JP2009021776A - Information adding device, information adding method, image forming apparatus, image addition program, and recording medium which stores the program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform image processing for increasing white area of an image to increase an amount of information which can be embedded when the amount of information which can be embedded in the image runs short when additional information is embedded in the image. <P>SOLUTION: The image is input and embedding information which is the additional information is simultaneously input (steps 101, 102). Whether or not the input information can be embedded in the input image is decided from a size of white background in the image (a step 103). When it is decided that embedding is impossible, the white background area is increased by forcibly performing editing of the image such as background removal and after that, processing for embedding the input information in the input image is performed (steps 104, 105). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an information addition apparatus, an information addition method, an image forming apparatus, an information addition program, and a recording medium storing the program, and in particular, an information addition apparatus that superimposes additional information based on visible information such as a dot pattern in an image. The present invention relates to an information addition method, an image forming apparatus, an information addition program, and a recording medium storing the program.

  In recent years, a method called electronic watermarking that superimposes various additional information on an image has been proposed in order to prevent copying of digital contents or to link digital data and print data. . As such methods, for example, a method of embedding information in a document image in an invisible manner using character spacing, a visible method of superimposing a dot pattern or the like on the original image, and the like are known. Both visible and invisible methods have a problem that the amount of information that can be embedded depends on the content. In the case of an embedding method using characters, the amount of information that can be embedded is reduced for an image with a small number of characters. In the case of an embedding method that superimposes a dot pattern, detection becomes difficult when most of the dot pattern is covered with content, and as a result, the amount of information that can be embedded is reduced. When embedding information is used for security purposes, if the necessary amount of information cannot be embedded, this can be a major security flaw.

  As a conventional technique related to a control method for forcibly embedding information when it becomes impossible to superimpose a necessary amount of information in the process of superimposing additional information on an image, for example, it is described in Patent Document 1 Technology is known. This prior art allows the user to easily grasp the relationship between the amount of embeddable information and the embedding strength when superimposing and embedding additional information in a document image. In order to embed desired information, the embedding process is performed by changing so as to deteriorate the tolerance / image quality determined before embedding.

  As another conventional technique for embedding information, for example, a technique described in Patent Document 2 is known. In this prior art, for every other word in a document traded in electronic form via a computer network, the combination of the length of the white space before the word and the length of the white space after the word is used as one code unit. By changing the ratio according to the bit value of the signature data, the certification data for protecting the copyright is embedded in the code.

Moreover, the technique described in patent document 3 etc. is known as another prior art. This prior art can easily superimpose information by a dot pattern representing a copyright holder on a printed matter without degrading the image quality, and can extract the information as necessary. Is.
JP 2004-104494 A JP-A-9-186603 JP 2003-28397A

  The prior art described in Patent Document 1 described above is a technique for forcibly embedding non-visible information, and has a problem that visible information cannot be forcibly embedded. The prior arts described in Patent Documents 2 and 3 relate to a technique for embedding visible information. However, when it becomes impossible to embed a necessary amount of information, information can be forcibly embedded. It has the problem that it cannot be done.

  The object of the present invention is to solve the above-mentioned problems of the prior art, and the amount of information (information) to be superimposed on an image by a dot pattern or the like, and the amount of information that can be superimposed determined by the white area of the image, Information adding apparatus, information adding method, and image forming apparatus capable of increasing the superimposable information amount by performing image processing for increasing the white area of the image when the superimposable information amount is insufficient Another object is to provide an information addition program and a recording medium storing the program.

  In order to achieve the above object, the first means of the present invention includes an image input means for inputting image information, an additional information input means for inputting additional information to be superimposed on the image information, and the input image information. On the other hand, when it is determined by the availability determination means that it is impossible to superimpose the input additional information that has been input, the image information has a predetermined Image editing means for creating an image on which the additional information can be superimposed by performing image processing, and information adding means for superimposing the additional information on the image created by the image editing means And

  Further, in the second means of the present invention, in the first means, the availability determination means is determined by the information amount of the input additional information and the size of the white area in the input image information. Whether or not the input additional information can be superimposed is determined based on the amount of information that can be superimposed on the image information.

