JP2003078745A - Image processor, image forming device provided with the image processor, image processing method, computer program for executing this image processing method, and computer-readable recording medium for recording the computer program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image processor that can enhance the security performance even by avoiding data processing of digital data such as image data from being complicated. SOLUTION: An area separation section 9 separates input image data into a plurality of areas including a character area, a dot area and a photographing area. A data processing section 10 attaches an area identification signal being a result of the area separation to the input image data as a code in response to attribute data of the image data. Thus, so long as the attached code is not eliminated in decoding image data, the image data cannot properly be decoded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus, an image forming apparatus provided with this image processing apparatus, an image processing method, a computer program for executing this image processing method, and a recording medium recording this computer program. Pertain to. In particular, the present invention relates to improvement of a data management method for making it difficult to illegally decode image data.

[0002]

2. Description of the Related Art In recent years, digital devices such as digital copying machines and scanners, and computers typified by personal computers have rapidly become popular. And
A network environment in which these devices are communicatively connected to each other via a communication line such as a LAN cable is being prepared. As a result, the user can easily digitize and send various kinds of information and can store the information in a server or the like on the network so that the information can be shared by a plurality of users. It has become to.

However, since the digital information is easily duplicated, it is necessary to take sufficient security measures against leakage of the digital information as the information is digitized and shared as described above. Is coming. For example, there is an increasing need to take measures to prevent a situation in which image data stored in a server on a network is illegally viewed by an unauthorized third party.

As one of such data security measures, for example, a data management device disclosed in Japanese Patent Laid-Open No. 2000-172566 has been proposed. In this publication, for data management of, for example, a personal computer, image data is separated into a data body and its attribute information, and these are individually stored in a storage unit. Further, a technique is disclosed in which management information for managing the two pieces of separated information is stored in the management unit as an address separate from the storage unit. For example, with respect to electronic data of a GIF image composed of a header, a logical screen descriptor, and an image descriptor, the header and the logical screen descriptor are used as attribute information, and the image descriptor is stored in the storage unit as a data body. In addition, the association information is stored in the management unit as management information. When the image data is restored, the attribute information and the data body are combined and restored based on the management information stored in the management unit.

[0005]

However, in the data management method disclosed in the above publication, electronic data (image data) is separated into a data body and its attribute information, and the management information is further stored. Since it is necessary to save each individually, it is inevitable that the processing operation becomes complicated. Also, since the data body and the attribute information are stored without being subjected to data modification processing, it is possible to restore electronic data by combining various attribute information in the data body in order. was there. For this reason, it cannot be said that the data is in a data management state where security is sufficiently ensured.

The present invention has been made in view of the above circumstances, and an object thereof is to improve security while avoiding complication of data processing operation for digital data such as image data. An image processing apparatus capable of achieving the above, an image forming apparatus including the image processing apparatus,
An object is to provide an image processing method, a computer program for executing the image processing method, and a recording medium recording the computer program.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention separates input image data into a plurality of regions according to the type of the image, and separates these image data. , A code corresponding to each attribute data is added. As a result, at the time of decoding the image data, appropriate decoding cannot be performed unless only the added code is removed.

-Solution Means-Specifically, the present invention is premised on an image processing apparatus for storing and managing input image data. By inserting a predetermined additional code into the input image data to the image processing apparatus and creating the additional code and the input image data as a series of data, illegal decoding of the image data is prevented. Decryption blocking means is provided.

As the code added by the decoding preventing means, a code corresponding to the attribute data of the image data (attributes such as a character area, a halftone dot area, a photograph area) is adopted.

As a concrete structure of the decoding preventing means, an area separating means for separating the input image data into a plurality of areas including a character area, a halftone dot area, and a photograph area, and an area separating means for separating the area are provided. Data processing means for adding the resulting area identification signal to the input image data as a code corresponding to the attribute data of the image data is provided.

By encoding the input image data according to these specific items, the original image data is managed in a changed state. Therefore, even if an attempt is made to illegally decode this image data, proper decoding cannot be performed unless only the added code is removed.
As a result, the image data can be managed with high security. Further, since the input image data can be handled as one data without being divided into the main body data and the attribute data, the data processing operation is not complicated.

As a specific configuration of the data processing means, area extracting means for extracting an area having a large amount of information based on the result of area separation by the area separating means, and the area separating means for the extracted input image data. Editing means for encoding and adding the outputted area identification signal is provided.

As described above, by processing an area having a large amount of information, the main data in the input image data can be efficiently encoded and stored, and the security of the main part of the image data can be secured. It is possible to improve the sex especially.

Further, the data processing means is provided with a random number generating means for transmitting a random number signal. And the editing means
A region identification signal is encoded and added to a pixel selected based on the random number signal transmitted from the random number generation unit, for the region having a large amount of information extracted by the region extraction unit.

According to this, although it is possible to add the area identification signal to the entire area, it is possible to randomly select pixels to be subjected to processing such as change to the input image data by using random numbers. It is efficient.

Based on the additional level control signal for setting the ratio of the pixels to which the code is added to the input image data, the editing means uses the random number signal transmitted from the random number generating means to select each at a constant ratio. When the area identification signal is encoded and added to the pixel, the addition level control signal can be used to change the degree to which the area identification signal is added according to the importance of the input image data. Become.

The following structure is provided as an image forming apparatus that can be provided with a copy prohibiting function for a copy prohibited document by using the above image processing apparatus. That is, image input means for reading the input image data, pattern recognition means for determining whether or not a predetermined pattern is present in the input image data, and any one of the above image processing devices, An image output unit that forms an image on the recording medium using a visible color material based on the output image data output from the image processing apparatus is provided.

With this specific item, it is possible to perform processing such that the image quality of the output image is remarkably deteriorated when a predetermined pattern is present, or much information contained in the image is lost. Is. In this case, as the means for lowering the image quality, the above-mentioned encoding means by area separation is used. Thereby, for example, it is possible to provide an image forming apparatus having a copy prohibition function of a copy prohibition document.

Further, as another image forming apparatus, the following constitutions are listed. That is, an image input unit that reads input image data, one of the above image processing devices, a communication unit that transmits and receives data to and from an external device via a communication line, and the image processing device An image output unit for forming an image on the recording medium by using a visible color material based on the output image data output is provided.

By this specific matter, it becomes possible to encode the input image data by using, for example, a digital copying machine and transmit the data to a target server or the like via the communication means.

