriminating whether or not the inputted document image is a document image for which copying is prohibited, and a repeating pattern repeatedly appearing in the inputted document image. Of the repeating pattern recognition means, the output image changing means for changing the output state of the output image according to the recognition result of the repeating pattern recognition means, and the repeating pattern recognition means for recognizing the repeating pattern. Repeating pattern dictionary means for storing the feature amount of the pattern, the repeating pattern recognizing means recognizes the repeating pattern when a pattern satisfying a predetermined condition is detected from the input document image. The feature amount to be used is extracted from the pattern, the repeated pattern recognition process is performed using the extracted feature amount, and the feature amount is the same as the recognized feature amount of the repeated pattern. An image forming apparatus characterized in that, when the amount is not stored in the repeating pattern dictionary means, the characteristic amount of the repeating pattern is stored in the repeating pattern dictionary means. 4. The repetitive pattern recognizing means, when a feature quantity matching a feature quantity extracted from a pattern satisfying the predetermined condition is stored in the repetitive pattern dictionary means, repeats the corresponding pattern. 4. The image forming apparatus according to claim 3, wherein in the pattern recognition processing, the recognition condition is changed so that the pattern can be easily recognized as a repeated pattern. 5. The repeating pattern recognizing means repeats the corresponding pattern when a characteristic quantity matching the characteristic quantity extracted from the pattern satisfying the predetermined condition is stored in the repeating pattern dictionary means. The image forming apparatus according to claim 3, wherein the image forming apparatus recognizes the pattern. 6. The output image changing means changes the frequency of appearance of the repeating pattern in the output image when the repeating pattern is recognized. Alternatively, the image forming apparatus according to item 5. 7. The output image changing means deforms or / and rotates a part or all of the repeating pattern in the output image when the repeating pattern is recognized. , 2, 3, 4 or 5
The image forming apparatus described. 8. The output image changing means changes the color tone of a part or all of the repeating pattern in the output image when the repeating pattern is recognized. , 2, 3, 4 or 5, the image forming apparatus.