  According to a third means of the present invention, in the first or second means, the image editing means changes the size of an object included in the image information, moves the position of the object, and the background of the image information. Alternatively, at least one process of background image removal is performed on the image information.

  The fourth means of the present invention is characterized in that in the first, second or third means, the user further has means for determining whether or not to superimpose the additional information on the image information. .

  According to a fifth aspect of the present invention, there is provided an information addition method in an information addition apparatus comprising an image input means and an additional information input means, wherein the image input means inputs an image on which the additional information is superimposed. And the additional information input means has a step of inputting the additional information, and determines whether or not the input additional information can be superimposed on the input image information. Image editing for creating an image on which the additional information can be superimposed by performing predetermined image processing on the image information when it is determined that the image cannot be superimposed by the availability determining step and the availability determining step. And an information adding step of superimposing the additional information on the image created by the image editing step.

  According to a sixth means of the present invention, in the fifth means, the availability determination step is determined by the information amount of the input additional information and the size of the white area in the input image information. Whether or not the input additional information can be superimposed is determined based on the amount of information that can be superimposed on the image information.

  According to a seventh means of the present invention, in the fifth or sixth means, the image editing step includes: changing the size of an object included in the image information; moving the position of the object; Alternatively, at least one process of background image removal is performed on the image information.

  Further, the eighth means of the present invention is characterized in that the fifth, sixth or seventh means further comprises a step of allowing a user to determine whether or not to superimpose the additional information on the image information. .

  According to a ninth aspect of the present invention, in the image forming apparatus, the information adding device according to one of the first to fourth means is provided.

  According to a tenth aspect of the present invention, there is provided an information addition program for superimposing the input additional information on the image information for superimposing the input additional information, and a process for inputting an image on which the additional information is superimposed. The process of inputting the additional information, the determination of whether or not the input additional information can be superimposed on the input image information, and the determination by the determination process. When it is determined that the image information cannot be performed, an image editing process for creating an image on which the additional information can be superimposed by performing predetermined image processing on the image information, and image information created by the image editing process Further, the information adding process for superimposing the additional information is executed by a CPU.

  An eleventh means of the present invention is characterized in that the information addition program according to the tenth means is stored in a recording medium.

  According to the present invention, when the visible additional information such as a dot pattern is superimposed on the image, even if the information capacity that can be superimposed on the image is insufficient with respect to the information amount to be superimposed, Information can be superimposed.

  Hereinafter, embodiments of an information adding apparatus, an information adding method, an image forming apparatus, an information adding program, and a recording medium storing the program according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a flowchart for explaining the overall processing operation of the information adding apparatus according to the first embodiment of the present invention. FIG. 2 is a flowchart for explaining the details of the embedding determination process in step 103 in the flow shown in FIG. FIG. 5 is a block diagram showing a functional configuration of the information adding apparatus according to the first embodiment of the present invention.

  First, the functional configuration of the first embodiment will be described with reference to FIG. In the first embodiment of the present invention described here, the present invention is applied to a FAX apparatus, and information is embedded by superimposing additional information on a FAX image. In the following description, superimposing additional information on an image is simply expressed as embedding information, and additional information to be superimposed is expressed as embedded information. The first embodiment of the present invention shown in FIG. 5 includes an image input unit 501 such as a scanner, an embedding determination unit 502, an embedded information input unit 503, an image editing unit 504, and an information embedding unit 506. Configured. Although the hardware configuration of the FAX apparatus is not shown, the hardware configuration includes a memory, a CPU, and the like. The above-described embedding possibility determination unit 502, embedded information input unit 503, image editing unit 504, and information embedding The unit 506 is configured by software, stored in a memory, and executed by a CPU, thereby realizing each function.

  Next, the overall processing operation of the information adding apparatus according to the first embodiment will be described with reference to the flow shown in FIG.