As an image processing method performed by the image processing apparatus, a predetermined additional code is inserted into the input image data, and the additional code and the input image data are created as a series of data to obtain an image. A decryption blocking operation is performed to prevent unauthorized decryption of data. This makes it possible to easily encode and store the input image data as one data without dividing it.

In the above image processing method, an area separation process for separating input image data into a plurality of areas including a character area, a halftone dot area, and a photograph area, and an area identification signal as a result of the area separation processing are attributed to image data. Data processing for adding to the input image data as a code according to the data, and in this data processing, an additional code signal transmitting operation for transmitting an additional code signal indicating whether to add the area identification signal to the input image data is performed. ing. This eliminates the need to add the area identification signal to all the pixels, so that the increase in the image data amount due to the encoding can be suppressed.

The additional code signal is compressed by run-length coding and stored. As a result, it is possible to suppress an increase in the image data amount due to the generation of the additional code signal.

When the position to which the area identification signal is added is made variable by the additional position signal generated from the additional code signal, the position of the added code is not uniform.
Therefore, it becomes more difficult for a third party to modify the image data, and the security of the image data can be further enhanced.

Further, the following processing operations are listed when the image data is restored. That is, when restoring the image data to which the area identification signal is added, if the password for specifying the user is different from the one used when the image data was encoded, the image data is output randomly. To Therefore, when the password is different from the predetermined password, the image data is randomly stored in the output line buffer when the image is output. When the image data is exchanged and output for each plane, it may be easy to visually recognize in the case of a character area. However, according to the present invention, the randomness of the image when output is high, Image recognition by a person becomes difficult.

A computer program for causing a computer to execute any one of the above image processing methods and a recording medium having the computer program recorded so that the computer can read the computer program are also within the scope of the technical idea of the present invention. .

With the above computer program, it is possible to cause a computer to execute an image processing method capable of easily encoding and storing input image data as one data without dividing it. Moreover, the versatility of the image processing method can be enhanced by the recording medium.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is a block diagram showing the arrangement of a color image processing apparatus 1 according to this embodiment when applied to a computer system.

As shown in FIG. 1, a color image input device 2 and a color image output device 3 are connected to the color image processing device 1. Examples of the color image input device 2 include a flatbed scanner and a digital camera. In addition, this color image input device 2
Sends image data read as analog signals of RGB (R: red, G: green, B: blue) to the color image processing apparatus 1. On the other hand, examples of the color image output device 3 include a liquid crystal display and the like.

-Description of Configuration of Color Image Processing Device 1- The color image processing device 1 is provided with a storage unit 5. The storage unit 5 is, for example, a hard disk for storing image data, a magneto-optical storage medium such as MO, a CD-R.
W (Compact Disc Rewritable) and DVD (Digital Ver
optical storage media such as satile Disc).

Further, the color image processing apparatus 1 has an A / D
The (analog / digital) conversion unit 6, the shading correction unit 7, the input gradation correction unit 8, the area separation processing unit 9, the data processing unit 10, the color correction unit 12, the spatial filter processing unit 13, and the output gradation correction unit 14 are provided. I have it. Further, it also includes a control unit 4 that integrally controls these units, the color image input device 2 and the color image output device 3.

The image data decomposed into RGB which is input from the color image input device 2 is converted into a digital signal in the A / D converter 6. Shading correction unit 7
Then, processing for removing distortion of various signals generated in the illumination system, the imaging system, and the imaging system of the color image input device 2 is performed. The input tone correction unit 8 removes the data of the area corresponding to the background with a histogram or the like before performing the area separation processing in the area separation processing unit 9 described later, and then the RGB reflectance signal is color-balanced. And at the same time perform processing to convert signals such as density signals into signals that the image processing system can easily handle.
This image data is transmitted to the area separation processing section 9. As the processing for the background area in this case, for example, a prescan is performed to create a histogram of the input image data and the density value (or density classification) having the highest frequency in the low density area is used as the background area. Be seen. As a result, the image data in which only the data of the background area is removed is created, and this image data (character area, halftone dot area, and photographic area data) is transmitted to the area separation processing unit 9.

Then, the area separation processing section 9 uses the input image data to determine to which area among the character area, the halftone dot area and the photograph area each pixel belongs by the area separation processing. , The area identification signal 11 to be added to the data of each pixel is created corresponding to the data of each pixel. Then, the area identification signal 11 is output from the area separation processing section 9 to each processing section 10, 12, 13 such as the color correction section 12 and the spatial filter processing section 13. This constitutes the decryption blocking means in the present invention.

In the image data input to the color correction unit 12, RGB signals are converted into R'G'B 'signals corresponding to the output characteristics of the color image output device 3 in order to realize faithful color reproduction. It In the spatial filter processing unit 13, a spatial filter process for preventing blurring of an output image and deterioration of graininess is performed by a digital filter that corrects the spatial frequency characteristic. The output gradation correction unit 14 performs an output gradation correction process for adjusting the gradation of a signal such as a density signal according to the characteristics of the color image output device 3. In this way, the image data sequentially processed by each processing unit is transmitted to the color image output device 3.

Next, the configuration of the data processing unit 10 is shown in FIG.
Will be explained. The data processing unit 10 includes a counting unit 1
6, a comparison unit 17 and an editing unit 18 are provided. Counting unit 1
In 6, the number of pixels in each area is counted for each of the R, G, and B planes based on the area identification signal 11 created by the area separation processing section 9. The comparing unit 17 extracts a region having a large amount of image information (having a large number of pixels) by comparing the total value of the number of pixels of each plane for each region. And
In the editing unit 18, either the processing for each pixel data is not performed, or the processing for adding the code (the code based on the area identification signal 11) to each pixel data of the extracted image area is performed. Be seen. At this time, when the area with a large amount of image information is different for each plane (for example, a color character, a halftone dot composed of a single color, etc.), the area to which the code is added may be changed for each plane. This information is temporarily stored in the storage unit 5 and is referred to when performing a code addition process described later. Further, the image data to which the above-mentioned code is added is transmitted to the storage unit 5 and recorded as one set of data.

FIG. 3 is a flow chart showing the processing operation when encoding is performed in the data processing unit 10 shown in FIG. The encoding processing operation will be described below.

First, in step S1, when the image data is read, it is determined according to an instruction displayed on the color image output device 3 by using an interface (not shown) whether or not the encoding is performed. In this case, in this instruction screen, the image area (character
It may be possible to specify a photograph area). If the encoding is not performed, the process proceeds to step S6, and the read image data is stored in the storage unit 5 as it is.

