JP2001150742A - Apparatus and method for image processing and recording medium thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deterioration of an image and to embed access control information in the image. SOLUTION: A reference pattern vector is generated by a reference pattern vector generating section 210 and a pattern vector of an objective binary image is calculated by an observation pattern vector generating section 213. A correlation coefficient between the reference pattern vector and pattern vector of the objective binary image is calculated (214). A specific small amount space of the pattern vector of the objective binary image is moved (215) in such a manner that the calculated correlation coefficient is included in a predetermined range corresponding to each bit of the access control information added to the objective binary image. The objective binary image is changed to be printed based on the binary image which is moved in the specific small amount space (216). As a result, it is possible to print the image having the access control information embedded therein.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image processing apparatus and method for embedding access control information as watermark information in a document image or the like, and a storage medium for the method.

[0002]

2. Description of the Related Art In recent years, image quality formed by digital image forming apparatuses such as printers and copiers has been remarkably improved, and high quality images can be easily printed using these apparatuses. ing. Further, by reducing the price of high-performance scanners, printers, and copiers, and by performing image processing using computers, anyone can easily obtain desired printed matter. for that reason,
Problems such as unauthorized copying of printed matter (hereinafter, simply referred to as printed matter) such as documents, images, and photographs have been occurring. Therefore, in order to prevent or deter unauthorized use of a printed material due to such unauthorized copying, access control information as watermark information is embedded in the printed material.

[0003] As such an access control function, one that embeds access control information invisibly in a printed matter, and that embeds a bitmap pattern (glyph code, DD code, etc.) corresponding to the access control information in the margin of a document. In general, a document or a document image is subjected to scramble encryption. Among them, those that embed the access control information invisibly are, as general implementation methods, those that embed the access control information by controlling the amount of space in the English character string, those that rotate the characters and rotate the characters There is a method of embedding access control information in accordance with the above, and a method of enlarging or reducing a character and embedding the access control information in accordance with the enlargement or reduction ratio.

FIG. 21 is a diagram for explaining an example of embedding access control information by controlling the amount of space between words in an English character string. Here, reference numeral 1701 denotes a space between words. This space is p ← (1 + p) (p + s) / s s if the watermark bit to be embedded is “0”.
← (1-p) (p + s) / 2, and if the watermark bit is “1”, p ← (1-p) (p + s) / 2 s ←
(1 + p) (p + s).

FIGS. 22 and 23 show that a character is rotated.
FIG. 9 is a diagram illustrating an example of embedding access control information according to the amount of rotation. Here, FIG. 22 shows a state before the characters are rotated, and FIG. 23 shows a state after the characters are rotated. 1901 indicates the rotation angle θ of the character.

FIG. 24 is a diagram showing an example of embedding access control information by enlarging / reducing a character. Reference numeral 2001 denotes an original character width, and 2002 denotes a character width after reduction. Access control information is embedded according to enlargement / reduction.

[0007]

However, according to such an access control information embedding method, the original characters and images are obviously deformed, and the original characters and images are deteriorated. Will be.

Further, according to such an access control information embedding method, in order to accurately detect the embedded access control information, the printed matter is read with high accuracy and, for example, the space amount between words, The rotation angle of the character,
You need to read the size of the characters accurately. for that reason,
When printing is performed with a small character size and high resolution, there is a problem that it is very difficult to detect the access control information embedded in the printed matter.

SUMMARY OF THE INVENTION The present invention has been made in view of the above conventional example, and has as its object to provide an image processing apparatus capable of embedding access control information in an image without deteriorating the image, a method thereof, and a storage medium therefor. Aim.

It is another object of the present invention to provide an image processing apparatus and method capable of reading embedded access control information with high precision, and a storage medium for the method.

[0011]

In order to achieve the above object, an image processing apparatus according to the present invention has the following arrangement.
That is, an image processing apparatus for inputting and processing a binary image, comprising: calculating means for calculating a pattern vector of a target binary image; and a phase relationship between the pattern vector calculated by the calculating means and a reference pattern vector. Calculating means for calculating a number; input means for inputting access control information to be embedded in the target binary image; and the phase relationship calculated by the calculating means in accordance with the access control information input by the input means Moving means for moving the feature vector space of the pattern vector so that the number falls within a predetermined range; and changing means for changing the target binary image based on a result of moving the feature vector space. It is characterized by the following.