(1) First, an image to be transmitted by FAX is input from an image input unit 501 such as a scanner, and embedded information as additional information is input from an embedded information input unit 503. This embedded information may be any information such as FAX sender ID, FAX receiver ID, secret information that is not desired to be visually recognized from the FAX image output at the transmission destination (steps 101 and 102).

(2) When an image and embedding information are input, the embedding possibility determination unit 502 next determines whether or not the input information can be embedded in the input image. Details of this embedding determination process will be described later with reference to FIG. 2 (step 103).

(3) If it is determined in step 103 that the embeddability determination unit 502 determines that embedment is impossible, the image editing unit 504 forcibly edits the image such as background removal or background image removal to increase the white background area. The information embedding unit 506 then embeds the input additional information in the image created by the image editing unit (steps 104 and 105). ).

(4) If it is determined in step 103 that the embedding possibility determination unit 502 determines that embedding is possible, the information embedding unit 506 displays the input information in the input image without editing the image. An embedding process is performed (step 105).

  In the processing of step 104 described above, the image editing unit 504 edits the image such as background removal to increase the white background area. As this image editing, the position of the image is moved to increase the white background area. A method can also be used. In this method, for example, by moving the figure or the like and collecting the white background in one place (or a plurality of places), a larger amount of white background (for example, 1 cm square) necessary for data embedding is secured. . As a result, when there is a white frame of 5 mm square, data can be embedded even when data cannot be embedded therein. That is, by moving a certain content to the left and aligning the left white background frame with the right white background frame, a new 1 cm square white background can be created, and the writing capacity can be increased.

  Next, the details of the embedding determination process in step 103 in the flow shown in FIG. 1 will be described with reference to the flow shown in FIG.

(1) When this process is started, the embeddability determination unit 502 first calculates the embedded information amount A from the information amount of the input embedded information itself and the method of embedding the embedded information, and also receives the input. An information amount B, which is the amount of information that can be embedded, is calculated from the white background area of the image (steps 201 and 202).

  In the case where error correction coding processing is performed on embedded information, the amount of embedded information is calculated from the information amount disclosed in Japanese Patent Application Laid-Open No. Sho, a method of embedding embedded information. Become.

(2) Then, the embeddability determination unit 502 compares the information amount A and the information amount B calculated in steps 201 and 202 to determine whether the information amount B is larger than the information amount A ( Step 203).

(3) If it is determined in step 203 that the information amount B is larger than the information amount A, that is, if all of the information to be embedded can be embedded in the image, the flow of FIG. When the process proceeds to the information embedding process 105 in step 105 and the amount of information A is larger than the amount of information B, that is, when there is not enough embeddable information capacity of the image and all of the information to be embedded cannot be embedded The process proceeds to the image editing process 104 in step 104 of the flow shown in FIG.

  In the process of determining whether or not to embed as described with reference to the flow of FIG. 2, the amount of information that can be embedded is estimated from the area of the white background of the input image, but the embedding unit 506 once embeds the information in the image. It may be determined whether or not embedding is possible, such as being possible if embedding is possible, and not being possible if embedding is not possible.

  In the first embodiment of the present invention described above, the background removal is performed as the image editing when it is determined that embedding is impossible. However, information is embedded in the input image also by the background removal. When the capacity that can be used is insufficient, it is possible to embed additional information in the input image by using an image editing method described according to a second embodiment of the present invention described later.

  In the first embodiment of the present invention described above, the present invention is applied to a FAX apparatus and information as a digital watermark is embedded in an image to be transmitted. However, the present invention is not limited to information processing represented by a PC or the like. In application to an apparatus, when information is embedded in a PPT file or the like, the embeddable information capacity is increased by removing the PPT background or pattern using pattern matching or the like. You can also

  FIG. 4 is a flowchart for explaining the overall processing operation of the information adding apparatus according to the second embodiment of the present invention, FIG. 3 is a flowchart for explaining the image editing processing operation in step 407 in the flow shown in FIG. These are block diagrams which show the function structure of the information addition apparatus by the 2nd Embodiment of this invention. In the second embodiment of the present invention described here, the present invention is applied to an information processing apparatus such as a PC, and additional information is embedded in an ordinary document (including a character area, a picture area, a table area, etc.). It is an example.