On the other hand, when encoding is executed (step S
If YES in 1), the password is input and saved in step S2. This password may be stored together with the image data as a password for starting the encoding process, or may be stored in a storage area different from the image data. This password is required in the decryption process described later.

In step S3, the area separation processing section 9 separates the input image data into image areas. Next, in step S4, a region with a large amount of image information is extracted by adding the region separation result for each region. Then, in step S5, the area identification signal 11 is added to the upper bits of the data of each pixel in the extracted image area. The image data subjected to the data processing in this manner is stored in the storage unit 5 in step S6.

The operation of adding the area identification signal 11 will be described in detail below. FIG. 4 is an example of a part of data using the area identification signal 11 as a code to be added.
If each image area is classified into three areas of a character area, a halftone dot area, and a photograph area, the area identification signal 1 for one pixel
The image identification code that is 1 can be represented by 2-bit information in which two "0" s or "1" s are arranged. For example, by setting the character area to “01”, the halftone area to “10”, and the photograph area to “11”, the image identification code can be added for each classification of each image area. That is, FIG.
As shown in (A), the image information at each pixel point originally has an 8-bit information amount which is an array of eight "1" s or "0" s. ), A 2-bit image identification code (area identification signal "10" in FIG. 4) is added to form 10-bit information as a series of data.

The code to be added may be added to the lower bits instead of the upper bits. Further, the position of the added bit may be changed according to each of the R, G, and B planes. For example, in the R / B plane, the code is added to the upper bits,
A sign may be added to the lower bits in the G plane. The image data to which the image identification code is added in this way is stored in the storage unit 5 and referred to when decoding.

Even if the encoded image data is output to the color image output device 3 as it is, the original image data is changed by the area identification signal 11 in this case, and hence the original image data is changed. An image that is completely different from an image, that is, an image that does not make sense. Further, since the encoded image data is digital information, it is easy to copy, but even if it is simply copied, it is possible to change the position of the code added to each plane as described above. The information regarding the above-mentioned encoding is, for example, FIG.
The area identification signal 1 inserted in the original image data is stored in the header portion of the data as shown in
It is not easy to remove 1 and high security can be secured.

Next, the operation of decoding the image data encoded as described above will be described. Figure 5
7 is a flowchart showing a processing operation when the data processing unit 10 performs decoding.

In the case of decryption, first, in step S7, the password used at the time of encoding is input based on the information on the selection screen displayed on the image output device 3. In step S8, if the input password is the same as the encoded password, the process proceeds to step S9 for decryption. On the other hand, if a different password is input, the data stored in the storage unit 5 in step S11 is directly output to the image output device 3. That is, the image data that has not been appropriately decoded is output to the image output device 3. Instead of this, the plane data may be replaced and read (for example, when the R plane data is read, the B plane information is read). This also allows the image data to be output without being properly decoded.

As described above, when the data stored in the storage unit 5 is output as it is, the area identification signal 11 is unknown, the data is also changed, and the data is read at random, and after the color correction processing. Since no regular processing is performed, an image different from the original image is output.
Further, at this time, the editing unit 18 may replace the data with “0” or “255” for the area having a large amount of information (image data to which the area identification signal is added) and output the data.

On the other hand, if the password input in step S8 is the same as the encoded password, that is, if YES, the process proceeds to the decoding process operation in step S9 and thereafter. In step S9, the editing unit 18 reads the information and the image data stored in the storage unit 5 to which the code is added, and the data is extracted by associating the number of bits of the information corresponding to each pixel with each plane. Align.
In the above example, the lower 8 bits are extracted in the R / B plane, and the upper 8 bits are extracted in the G plane. By this operation, the area identification signal 11 inserted in the original image data is removed, and the original image data is obtained. Then, the image data thus decoded is output to the area separation processing unit 9 in step S10. As a result, normal image processing is performed on the image data, and this image data is output to the color image output device 3.

According to the image data processing operation of the present embodiment, by encoding the input image data, it is possible to make it difficult to illegally decode the image data, and at the same time, to convert the input image data into the main body data and the attribute data. It is convenient because it can be handled as one data without being divided.

Furthermore, by using the above-described area separation processing method, the input image data can be easily encoded and stored as one data without being divided. Such a region separation processing method is a technique that is generally used as one of image processing methods, and the OCR (Optical Ch
The present invention can be realized without requiring dedicated software or hardware typified by aracter Reader) and is highly practical.

(Second Embodiment) Next, a second embodiment of the present invention will be described. In this embodiment, the configuration of the data processing unit 10 and its processing operation are different from those of the first embodiment described above. Therefore, only the differences from the first embodiment will be described here. In addition, the same reference numerals are given to members that are substantially the same as the constituent members in the first embodiment,
The description is omitted.

FIG. 6 shows the data processing unit 10 in this embodiment.
3 is a block diagram showing the configuration of FIG. As a feature of the data processing unit 10, a random number generator 20 is provided, and
It is mentioned that the additional level control signal 21 is transmitted to the editing unit 18. In this embodiment, the rank corresponding to the importance of the input image to be read, which is shown as the additional level control signal 21 in FIG. 6, is used to control the number of pixels to which the area identification signal 11 is added. It has become. In this case, to which pixel the area identification signal 11 is actually added is determined by using the random number transmitted from the random number generator 20. For example, in the case of a rank 1 input image that means the most important,
The area identification signal 11 is added to about 80% or more of the total number of pixels in the image area, and rank 2 meaning important
In the case of the input image of
The area identification signal 11 is added to about 80% or less of the pixels, and in the case of the rank 3 input image meaning normal (default), the number of pixels is about 50 to less than 60% of the total number of pixels in the image area. A configuration in which an identification signal is added can be considered. It is convenient if the additional level control signal 21 can be interactively selected in accordance with the instruction screen of the color image output device 3, as shown below. Also in this case, the position of the code to be added (upper bit / lower bit) may be changed for each plane.

As a specific operation in the data processing section 10, first, the counting section 16 counts the number of pixels in each area on the basis of the area identification signal 11 generated by the area separation processing section 9 and compares them. The unit 17 compares the total value of the number of pixels of each plane for each area. As a result, a region having a large amount of image information (having a large number of pixels) is extracted.
Then, the editing unit 18 does not process each pixel data, or uses the signal (random number) from the random number generator 20 and the additional level control signal 21 to select the plane of the extracted image area. One of the processing operations is performed by adding a predetermined code to the data of all the pixels.