In order to achieve the above object, an image processing apparatus according to the present invention has the following arrangement. Extracting means for reading a document image and extracting a contour part of the image; means for obtaining a pattern vector of an image corresponding to the contour part; and a correlation coefficient between a pattern vector of a reference pattern and a pattern vector of the image. And a detecting means for detecting control information embedded in the document image according to the correlation coefficient obtained by the correlation coefficient calculating means. I do.

[0013] To achieve the above object, the image processing method of the present invention comprises the following steps. That is, an image processing method for inputting and processing a binary image, wherein a calculating step of calculating a pattern vector of a target binary image, and a phase relationship between the pattern vector calculated in the calculating step and a reference pattern vector A calculating step of calculating a number;
An input step of inputting access control information to be embedded in the value image, and, according to the access control information input in the input step, the correlation coefficient calculated in the calculation step is included in a predetermined range. A moving step of moving the feature vector space of the pattern vector; and a changing step of changing the target binary image based on a result of moving the feature vector space.

In order to achieve the above object, the image processing method of the present invention comprises the following steps. That is, an extraction step of reading a document image and extracting a contour part of the image, a step of obtaining a pattern vector of an image corresponding to the contour part, and a correlation coefficient between a pattern vector of a reference pattern and a pattern vector of the image. And a detection step of detecting control information embedded in the document image in accordance with the correlation coefficient obtained in the correlation coefficient calculation step. I do.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In the following embodiments, a monochrome laser beam printer (hereinafter, referred to as monochrome LBP) will be described as an example, but the present invention is not limited to this. Is also good. .

The document image is a binary black-and-white image.
An inexpensive scanner is used as an image reading device for reading printed matter.

[First Embodiment] FIG. 1 is a diagram showing a flow of conversion of monochrome LBP document image data related to embedding of access control information according to a first embodiment of the present invention.
In this figure, the image data of the document is binary image data 10.
1 is passed to the monochrome LBP printer driver. Next, the binary image data 101 is converted to binary data 102 of a device that matches the characteristics of each printer.
The multi-level K image data 103 is binarized into binary K image data 104.

The binary K image data 104 is passed to a printer engine and printed on paper or the like at a high resolution.

FIG. 2 is a diagram showing a flow of conversion of image data related to reading of access control information by the scanner according to the first embodiment of the present invention. In this figure, image data of a read document is transferred to a scanner driver as multi-valued grayscale image data 201.

Next, the observation pattern feature quantity space, reference vector, and reference pattern feature quantity space according to the present embodiment will be described.

FIG. 3 is a diagram showing an example of an image of M × N pixels corresponding to a part of the binary K image data 104.

FIG. 4 shows the outline of the image shown in FIG.
FIG. 4 is a diagram illustrating a contour image in which pixels are thinned.

FIG. 5 is a diagram showing a direction index index for extracting a feature amount of a date-ahead pixel when a target pixel is placed at the center of a 3 × 3 pixel block. In this figure, there are pixels in the t1, t2, t3, and t8 directions of the target pixel, and t4, t5,
The case where there is no pixel in the t6 and t7 directions is shown.

FIG. 6 shows the values of the direction index of the target pixel in FIG. 5 with respect to the feature amounts t1, t2, t3, t4, t5, t6, t7, and t8. Here, the value “1” indicates that there is a pixel in that direction, and “0” indicates that there is no pixel in that direction.

FIG. 7 shows the target pixel Pij of FIG. 5 shown in FIG.
Is a vectorized version of the direction index feature quantity.

Here, the direction index feature vector Hij is
The vector of the direction index feature amount of the pixel of interest Pij is shown. The number of dimensions of this vector is eight.

The observation pattern feature quantity space is a set of direction index feature quantity vectors for each pixel in the contour image obtained in FIG. The number of dimensions of the observation pattern feature quantity space is eight.

FIG. 8 shows a reference vector pattern. The reference vector of the reference vector pattern is a direction index feature amount of the pattern. FIG. 9 shows a vector DIST indicating the direction index special distribution amount. The number of dimensions of this vector is eight.