  First, the functional configuration of the second embodiment will be described with reference to FIG. The second embodiment of the present invention shown in FIG. 6 includes an image input unit 601, such as a scanner, an embedding possibility determination unit 602, an embedding information input unit 603, an image editing unit 604, a forced embedding determination unit 605, And an information embedding unit 606. The hardware configuration of the information processing apparatus in which the information adding apparatus according to the second embodiment of the present invention is constructed is not shown, but includes a memory, a CPU, etc. The 602, the embedded information input unit 603, the image editing unit 604, the forced embedding determination unit 605, and the information embedding unit 606 are configured by software, stored in the memory, and executed by the CPU. Functions are realized.

  Next, the overall processing operation of the information adding apparatus according to the second embodiment will be described with reference to the flow shown in FIG.

(1) First, a document image is input from an image input unit 601 such as a scanner or a network, and embedded information as additional information is input from an embedded information input unit 603. When the image and the additional information are input, the embeddability determination unit 602 determines whether the input information can be embedded in the input image. This embedding possibility determination may be the same as in the case of the first embodiment of the present invention described with reference to FIG. 2 (steps 401 to 403).

(2) If it is determined in step 403 that the embeddability determination unit 602 determines that embedment is possible, the information embedding unit 606 embeds the input information in the input image without editing the image. (Step 406).

(3) If it is determined in step 403 that the embeddability determination unit 602 determines that embedding is not possible, the forced embedding determination unit 605 performs a process of forcibly embedding information by editing an image, or cancels information embedding. Let the user select It should be noted that it is possible to set forcibly embedding from the beginning by setting the driver or the like without causing the user to select (step 404).

(4) When the user cancels the information embedding by selecting the forced embedding in the process of step 404, the forced embedding determination unit 605 stops the information embedding processing operation (step 405).

(5) When the user selects execution of information embedding in the forced embedding selection in step 404, the image editing unit 604 edits the input image and embeds additional information in the image. The information embedding unit 606 embeds the input information (steps 407 and 406).

  Next, the image editing processing operation at step 407 in the flow shown in FIG. 4 will be described with reference to the flow shown in FIG. The image editing process described below can also be performed by the image editing process in the first embodiment of the present invention described above.

(1) In step 403 described with reference to FIG. 4, if the embedding possibility determination unit 602 determines that embedding is not possible, and in step 404 the forced information embedding execution is selected by the user, the image editing unit 604 602 uses the information amount A, which is the information amount of the information to be embedded, calculated by executing the processing described with reference to FIG. 2 and the information amount B, which is the information amount that can be embedded in the input image, to create a margin. In order to increase the amount of information that can be enlarged and embedded, editing is performed to reduce the image. This reduction is performed so that the information amount B that can be embedded is equal to the information amount A that is the information amount of the information to be embedded. That is, the image is reduced until a capacity corresponding to the amount of information to be embedded can be secured in the image (step 302).

(2) Immediately after the processing in step 302, information may be embedded in the image. However, since it is difficult to make the text too small and difficult to read, it is difficult to read the characters in the text area of the reduced image. When the size S is calculated, it is determined whether or not it is larger than a predetermined arbitrary size K, and the character size S in the character area of the reduced image is larger than the predetermined arbitrary size K If the characters are not too small, the process proceeds to the process of step 305 in which the additional information is embedded in the image (step 303).

(3) If it is determined in step 303 that the character size S of the character region of the reduced image has become smaller than the predetermined arbitrary size K, it is determined that the character has become too small. After securing the capacity for the amount of embedded information by reducing the character size until the character size reaches K, and further reducing the size of the other regions and moving (packing) them to fill the gaps between the regions. Then, the process proceeds to step 305 in which the additional information is embedded in the image (step 304).