As the random number generator 20, for example, a configuration in which a password is used as a seed of random number generation and a pseudo uniform random number is generated can be considered. Also, by changing the threshold value for the generated pseudo-uniform random number according to the rank of the additional level control signal 21, it becomes possible to randomly select pixels to which a code is added at a constant rate. In this case, the identification signal is not the area identification signal of the image area but simply “10”.
2-bit data such as may be fixed and used. Then, the image data to which the above code is added is sent to the storage unit 5 and recorded as one set of data.

FIG. 7 is a flow chart showing the processing operation at the time of encoding in the data processing unit 10 shown in FIG. First, in step S12, the flag F1 representing the ranking of the coding corresponding to the additional level control signal 21 is set to the default value "3". In step S13, when the image data is read,
According to the instruction displayed on the color image output device 3, whether or not to encode is determined using an interface (not shown). If not, go to step S22
The read image data is stored in the storage unit 5 as it is.

On the other hand, when encoding, step S1
At 4, the password is entered and saved. This password may be stored together with the image data as a password for starting the encoding process, or may be stored in a storage area different from the image data.

Next, in step S15, it is determined according to the instruction screen of the color image output device 3 whether or not to rank the coding. If the ranking is not performed, the flag F1 for encoding remains the default value "3" set in step S12. If ranking is to be performed, the value of the flag F1 for encoding ("1" or "2") is selected in step S16.

Next, in step S17, it is selected in the instruction screen whether or not an image area (character / photo area, etc.) to which an identification signal (code) is added is designated. or,
In this case, it is possible to select an operation of extracting a region having a lot of image information. If no area is designated, it is assumed that all areas have been selected and the process proceeds to step S23.

Next, step S1 when the area is designated
In 8, it is determined whether or not the value of the encoding ranking is "3". If this value is "3", the process proceeds to step S19, and a random number is generated based on the default value. It On the other hand, if this value is not "3", the process proceeds to step S20, and a random number is generated based on the selected level. In the next step S21, a sign is added to the upper bits of the data of the pixels selected at a constant rate, to the image data of the designated image area based on the generated random numbers. The image data processed in this way is
It is stored in the storage unit 5 in step S22.

Step S Assume that All Areas are Selected
In 23, it is determined whether or not the value of the encoding ranking is "3". If the value is "3", the process proceeds to step S24, and a random number is generated based on the default value. It On the other hand, if this value is not "3", the process proceeds to step S25, and a random number is generated based on the selected level. In the next step S26, based on the generated random numbers, the image data of the entire image area for each plane is
A code is added to the upper bits of the data of the pixels selected at a constant rate. The image data subjected to the data processing in this way is stored in the storage unit 5 in step S22.

In the case of this embodiment, the code to be added may be added to the lower bits instead of the upper bits. Also, R ・ G ・
The position of the bit to be added may be changed in each plane of B. For example, in the R / B plane, the code may be added to the upper bits, and in the G plane, the code may be added to the lower bits. This information is stored in the storage unit 5 and is referred to when performing coding.

Regarding the decoding of the image data, the storage unit 5
The information and image data added with the code stored in is read, and the number of bits of information corresponding to each pixel is made to correspond to each plane so that the data is extracted and aligned. This is the same as the case described using the flowchart of FIG. 5 in one embodiment.

In the present embodiment, it is possible to add the identification signal to the whole area in the first place, but as in the above-mentioned configuration, by using the random numbers, the pixels to be subjected to the processing such as the modification to the input image data are It is more efficient if it can be randomly selected.

(Third Embodiment) Next, a third embodiment of the present invention will be described. Also in this embodiment, members that are substantially the same as the constituent members in the first embodiment are given the same reference numerals, and descriptions thereof will be omitted.

FIG. 8 is a block diagram showing the arrangement of the color image processing apparatus 1 according to this embodiment. In this embodiment, the pattern recognition unit includes a pattern storage unit 30 that stores a pattern indicating a copy-inhibited document in advance and a pattern recognition unit 31 that collates the patterns. As described below, by using the two, for example,
It has become possible to provide a digital copying machine having a copy prohibition function for copy prohibited originals.

In FIG. 8, the color image input device (image input means) 2 comprises, for example, a scanner unit, and R
Image data read by a CCD reading line sensor or the like as a GB analog signal is sent to the color image processing apparatus 1. The color image processing apparatus 1 converts the RGB-decomposed image data input from the image input apparatus 2 into a digital signal in the A / D conversion unit 6, and the shading correction unit 7 in the illumination system of the image input apparatus. A process for removing various distortions generated in the image forming system and the image pickup system is performed, and the input tone correction unit 8 further removes the data of the region corresponding to the background in the histogram or the like, and then the reflectance signals of RGB are
At the same time as adjusting the color balance, it performs processing to convert signals such as density signals into signals that are easy for the image processing system to handle.
The image data is sent to the pattern recognition unit 31. In this case, as the processing for the background area, as in the case described above, prescan is performed to create a histogram of the input image data, and the density value (or density classification) having the maximum frequency in the low density area is set as the background area. And it is sufficient.

In the pattern recognition section 31 to which the data is input from the input gradation correction section 8, the pattern storage section 30 is previously stored.
Patterns indicating copy-protected originals stored in
Character patterns such as CONFIDENTIAL) and the input image data are used for pattern matching. As the pattern matching method, for example, the brightness difference method is used. In this method, for all pixels of the pattern stored in the pattern storage unit 30, the absolute value of the difference between the stored pattern data at each pixel position and the read image data is calculated and calculated. The absolute value is calculated using the sum of all pixels as an index, and the stored pattern is moved in 1-pixel units in the horizontal and vertical directions with respect to the read image data. Judgment is made based on the result.

As a result of the pattern recognition, the pattern storage unit 30
When the pattern indicating the copy-inhibited document stored in No. 3 is not detected, the pattern recognition unit 31 sends the image data as it is to the area separation processing unit 9. On the other hand, when the pattern indicating the copy-inhibited document is detected, the image data is sent to the area separation processing unit 9 in this case as well, but in this case, another processing is performed in the data processing unit 10 described later. Be seen.

The area separation processing section 9 uses the input image data to determine to which area of the character area, the halftone dot area, and the photographic area each pixel belongs by the area separation method.
The area identification signal 11 is generated. Generated area identification signal 1
1 is sent to each unit that performs subsequent processing. The image data that has been subjected to the region separation processing is sent to the next data processing unit 10.