FIG. 10 is a diagram showing an example of a reference image of S × T pixels. FIG. 11 shows an outline image of the reference image. The reference pattern feature amount space is a direction index characteristic amount for each pixel in the outline image. It is a set of vectors. The number of dimensions of the reference pattern feature amount space is eight.

Next, a procedure for embedding access control information in a document image will be described.

FIG. 12 is a diagram showing an example of a bit sequence of access control information (watermark information). Here, 1
201 indicates a bit “0”, and 1202 indicates a bit “1”.

FIGS. 13 and 14 are flowcharts showing a process of embedding access control information (watermark information) for accessing the document image in the document image. Hereinafter, the operation will be described with reference to this flowchart.

First, in step S1, a reference vector (FIG. 9)
Reference pattern) and a reference pattern center vector are generated. Here, the reference pattern center vector (center) is obtained by the following equation (1).

Center = μ1 / √ (x1) Expression (1) Here, x1 is a variance vector of the reference pattern feature amount space, μ1 is an average vector of the reference pattern feature amount space, and “center” is a reference pattern. Is the center vector of.

Next, the process proceeds to step S2, where the binarization K of FIG.
A document image corresponding to the image data 104 is read. Next, the process proceeds to step S3, and as shown in FIG.
The document image read in step 2 is divided. In FIG.
Reference numeral 1601 denotes a block of M × N pixels, and 1602
Indicates the row number index of each block, and 1603 indicates the column number index of each block. In the figure,
The index number is an m × n matrix. Based on the index matrix, an index vector corresponding to each block of m × n dimensions is generated. At this time, the element number of the index vector becomes the index number of each block 1601.

Next, in step S4, a random number from "1" to "m * n" is generated based on key information determined in advance or input by the user. At this time, the generated random number corresponds to the element number of the index vector generated in step S3. That is, each random value corresponds to the index number of each block.

In step S5, for example, a bit sequence (8-bit data) of the access control information shown in FIG.
Is associated with the index number of each block. At this time, the correspondence is at the end of the bit sequence (in the example of FIG.
Bit), the association with the next block is
It starts from the head (first bit) of the bit sequence. In this way, this bit sequence is repeatedly allocated until each bit of the bit sequence is allocated to all blocks.

FIG. 16 shows a bit sequence 1 as watermark information.
FIG. 701 is a diagram illustrating a correspondence example between a random number sequence 1702 generated in step S4 and an index number of each block.

In FIG. 16, reference numeral 1701 denotes a bit sequence, and 1702 a random number sequence corresponding to the bit sequence. The number of bits of the bit sequence 1701 and the number of random numbers (R1 to Rmn) 1702 which are also index numbers of each block are both set. (M × n). In FIG. 16, the random number R1 corresponds to the block with the index number (I, J) = (1, 1), and the random number R2 is the index number (I, J) =
The last random number Rmn corresponds to the block of (1, 2), and similarly, the last random number Rmn is an index number (I, J) = (m, n)
Corresponds to the block.

Then, the process proceeds to a step S6, wherein the random number sequence 1702
The index number of the block (I, J = (1, 1)) corresponding to the X = 1st (the random number R1 in FIG. 16) and the value of the bit of the bit sequence 1701 corresponding to the index number (“0” in the example of FIG. 16) ") Is acquired (step S7). Then, the process proceeds to step S8, and the block of the M × N document image (the block of I = J = 1 in FIG. 15) corresponding to the obtained index number is obtained. Next, in step S9, an observation pattern vector is generated from the observation pattern center vector in the observation pattern feature amount space when the obtained M × N document image is used as the observation image, and the above-described reference vector. However,
The observation pattern center vector is given by the following equation (2).

Center = μ2 / √ (x2) Expression (2) Here, x2 is a variance vector in the observation pattern feature quantity space, μ2 is an average vector in the observation pattern feature quantity space, and “center” is an observation pattern. Is the center vector of.

Then, the process proceeds to step S10, where
The correlation coefficient (r) between the reference pattern vector generated in step 1 and the observation pattern vector generated in step S9 is calculated.