  As described above, an example of the processing by the image editing unit 604 has been described. However, as image editing for reducing the space between lines or increasing the white area, editing such as reducing the space between the lines of the document instead of reducing the entire image, or reducing the character font. You can also use the method. Also in this case, when necessary information cannot be embedded, processing similar to the processing in step 304 can be performed.

  Each process in each embodiment of the present invention described above is configured by a program and can be executed by a CPU included in each apparatus to which the present invention is applied. These programs include FD, CDROM, DVD, and the like. It can be provided by being stored in a recording medium, and can be provided as digital information via a network.

  As can be seen from the above description, the embodiment of the present invention embeds additional information in the white background portion of the input image. Here, the relationship between the amount of information that can be embedded and the white background area will be described. Normally, when the background of an image is not white and there is content there, if information is forcibly embedded, the embedded pattern is crushed by the content, and the embedded pattern cannot be extracted. That is, the area of the image in which information can be embedded is limited to the white background area of the image, and only the embedded pattern embedded in the white background area can be extracted. For this reason, the larger the white area of the image, the greater the amount of information that can be embedded.

  FIG. 7 is a diagram for briefly explaining a method for calculating the embeddable information capacity from the white background area of the input image. Next, this will be described. Note that a method for obtaining a white background area in an image can be realized by using a method known as an image area separation technique, and thus description thereof is omitted.

  Before describing FIG. 7, a method of calculating the amount of information of input additional information, that is, embedded information will be described. The calculation of the amount of embedded information depends on how the embedded information is specified. For example, when specifying an embedding method, the embedding method is associated with the amount of information that can be embedded by the embedding method. This can be done by preparing a prepared table. Also, for example, when it is specified that “XX information (text data such as user name, date, etc.) is to be embedded, the amount of information to be embedded is calculated by converting“ XX information ”into a bit string. can do.

Next, a method for calculating the amount of information that can be embedded in an image will be described. First, if it depends only on the area, a table is prepared in which the amount of information I that can be embedded and the area S necessary for embedding are prepared,
Embeddable information amount = (margin area / S) * I
Can be calculated as

In addition, when depending on the embedding rectangle S, a table is prepared in which information amount I that can be embedded and information on the rectangle S necessary for embedding are prepared, and how many rectangles S can be taken from the blank area. Calculate (K). And
When repeatedly embedding the same information → Amount of embeddable information: I
When embedding different information for each rectangle → Amount of information that can be embedded: K * I
When S cannot be taken from the blank area → Amount of embeddable information: 0
Can be calculated as

Also, if the amount of information is 0 if any part of the barcode is missing,
When S is not included in the blank area → Amount of embeddable information: 0
When S is included in the margin area → Amount of information that can be embedded: I
Can be calculated as

  Returning to the reference of FIG. 7, it is assumed that an embedding pattern A having an embedding information amount E as shown in FIG. 7A is input as information to be embedded. Further, as shown in FIG. 7B, it is assumed that a plurality of white background areas B1 to B3 (actually B1, B2,... Bn) exist in the input image. Then, a white background area having the maximum size among the white background areas B1 to B3 is obtained, and is set as Bmax. As shown in FIG. 7C, if the embedding pattern A is within Bmax, the information capacity that can be embedded in the image is E, and the final information capacity that can be embedded even when the same pattern is repeatedly embedded. Is also E. Further, as shown in FIG. 7D, if the embedding pattern A does not fit in B2, the information capacity that can be embedded in this white background area is zero.

  When the amount of information to be embedded is increased by repeatedly embedding the embedded pattern A by changing the pattern, the next largest white background area Bn is obtained, and the number of times C that the embedded pattern A fits into Bn is counted. Thus, the final embeddable information capacity can be obtained as E × C.

  However, when an error correction code or the like is used, the amount of information that can be embedded in an image may not be obtained simply by the method based on the area as described above. After embedding, the information can be detected, and a method of determining whether the embeddable information capacity satisfies the standard can be used depending on whether the information can be detected.