In the data processing unit 10, the area separation processing unit 9
The input data is processed by the operation described later and sent to the color correction unit 12 or the color image output device 3.

The image data input to the color correction unit 12 is
CMY containing unnecessary absorption components to achieve faithful color reproduction
(C: Cyan, M: Magenta, Y: Yellow) A process for removing color turbidity based on the spectral characteristics of the color material is performed, and in the next black generation undercolor removal unit 32, from the CMY three-color signals after color correction. Black generation for generating a black (K) signal, processing for subtracting the K signal obtained by black generation from the original CMY signal to generate a new CMY signal are performed, and CMY three-color signals are CMYK.
Are converted into four color signals. Subsequent spatial filter processing unit 13
In the above, the spatial filter processing is performed by the digital filter for correcting the spatial frequency characteristic so as to prevent blurring of the output image and deterioration of graininess.

Then, the output gradation correction unit 14 performs an output gradation correction process for converting a signal such as a density signal into a halftone dot area ratio which is a characteristic value of the color image output device 3, and finally a gradation is obtained. The reproduction processing unit 15 performs gradation reproduction processing (halftone generation) in which the image is divided into pixels and processed so that the respective gradations can be reproduced.

The image area determined to be a character area by the area separation processing unit 9 has a high-frequency emphasis amount by a sharpness emphasis process in the spatial filter process in order to enhance the reproducibility of black characters or color characters in particular. Be made bigger. At the same time, the gradation reproduction processing section 15 selects binarization or multi-value conversion processing on a high resolution screen suitable for reproduction of high frequencies. On the other hand, the area determined by the area separation processing unit 9 as a halftone dot is subjected to appropriate processing such as low-pass filter processing for removing moire. Further, the area separation processing unit 9 performs binarization or multi-value processing on the screen, which places importance on gradation reproducibility, for the image area determined to be the photograph area. The image data that has been subjected to each of the processes described above is temporarily stored in a storage unit (not shown), read at a predetermined timing, and output to the color image output device (image output unit) 3.

FIG. 9 is a block diagram showing the configuration of the data processing unit 10 in this embodiment. In the data processing unit 10, the area separation processing unit 9 is used by using the input image data.
Based on the area identification signal 11 generated by the above, first, the counting unit 16 counts the number of pixels of each area for each of the R, G, and B planes, and then the comparison unit 17 calculates the total number of pixels of each plane for each area. Compare the values. As a result, a region having a large amount of image information (having a large number of pixels) is extracted. Then, the editing unit 18 does nothing, or adds a code to the data of each pixel of the extracted image area, or does not add a code, and the data of the area having a large amount of information is all 0 or 255. Edit to replace with, and output the data. Also at this time, when the area having a large amount of image information is different for each plane, the area to which the code is added may be changed for each plane.

In the data processing unit 10, the area separation processing unit 9
The input data is subjected to the following processing operation according to the flowchart of FIG. 10 and sent to the color correction unit 12 or the image output device 3.

In step S27, the pattern recognition unit 31
If the pattern indicating the copy-inhibited document is not detected in step 1, the procedure ends, and the data processing unit 10 outputs the input data as it is to the color correction unit 12.
On the other hand, when the pattern indicating the copy prohibited document is detected, the following operation is performed. In step S28, the area separation processing unit 9 separates each image area using the input image data. Next, in step S29, the counting unit 16 of the data processing unit 10 counts the number of pixels in each region for each plane, and the comparing unit 17 compares the number of pixels to obtain a region with a large amount of image information (a large number of pixels). To extract. In step S30, the editing unit 1
In 8, editing is performed by adding a code to the data of each pixel of the extracted image area or by replacing all the data in the area having a large amount of information with 0 without adding a code, and outputting the data as an image. Send to device 3.

Examples of the image output device 3 include a device for outputting image data on a recording medium (for example, paper) such as a color image output device using an electrophotographic system or an inkjet system. It is not particularly limited.

According to the above configuration, only when a predetermined pattern is recognized, the image quality of the output image is remarkably deteriorated, and much of the information contained in the document is lost. It is possible to provide a digital copying machine having a function for a copy-protected document.

(Fourth Embodiment) Next, a fourth embodiment of the present invention will be described. In this embodiment, the random number generator 20 is provided in the data processing unit 10 as in the second embodiment. The configuration other than the data processing unit 10 in this embodiment is the same as that of the third embodiment described above.
Therefore, only the configuration of the data processing unit 10 will be described here. Moreover, the ranking with respect to the importance considered in the second embodiment is not considered here.

FIG. 11 is a block diagram showing the configuration of the data processing unit 10 in this embodiment. FIG. 11 and the third
A difference from FIG. 9 showing the configuration of the data processing unit 10 in the embodiment is that a random number generator 20 is provided.

In the data processing unit 10, the area separation processing unit 9
Based on the area identification signal 11 generated by the above, first, the counting unit 16 counts the number of pixels in each area for each plane, and then the comparing unit 17 compares the total number of pixels in each area for each area. A region with a large amount of image information (a large number of pixels) is extracted by. Then, in the editing unit 18, nothing is done or the random number generator 2 according to the random number generation control signal 40 is applied to each pixel of the extracted image area.
Based on a random number generated by using 0, pixels are selected at a fixed rate and a code is added to the upper bits of the data of the selected pixel, or all the data is 0 without adding a code or It is edited whether or not it is replaced with 255, and the data is output. Also in this case, when the area having a large amount of image information is different for each plane, the area to which the code is added may be changed for each plane.

In the present embodiment, the data processing unit 10
Is subjected to the following processing operation according to the flowchart of FIG. 12 and is sent to the color correction unit 12 or the image output device 3.

In step S31, when the pattern recognition section 31 does not detect the pattern indicating the copy-inhibited document, the data processing section 10 outputs the input data as it is to the color correction section 12. On the other hand, if the pattern indicating the copy prohibited document is detected, the process proceeds to step S32, and the following operation is performed. Step S3
In 2, the area separation processing unit 9 separates each image area using the input image data. Next, in step S33, the counting unit 16 counts the number of pixels in each area for each plane, and the comparing unit 17 compares the total number of pixels in each plane for each area to obtain a large amount of image information (the number of pixels Extract many areas. In step S34, the editing unit 18 adds a code to the data of each pixel of the extracted image area based on the random number generated by the random number generator 20, or does not add the code. 0 or 2 for all data in areas with a large amount of information
Editing to replace with 55 is performed, and the data is sent to the color image output device 3.