Then, the process proceeds to a step S11, where it is determined whether or not the bit of the bit sequence 1701 corresponding to the block is "0". If the bit is "0", the process proceeds to a step S12 so that -def <r <def The entire feature space of the observation pattern is moved.

In step S11, if the bit of the bit sequence 1701 corresponding to the block is "1", the process proceeds to step S14, where -1≤r≤-def or def≤r≤1, where "def" is , A predetermined value, and 0 ≦ def ≦ 1.

Here, step S12 and step S12
The movement of the feature space in 14 is performed in a direction in which the value of each element of all the feature vectors in the observation pattern feature space increases, and does not move in a direction in which the value of each element decreases.

Then, the process proceeds to step S13, where observed image data (document image) is reconstructed based on the feature space of the observed pattern after moving in the observed pattern feature space. In step S6, the process is performed until the random number sequence no longer exists, that is, until the process for the m × n-th random number (Rmn) is completed.

The binary K image data thus obtained is output to the printer engine as the binary K image data 104 in FIG. 1 and printed.

FIG. 17 is a block diagram showing a hardware configuration of the image processing apparatus according to the present embodiment.

In the figure, an input unit 110 for inputting image data is, for example, a scanner or a CD-R.
It is provided with a memory device or the like in which a storage medium such as an OM is mounted and image data stored therein is input. The image data may be loaded from an external storage device 115, which will be described later, or may be connected to a line interface (I / F) 11
7, and may be input from another network or the like. 111 is a CPU for controlling the operation of the entire apparatus.
The program executed by the CPU 111 (for example, shown in the flowcharts of FIGS. 13, 14, 18, and 19) is stored in the memory 112. Memory 112
Is used to temporarily store image data in the various processes described above, or to input / generate random numbers, vector information,
The CPU 111 stores index information and the like.
Is also used as a work area for storing various data at the time of processing. An input unit 113 includes a pointing device such as a keyboard and a mouse. The input unit 113 is operated by an operator and used to instruct generation of the above-described random number or to input various control information.

A display (display unit) 114 has, for example, a CRT, a liquid crystal, and the like. Reference numeral 115 denotes an external storage device that includes a storage medium such as a hard disk and an MO, and stores various image data and programs. Reference numeral 116 denotes a printer, which is an LBP in this embodiment as described above. However, the present invention is not limited to this, and may be, for example, a printer using an inkjet method. 11
A line interface unit 7 controls communication with another device or a network via a communication line.

Next, a case where access control information (watermark information) is extracted from an image in which a digital watermark is embedded as described above will be described.

FIGS. 18 and 19 are flowcharts showing a process for extracting the access control information from the image printed with the watermark information embedded therein. A program for executing this process is stored in the memory 112,
This is executed under the control of 11.

First, in step S21, a reference pattern vector is generated from the reference vector and the reference pattern center vector in the same manner as in step S1 of FIG. However, the reference pattern center vector is based on the above equation (1). Next, in step S22, the printed image is read in the gray scale mode (8 bits / pixel) using the scanner of the image input unit 110. Next, the process proceeds to step S23, where the outline of the read image is extracted,
For example, as shown in FIG. 4, a contour image in which the contour portion is thinned to one pixel is generated. Then, the process proceeds to step S24, where the contour image is converted into a size when the access control information is added. The following processing is performed on the converted contour image. The processing of steps S25 to S30 in FIGS. 18 and 19 is the same as that in FIGS.
Are basically the same as the processing of steps S3, S4, S6 to S9. However, it differs from step S7 in that step S28 extracts only the index number of the block corresponding to the X-th block in the random number sequence.

That is, first, in step S25, the aforementioned FIG.
As shown in FIG. 5, the contour image is divided into M × N blocks, and an m × n index matrix is generated from the row number index and column number index of each block. Then, an m × n-dimensional index vector is generated from the index matrix. Here, the element number of the index vector becomes the index number of each block.