  The information adding apparatus according to each embodiment of the present invention described above can be configured in a FAX apparatus, a copying apparatus, a printing apparatus, or an image forming apparatus such as an MFP that combines these apparatuses. Each embodiment of the present invention can be configured in an information processing apparatus such as a PC. Furthermore, the embedded information that is additional information can be created by an information processing apparatus such as a FAX apparatus, a copying apparatus, a printing apparatus, an MFP that combines these, or a PC.

It is a flowchart explaining the whole processing operation of the information addition apparatus by the 1st Embodiment of this invention. 3 is a flowchart for explaining details of a process for determining whether or not to embed in step 103 in the flow shown in FIG. 1. 5 is a flowchart for explaining an image editing processing operation in step 407 in the flow shown in FIG. 4. It is a flowchart explaining the whole processing operation of the information addition apparatus by the 2nd Embodiment of this invention. It is a block diagram which shows the function structure of the information addition apparatus by the 1st Embodiment of this invention. It is a block diagram which shows the function structure of the information addition apparatus by the 2nd Embodiment of this invention. It is a figure explaining simply about the method of calculating the information capacity which can be embedded from the white background area of an input image.

Explanation of symbols

501 and 601 Image input unit 502 and 602 Embeddability determination unit 503 and 603 Embedded information input unit 504 and 604 Image editing unit 605 Forced embedding determination unit 506 and 606 Information embedding unit

Claims (11)

Image input means for inputting image information;
Additional information input means for inputting additional information to be superimposed on the image information;
Availability determination means for determining whether or not the input additional information can be superimposed on the input image information;
An image editing means for creating an image capable of superimposing the additional information by performing predetermined image processing on the image information when it is determined by the availability determining means that the image cannot be superimposed;
An information addition apparatus comprising: an information addition unit that superimposes the additional information on the image created by the image editing unit.   The availability determination unit is configured to input the additional information based on the information amount of the input additional information and the information amount that can be superimposed on the image information determined by the size of the white area in the input image information. The information adding apparatus according to claim 1, wherein it is determined whether or not the information can be superimposed.   The image editing means performs at least one of processing on the image information to change the size of the object included in the image information, move the position of the object, and remove the background or background image of the image information. The information adding device according to claim 1 or 2, characterized in that   4. The information adding apparatus according to claim 1, further comprising means for allowing a user to determine whether or not to superimpose the additional information on the image information. An information addition method in an information addition apparatus comprising an image input means and additional information input means,
The image input means includes a step of inputting an image on which the additional information is superimposed;
The additional information input means includes a step of inputting the additional information;
A permission determination step of determining whether or not the input additional information can be superimposed on the input image information;
An image editing step for creating an image on which the additional information can be superimposed by performing predetermined image processing on the image information when it is determined that the image cannot be superimposed by the permission determination step;
An information addition method comprising: an information addition step of superimposing the additional information on the image created by the image editing step.   In the availability determination step, the additional information input based on the information amount of the input additional information and the information amount that can be superimposed on the image information determined by the size of the white area in the input image information. 6. The information adding method according to claim 5, wherein it is determined whether or not the information can be superimposed.   The image editing step performs at least one of processing on the image information to change the size of the object included in the image information, move the position of the object, and remove the background or background image of the image information. 7. The information adding method according to claim 5, wherein the information is added.   8. The information adding method according to claim 5, further comprising a step of causing a user to determine whether or not to superimpose the additional information on the image information.   An image forming apparatus comprising the information adding device according to claim 1. An information addition program for superimposing input additional information on image information for superimposing input additional information,
A process of inputting an image on which the additional information is superimposed;
A process of inputting the additional information;
A determination process for determining whether or not the input additional information can be superimposed on the input image information;
An image editing process for creating an image on which the additional information can be superimposed by performing predetermined image processing on the image information when it is determined that the image cannot be superimposed by the permission determination process;
An information addition process for superimposing the additional information on the image information created by the image editing process;
An information addition program which causes a CPU to execute   A recording medium storing the information addition program according to claim 10.

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