In the present embodiment as well, it is possible to add the identification signal to the entire area in the first place. However, by using the random numbers as in the above configuration, the pixels to be subjected to the processing such as modification to the input image data are selected. It is more efficient if it can be randomly selected.

Further, as another example of the third and fourth embodiments implemented as a digital copying machine, for example, a digital copying machine is used as a scanner and image data is encoded and transmitted to a personal computer or a server. Can also be applied to. As such an example, the following fifth embodiment can be considered.

(Fifth Embodiment) FIG. 13 is a block diagram showing the arrangement of a color image processing apparatus 1 according to the fifth embodiment. The image processing method in the case of this embodiment is substantially the same as that of the previous embodiment. The image data is stored in the storage unit 5, and then transmitted from the communication unit 50 to a target device such as the personal computer 51.

According to the above configuration, for example, input image data can be encoded by using a digital copying machine, and the data can be sent to a target server or the like via a communication means, which is convenient.

(Sixth Embodiment) Next, a sixth embodiment will be described. In this embodiment, the code to be added is controlled to reduce the data amount. In the present embodiment, the configuration of the data processing unit 10 is substantially the same as that of the second embodiment, as shown in FIG. 14, but the data processing content is different.

In the data processing unit 10 according to this embodiment, an additional code signal indicating whether or not the area identification signal 11 is added is generated based on the random number signal from the random number generator 20 and the additional level control signal 21. As shown in FIG. 15B, this means that the pixels to which the area identification signal 11 is added are set to "1" and the pixels not to be added are set to "0", and signals are generated for all the pixels. ), The area identification signal 11 is added only to the pixels for which the additional code signal is "1".
Is added, and the additional code signal is run-length encoded and stored in the storage unit 5 together with the image data to which the area identification signal 11 is added.

The run-length coding method is used for coding a binary signal, and is for coding the run (length) of "0" or "1".
For example, when the additional code signal is “11100100”, run-length coding is performed on this signal to give “1110110”. The code word length of the run length code is arranged before the run length code, as typified by Weil encoding.
Further, the position to be added to the area identification signal 11 may be changed to upper bits and lower bits for each pixel as shown in the following description (for the run length coding method and the Weil coding, see, for example, Japanese Patent Laid-Open Publication No. Hei 5- See Japanese Patent No. 336378).

FIG. 16 shows the data processing unit 10 shown in FIG.
3 is a flowchart showing the flow of processing when encoding is performed.

First, in step S111, the flag F1 representing the ranking of the coding corresponding to the additional level control signal 21 is set to the default value "0".

When the image data is read in step S112, according to the instruction displayed on the color image output device (not shown), using the interface (not shown),
Decide whether to encode or not. When not encoded, the read image data is stored in the storage unit 5 as it is.

In the case of encoding, the password is entered and saved in step S113. The password may be saved together with the image data as a password for starting the encoding process, or may be saved in a storage area different from the image data.

Next, in step S114, it is determined whether or not encoding is to be ranked according to an instruction screen (not shown). If the ranking is not performed, the flag F1 for encoding remains the default value "0" set in the first step S111. If ranking is to be performed, the value of the flag F1 for encoding is selected in step S115.

Next, in step S116, it is selected on the instruction screen whether or not the image area (character / photo area, etc.) to which the area identification signal 11 (code) is added is designated. In this case, it is also possible to select an operation of extracting a region having a large amount of image information. If it is selected, the process proceeds to step S117. If no region is designated, it is assumed that all regions are selected, and the process proceeds to step S122. It should be noted that the following processes from this point on are only the difference in whether or not an area has been selected, so the explanation will be made assuming that no area has been selected, that is, all areas have been selected.

Next, it is determined that all areas are selected. In step S122, it is determined whether or not the coding ranking value is "0". If it is "0", the process proceeds to step S123. A random number is generated based on the default value, and if it is not "0", the process proceeds to step S124, and a random number is generated based on the selected level.

In the next step S125, an additional code signal is generated based on the generated random number. This is
As shown in (b), it indicates whether or not the area identification signal 11 is added for each pixel. The pixel to be added is "1", and the pixel not to be added is "0". The additional code signal thus generated becomes a bit string for the number of pixels forming the image data.

Further, in step S126, step S1
Based on the random number generated in step S23 or step S124, as shown in FIG. 15A, the additional code signal is added to the upper bits of the image data only in the pixel of "1". As a result, the image information of each pixel point in the original image has an 8-bit information amount, which is an array of eight 1s or 0s, but in this embodiment, it is generated as shown in FIG. By adding a 2-bit image identification code according to a random number, 10-bit and 8-bit pixel information is mixed.

In step S127, as shown in FIG. 15B, the additional code signal generated in S125 is run-length coded to reduce the data amount. The image data and the additional code signal thus data-processed are stored in the storage unit 5 in step S128.

Further, the security accuracy can be further improved by randomly setting the position to which the area identification signal 11 is added. FIG. 17 is a flowchart showing the flow of the processing.

First, in step S201, initial values of an additional position signal and an additional code signal representing a position to be added are set. The additional position signal may be set to "1" when the area identification signal 11 is added to the upper bits of the image data, "0" when added to the lower bits, and the initial value may be set to "1". Further, the difference D between the additional code signals between a certain pixel of interest D _n and the pixel D _n-1 immediately before it is calculated. In addition,
At the pixel (for example, the pixel at the upper left corner of the image) from which this processing is started, there is no previous pixel, and at this time, D = 0.

[0102] proceeds to step S202 in the case of D ≧ 0, the position for adding the region identification signal 11 at the pixels of D _n is the same as the pixel D _n-1. That is, the additional position signal is set to "1". If D <0, step S203
To advances, the position for adding the region identification signal 11 at a pixel of D _n is the contrary to the position in the D _n-1 of the pixel, the adding position signal to "0".

The above processing is performed for each pixel, and the area identification signal 11 is added to the pixel in step S204 according to this addition position signal. FIG. 18 illustrates the above process.

Since this additional position signal can be calculated based on the additional code signal, it is not necessary to store it together with the image data, but it is possible to add the code randomly. When the random additional signal shown, for example, the random additional signal is "1", the image shown in FIG. 17 is processed and encoded, and when the random additional signal is "0", the process shown in FIG. 16 is executed. It is necessary to store the random additional signal in the header of the image data in the form of an encoded image.

FIG. 19 is a flow chart showing the flow of processing when decoding is performed in the data processing unit 10.