Next, the process proceeds to step S26, where a random number of 1 to (m × n) is generated based on key information determined in advance or input by the user. At this time, the generated random number is based on the index generated in step S25.
Corresponds to the element number of the vector. That is, each random value is an index number of each block. Step S27
It is checked whether a random number sequence exists, that is, whether processing for all blocks has been completed.
Proceeding to 28, the index number of the block corresponding to X = 1st (R1) in the random number sequence is obtained. In step S29, an M × N contour image corresponding to the obtained block index number is obtained. Next, in step S30, an observation pattern vector is generated from the observation pattern center vector and the reference vector in the observation pattern feature space when the obtained M × N document image is used as the observation image. However, the observation pattern center vector is obtained by the above-described equation (2).

Then, the process proceeds to a step S31, wherein a correlation coefficient (r ') between the thus obtained reference pattern vector and the observed pattern vector is calculated. In step S32, the correlation coefficient (r ') is compared with a predetermined value. If -def <r'<def, the process proceeds to step S33, where it is determined that the embedded bit is "0", Otherwise, step S
Proceeding to 34, it is determined that the embedded bit is "1". Here, “def” is a preset value and 0 ≦ def ≦ 1. After executing step S33 or S34 in this manner, the process returns to step S27, and repeats the processing of steps S28 to S34 until the same processing is performed on the m × n-th random number (Rmn). A majority decision is made based on the bit sequence extracted in this way, and the bit length at the time of embedding is reproduced.

FIG. 20 is a functional block diagram showing a functional configuration of the image processing apparatus according to the present embodiment.

In the figure, reference numeral 210 denotes a reference pattern vector generation unit which generates a reference pattern generation vector based on the reference vector shown in FIG. 9 and, for example, the center vector of the reference pattern shown in FIG. Generate. 21
An input image dividing unit 1 divides an outline image (for example, FIG. 4) of an image read by a scanner or the like into a plurality of blocks, and represents each of the blocks by an index.
Each bit of the access control information input from the watermark bit input unit 212 is assigned to each block. 213
Is an observation pattern vector generation unit for an image block, which generates a vector of an observation pattern based on a center vector and a reference vector of an outline pattern (observation pattern) of an image block. Reference numeral 214 denotes a correlation coefficient calculation unit that calculates a correlation coefficient between the reference pattern vector obtained by the reference pattern vector generation unit 210 and the observation pattern vector obtained by the observation pattern vector generation unit 213. Reference numeral 215 denotes an observation pattern feature amount space moving unit which determines a value between the reference pattern vector and the inter-pattern pattern vector if the bit is “0” according to the value of the bit of the access control information embedded in the image block. Is moved in the feature amount space of the observed pattern so that the correlation coefficient r of (2) becomes (-def <r <def). If the bit is “1”, the feature pattern space of the observation pattern is moved so that the correlation coefficient r becomes (−1 ≦ r ≦ −def or def ≦ r ≦ 1). 2
Reference numeral 16 denotes a printing unit which prints an observation pattern (document image) changed based on the observation pattern vector to which the observation pattern feature amount space has been moved.

This is the flow of processing in a case where access control information is embedded in an input image and printing is performed.

When reading the document image printed in this way and extracting the access control information embedded therein, the input image dividing unit 211 reads the printed image and reads the outline of the image. A part is extracted, and the outline image is divided into a plurality of blocks. Then, an observation pattern vector generation unit 213 obtains an observation pattern vector of the image, and a correlation coefficient calculation unit 214 obtains a correlation coefficient r ′ between the observation pattern vector and the reference pattern vector. If the obtained correlation coefficient r ′ is −def <r ′ <def, the bit determination unit 217 determines that the bit embedded therein is “0”. It is determined that the embedded bit is “1”.

In this way, the access control information embedded in the image can be extracted.

As described above, according to the present embodiment, desired control information can be embedded without deteriorating an image.

Further, there is an effect that control information embedded in an image can be read and detected with high accuracy.

Even if the present invention is applied to a system including a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), a device including one device (for example, a copying machine, a facsimile machine, etc.) ) May be applied.

Further, an object of the present invention is to supply a storage medium (or a recording medium) recording a program code of software for realizing the functions of the above-described embodiments to a system or an apparatus, and to provide the system or the apparatus with the storage medium. It is also achieved by a computer (or CPU or MPU) reading and executing the program code stored in the storage medium. In this case, the program code itself read from the storage medium implements the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention. By executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an operating system (OS) running on the computer based on the instruction of the program code. This also includes a case where some or all of the actual processing is performed and the functions of the above-described embodiments are realized by the processing.

Further, after the program code read from the storage medium is written into the memory provided in the function expansion card inserted into the computer or the function expansion unit connected to the computer, the program code is read based on the instruction of the program code. This also includes the case where the CPU provided in the function expansion card or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

[0067]

As described above, according to the present invention, it is possible to embed access control information in an image without deterioration of the image.

According to the present invention, there is an effect that embedded access control information can be read with high accuracy.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a flow of conversion of document image data according to the present embodiment.

FIG. 2 is a diagram showing a flow of image data related to reading of access control information of a scanner.

FIG. 3 is a diagram illustrating an example of an observation image (document image) of M × N pixels.

FIG. 4 is a diagram illustrating an example of a contour image in which a contour portion of the observation image in FIG. 3 is indicated by one pixel.

FIG. 5 is a diagram illustrating a direction index feature amount of a pixel of interest.

FIG. 6 is a diagram showing a variation and a value of a direction index feature amount of a pixel of interest in FIG. 5;

7 is a diagram illustrating a variation of the direction index feature amount of FIG. 6 by a direction index feature amount vector.

FIG. 8 is a diagram illustrating an example of an image of a reference vector.

FIG. 9 is a diagram illustrating a direction index feature amount of the reference vector in FIG. 8;

FIG. 10 is a diagram showing an example of a reference image composed of S × T pixels.

11 is a diagram illustrating an example of a contour image in which the contour of the reference image in FIG. 10 is thinned to one pixel.

FIG. 12 is a diagram illustrating an example of a bit sequence of access control information.

FIG. 13 illustrates an image processing apparatus according to the present embodiment.
9 is a flowchart illustrating a process of embedding access control information in a document image.

FIG. 14 illustrates an image processing apparatus according to the present embodiment.
9 is a flowchart illustrating a process of embedding access control information in a document image.

FIG. 15 is a diagram illustrating an example in which a document image is divided into blocks.

16 is a diagram illustrating an example in which an access control information bit sequence and a random number sequence are assigned to each block divided in FIG.

FIG. 17 is a block diagram illustrating a hardware configuration of an image processing apparatus according to the present embodiment.

FIG. 18 is a flowchart illustrating a process of extracting, from a printed image, access control information in which the image is embedded.

FIG. 19 is a flowchart illustrating a process of extracting, from a printed image, access control information in which the image is embedded.

FIG. 20 is a functional block diagram illustrating a functional configuration of the image processing apparatus according to the present embodiment.

FIG. 21 is a diagram illustrating an example of embedding control information by controlling the amount of space between words.

FIG. 22 is a diagram illustrating a state before rotation of a character.

FIG. 23 is a view for explaining processing for embedding control information by rotating characters.

FIG. 24 is a diagram illustrating an example in which control information is embedded by enlarging / reducing characters.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2C087 AA13 BB10 BC02 BC05 CB06 CB13 DA13 5B021 LG08 LL01 5B057 AA11 BA02 BA29 CA02 CA06 CA12 CA17 CB02 CB06 CB12 CB17 CB19 CC03 CE08 CE09 CG07 DA08 DA17 DC02 DCA DCA BA06 9A001 BB02 BB03 GG05 HH23 HH34 JJ35 KK42 LL03

Claims (17)