In the case of decoding, first, step S3
Based on the information on the selection screen displayed on the image output device 3 as 01, the password for encoding is input. In step S302, if the input password is the same as the encoded password, the process proceeds to step S303 for the next decryption, and if a different password is input, it is stored in the storage unit 5 in step S309. The stored data is output to the image output device as it is.
Alternatively, the plane data may be exchanged and read (for example, when the plane data of R is read, B is read).
Read the information of the plane).

In the case of decoding, the storage unit 5 in S303.
The run-length coded additional code signal is read from and is decoded.

In the next step S304, the random additional signal is read to read the coding state of the image data.

When the random addition signal is "0", that is, when the code is added to the upper or lower order in all the pixels, the image data is read from the storage unit 5 in the next step S307, and the additional code signal is added. The area identification signal 11 added based on the above is removed. That is, with respect to the pixel for which the additional code signal is "1", the area identification signal 11 is removed from the upper bits to obtain 8-bit data, and nothing is processed for the pixel for which the additional code signal is "0". Shall not be applied.

When the random addition signal is "1", that is, when the code is randomly added to the upper and lower sides by the pixel, the addition position signal is generated based on the addition code signal in step S305, and this addition is performed. According to the position signal and the additional code signal, the image data is read from the storage unit 5 in step S306 and the added area identification signal 11 is removed.

After the number of bits of each pixel is adjusted in this way, the image data is output to the area separation processing section 9 in step S308.

According to the above configuration, even if the 10-bit pixel to which the area identification signal 11 is added and the 8-bit pixel to which the area identification signal 11 is not added are mixed in the image data subjected to the encoding process, By using the code signal, the code can be removed only from the pixels to which the area identification signal 11 is added, the increase in the image data amount due to the code addition can be suppressed, and the data after the encoding can be suppressed. Can increase the randomness of.

In each of the above-described embodiments, when the decryption password is different from the encoding password at the time of decryption, whether or not the encoded password is output to the image output device. Alternatively, as described above, the plain data is read and output, but it may be read randomly using random numbers as described below.

FIG. 20 is a flow chart showing the flow of the processing. Note that this flowchart is the processing content when the password is incorrect in the flowchart shown in FIG. 19 (S309 in FIG. 19).

First, in step S401, a random number is generated. In the next step S402, the generated random number value is added to or subtracted from the pixel value. This makes the pixel value more random (this process is not always necessary).

In step S403, the image output device 3
Image data is randomly stored in a line buffer as shown in FIG. Normally, the pixel values are stored in order from the line buffer, but for example, the pixel values are stored in the order of the line buffer. In this state, the image is output to the image output device 3.

By performing the above processing, it is possible to maintain a high security accuracy even in a character portion which is relatively easy to visually recognize even when the planes are replaced and output.

(Seventh Embodiment) Next, a seventh embodiment will be described. The present embodiment relates to a computer-readable computer program for executing the image processing method according to each of the above-described embodiments, and a recording medium storing this computer program.

When the above-described data processing method is recorded on the computer-readable recording medium in which the computer program to be executed by the computer is recorded as described above, the recording medium in which the computer program for data processing is recorded can be carried easily. Can be provided.

In this embodiment, the recording medium may be a program medium such as a memory, for example, a ROM, or a computer program reading device may be provided as an external storage device.
It may be a program medium that can be read by inserting a recording medium therein.

In any case, the stored computer program may be configured to be accessed and executed by a microprocessor, or in any case, the computer program is read and the read computer program is Alternatively, the computer program may be downloaded to a computer program storage area (not shown) of the microcomputer and the computer program may be executed. It is assumed that the computer program for downloading is stored in the main body device in advance.

Here, the program medium is a recording medium that can be separated from the main body, and is a tape system such as a magnetic tape or a cassette tape, or a floppy (registered trademark).
Magnetic disks such as disks and hard disks, and CD-Rs
Disk systems for optical disks such as OM / MO / MD / DVD, card systems such as IC cards (including memory cards) / optical cards, mask ROM, EPROM (Erasab
le Programmable Read Only Memory), EEPROM (E
lectrically Erasable Programmable Read Only Memor
It may be a medium that fixedly carries a computer program, including a semiconductor memory such as y) or a flash ROM.

Further, in the present embodiment, since the system configuration is such that a communication network including the Internet can be connected, even a medium carrying the computer program fluidly so as to download the computer program from the communication network may be used. Good. When downloading a computer program from a communication network in this way, the computer program for downloading may be stored in the main unit in advance, or
Alternatively, it may be installed from another recording medium.

The above-mentioned image processing method (data processing method) is executed by reading the recording medium with a computer program reading device provided in a digital color image forming apparatus or a computer system. In particular, in the latter computer system, this image processing method can be used according to the preference of the user.

The computer system includes an image input device such as a flatbed scanner, a film scanner, and a digital camera, a computer on which various processes such as the above image processing method are performed by loading a predetermined computer program, and a processing result of the computer. It is composed of an image display device such as a CRT display and a liquid crystal display for displaying, and a printer for outputting the processing result of the computer onto paper or the like. Further, a modem or the like is provided as a communication means for connecting to a server or the like via a network.

When the present image processing method is executed by this computer system, the image area to which the identification signal is added and the level (importance rank) to which the identification signal is added as described above.
It becomes easy to arbitrarily change the setting of, and it is possible to perform processing according to the user's preference such as setting again according to the result displayed on the image display device.

With such a structure, the image processing method and the structure of the image forming apparatus become versatile.

[0128]

As described above, according to the present invention, a predetermined additional code is inserted into the input image data, and the additional code and the input image data are created as a series of data. It tries to prevent unauthorized decryption. Therefore, the original image data can be managed in a changed state, and even if the image data is illegally decoded, proper decoding cannot be performed unless only the added code is removed. As a result, the image data can be managed with high security.
Further, since the input image data can be handled as one data without being divided into the main body data and the attribute data, the data processing operation is not complicated.

Further, in the case where the area identification signal is coded and added to the image pixel selected based on the random number signal in the area having a large amount of information, the pixel to be subjected to the processing such as modification to the input image data. Can be randomly selected, and the security of the main part of the image data can be particularly enhanced.

Further, when the image formation is executed while judging whether or not a predetermined pattern is present in the input image data, the image formation having the copy inhibition function of the copy inhibited original document or the like. A device can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration when a color image processing apparatus according to a first embodiment is applied to a computer system.

FIG. 2 is a block diagram showing a configuration of a data processing unit in the first embodiment.

FIG. 3 is a flow chart showing a processing operation when encoding is performed in the first embodiment.

FIG. 4 is a diagram showing an example of a part of data using an area identification signal.

FIG. 5 is a flowchart showing a processing operation when performing decoding in the first embodiment.

FIG. 6 is a view corresponding to FIG. 2 in the second embodiment.

FIG. 7 is a view corresponding to FIG. 3 in the second embodiment.

FIG. 8 is a view corresponding to FIG. 1 in the third embodiment.

FIG. 9 is a view corresponding to FIG. 2 in the third embodiment.

FIG. 10 is a view corresponding to FIG. 3 in the third embodiment.

FIG. 11 is a view corresponding to FIG. 2 in the fourth embodiment.

FIG. 12 is a view corresponding to FIG. 3 in the fourth embodiment.

FIG. 13 is a view corresponding to FIG. 1 in the fifth embodiment.

FIG. 14 is a view corresponding to FIG. 2 in the sixth embodiment.

FIG. 15 is a diagram showing an example of part of data to which an area identification signal is added.

FIG. 16 is a view corresponding to FIG. 3 in the sixth embodiment.

FIG. 17 is a flowchart showing the encoding processing operation in the sixth embodiment.

FIG. 18 is a diagram showing an example of an additional position signal in the sixth embodiment.

FIG. 19 is a view corresponding to FIG. 5 in the sixth embodiment.

FIG. 20 is a flowchart showing a data storage operation in a line buffer in the sixth embodiment.

FIG. 21 is a diagram showing a line buffer in a decoding process.

[Explanation of symbols]

1 Color image processor 2 Color image input device 3 color image output device 9 area separation processing unit (area separation means) 10 Data processing unit (data processing means) 11 Area identification signal 17 Comparison means (area extraction means) 18 editorial department (editing means) 20 Random number generator (random number generating means) 21 Additional level control signal 30 pattern storage unit (pattern recognition means) 31 Pattern recognition unit 50 Communication unit (communication means)

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G06T 7/40 100 G06T 7/40 100C 5C063 H04N 1/419 5C076 H04N 1/40 1/40 F 5C077 1 / 419 Z 5C078 7/08 7/13 Z 5L096 7/081 7/08 Z 7/24 B41J 29/00 ZF term (reference) 2C061 AP01 AP04 AQ05 AQ06 CL08 2C087 AA09 AA13 AA16 AB05 AC07 AC08 BA01 BA03 BA05 BB10 DA14 5B017 AA03 AA06 BA07 BA10 CA16 5B057 AA11 CA01 CA08 CA12 CA16 CB01 CB08 CB12 CB16 CC01 CE06 CE08 CE16 CG04 5C059 KK43 ME05 RC40 SS12 SS20 UA02 UA39 5C063 PP07 PP01 PP07 5A19 PP08 PP14 5A19 PP08 PP14 5 PQ22 RR01 RR21 TT06 5C078 AA09 BA22 BA64 CA14 CA47 DB19 EA01 EA08 5L096 AA02 AA06 BA08 DA01 DA05 EA24 FA43 FA44 FA45 GA40

Claims (15)

[Claims] 1. An image processing apparatus for storing and managing input image data, wherein a predetermined additional code is inserted into the input image data, and the additional code and the input image data are created as a series of data. Accordingly, the image processing apparatus is provided with a decryption blocking unit that blocks unauthorized decoding of the image data. 2. The image processing apparatus according to claim 1, wherein the additional code is a code according to attribute data of the image data. 3. The image processing apparatus according to claim 1, wherein the decoding prevention means separates the input image data into a plurality of areas including a character area, a halftone dot area, and a photograph area, and An image processing apparatus comprising: a data processing unit that adds a region identification signal, which is a result of region separation by the region separation unit, to input image data as a code corresponding to attribute data of image data. 4. The image processing apparatus according to claim 3, wherein the data processing means extracts area having a large amount of information based on the result of area separation by the area separating means, and the extracted input image. An image processing apparatus comprising: an editing unit that encodes and adds a region identification signal output from the region separating unit to data. 5. The image processing device according to claim 4, wherein the data processing means includes a random number generating means for transmitting a random number signal, and the editing means is for an area having a large amount of information extracted by the area extracting means. On the other hand, the image processing apparatus is configured to encode and add the area identification signal to the image pixel selected based on the random number signal transmitted from the random number generating means. 6. The image processing apparatus according to claim 5, wherein the editing means outputs a random number from the random number generating means based on an additional level control signal for setting a ratio of pixels to which a code is added to the input image data. An image processing apparatus configured to encode and add a region identification signal to each pixel selected at a constant rate using a signal. 7. An image input means for reading input image data, a pattern recognition means for determining whether or not a predetermined pattern is present in the input image data, and any one of claims 1 to 6 above. One of the image processing devices, and an image output device that forms an image on a recording medium using a visible color material based on output image data output from the image processing device. Image forming apparatus. 8. An image input device for reading input image data, an image processing device according to claim 1, and data transmission / reception between an external device and a communication line. And an image output unit that forms an image on a recording medium by using a visible color material based on output image data output from the image processing apparatus. apparatus. 9. An image processing method for storing and managing input image data, wherein a predetermined additional code is inserted into the input image data and the additional code and the input image data are created as a series of data. By doing so, the image processing method is characterized in that the decoding preventing operation for preventing the illegal decoding of the image data is performed. 10. The image processing method according to claim 9, wherein the input image data is separated into a plurality of areas including a character area, a halftone dot area, and a photograph area, and an area resulting from the area separation processing. Data processing for adding the identification signal to the input image data as a code according to the attribute data of the image data, and in this data processing, an addition code signal indicating whether or not the area identification signal is added to the input image data An image processing method characterized by performing a code signal transmitting operation. 11. The image processing method according to claim 10, wherein the additional code signal is compressed by run-length coding and stored. 12. The image processing method according to claim 10, wherein the position to which the area identification signal is added is made variable by the additional position signal generated from the additional code signal. 13. The image processing method according to claim 9, wherein when the image data added with the area identification signal is restored, the password for identifying the user is the image data. An image processing method characterized by outputting image data at random when different from the coded one. 14. A computer program for causing a computer to execute the image processing method according to any one of claims 9 to 13. 15. A recording medium in which a computer program for executing the image processing method according to any one of claims 9 to 13 is recorded so as to be readable by a computer.