[Claims] An image processing apparatus for inputting and processing a binary image, comprising: calculating means for calculating a pattern vector of a target binary image; and a pattern vector and a reference pattern vector calculated by the calculating means. Calculating means for calculating a correlation coefficient of; input means for inputting access control information to be embedded in the target binary image; and calculating means for calculating the correlation coefficient according to the access control information input by the input means. Moving means for moving the feature amount space of the pattern vector so that the correlation coefficient is included in a predetermined range; and changing means for changing the target binary image based on a result of moving the feature amount vector space An image processing apparatus comprising: 2. The calculating means includes: a contour extracting means for extracting a contour part of the target binary image; and a dividing means for dividing the contour part extracted by the contour extracting means into a plurality of blocks. The image processing apparatus according to claim 1, wherein a pattern vector of each of the plurality of blocks is calculated. 3. The moving means assigns each bit of the access control information input by the input means to each block divided by the dividing means, and when the bit is "0", the phase relation The number r satisfies −def <r <def, and when the bit is “1”, the correlation coefficient r is −1 ≦ r ≦ −def, or
3. The image processing apparatus according to claim 2, wherein the movement is performed such that def ≦ r ≦ 1. 4. The image processing apparatus according to claim 1, wherein the moving unit moves in a direction in which a value of each element of a feature amount vector of the target binary image increases. 5. The feature amount space is a set of vector information indicating whether or not a peripheral pixel of each pixel of the contour image of the target binary image exists. Item 2. The image processing device according to Item 1. 6. The image processing apparatus according to claim 1, further comprising a printing unit that prints based on image data corresponding to the target binary image changed by the changing unit. 7. Reading a document image formed based on the target binary image changed by the changing means,
Extracting means for extracting a contour part of the image; means for determining a pattern vector of an image corresponding to the contour part; determining a correlation coefficient between the reference pattern vector and the pattern vector by the calculating means; 2. The image processing apparatus according to claim 1, further comprising: detection means for detecting the access control information embedded in the document image according to the number. 8. An extracting means for reading a document image and extracting a contour part of the image, a means for obtaining a pattern vector of an image corresponding to the contour part, and extracting a pattern vector of a reference pattern and a pattern vector of the image. Correlation coefficient calculation means for obtaining a correlation coefficient, and detection means for detecting control information embedded in the document image according to the correlation coefficient obtained by the correlation coefficient calculation means An image processing apparatus characterized by the above-mentioned. 9. An image processing method for inputting and processing a binary image, comprising: a calculating step of calculating a pattern vector of a target binary image; and the pattern vector and the reference pattern vector calculated in the calculating step. A calculation step of calculating a correlation coefficient of: an input step of inputting access control information to be embedded in the target binary image; and a calculation step of calculating in accordance with the access control information input in the input step. A moving step of moving the feature amount space of the pattern vector so that the correlation coefficient is included in a predetermined range; and a changing step of changing the target binary image based on a result of moving the feature amount vector space. And an image processing method comprising: 10. The calculating step includes: a contour extracting step of extracting a contour part of the target binary image; and a dividing step of dividing the contour part extracted in the contour extracting step into a plurality of blocks. The image processing method according to claim 9, wherein a pattern vector of each of the plurality of blocks is calculated. 11. The moving step allocates each bit of the access control information input in the input step to each block divided in the dividing step, and when the bit is “0”, Number r is -d
ef <r <def, and when the bit is “1”, the correlation coefficient r is −1 ≦ r ≦ −def or def ≦ r ≦
The image processing method according to claim 10, wherein the movement is performed so as to be 1. 12. The image processing method according to claim 9, wherein the moving step moves in a direction in which a value of each element of a feature amount vector of the target binary image increases. 13. The feature amount space is a set of vector information indicating whether or not a peripheral pixel of the pixel exists in each pixel of the contour image of the target binary image. Item 10. The image processing method according to Item 9. 14. The object 2 changed in the changing step
The image processing method according to claim 9, further comprising a printing step of printing based on image data corresponding to the value image. 15. The object 2 changed in the changing step
Reading an original image formed based on the value image, extracting an outline of the image, obtaining a pattern vector of an image corresponding to the outline, and obtaining the reference pattern vector and the pattern vector. 10. A detection step of obtaining the correlation coefficient of the above in the calculation step, and detecting the access control information embedded in the document image according to the correlation coefficient. Image processing method. 16. An extraction step of reading a document image and extracting a contour part of the image, a step of obtaining a pattern vector of an image corresponding to the contour part, and a step of obtaining a pattern vector of a reference pattern and a pattern vector of the image. A correlation coefficient calculating step of calculating a correlation coefficient; and a detecting step of detecting control information embedded in the document image according to the correlation coefficient obtained in the correlation coefficient calculating step. An image processing method characterized by the following. 17. A computer-readable storage medium storing a control program for executing the image processing method according to claim 9. Description: