JP2015012444A - Apparatus for embedding information into document file - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for embedding information into a document file, capable of embedding high-capacity data of characters or images in an invisible state completely without deteriorating quality of a source document and extracting embedded information only by a widespread reader without using a dedicated extraction tool.SOLUTION: An apparatus comprises: additional information arrangement means 10 for arranging additional information of a character code form within an image region where an image is disposed beforehand within a document file; display priority change means 20 for arranging the additional information in a lower layer after changing a display priority of the additional information lower than that of the image arranged beforehand; and document format conversion means 50 for converting the document file of which the display priority has been changed by the display priority change means 20, into an embedded document file of a predetermined format so as to select and extract the additional information of the character code form within the image region when browsing the document file after embedment.

Description

  The present invention relates to a technique for embedding information in a document file such as PDF (Portable Document Format: registered trademark).

  In recent years, PDF document files have come to be used as official documents such as contracts, and security functions can be electronically stamped or encrypted with a document to control opening, printing, editing, etc. with a password. Can be added. However, once a password is obtained and can be opened, there may be a problem that an inexhaustible copy is created, so tracking with a digital watermark is also necessary. Although a technique for embedding a visible digital watermark in a PDF document has also been developed (see Patent Document 1), a technique for embedding an invisible digital watermark has not been developed, and an invisible digital watermark is embedded in individual images to be laid out. However, there was only means.

  As a method of adding invisible information to a PDF document, there is a method of arranging transparent text, but the text that can be arranged is limited to a character string recognized by OCR processing for raster format character data arranged in the PDF. There was a problem of being. In addition, image data and document data can be attached to a PDF document as an attached file, but since it is clearly indicated on the PDF reader, it cannot be said that it is embedded in an invisible state.

Japanese Patent No. 4698535

  On the other hand, invisible digital watermark technology for images and texts, there is a problem of modifying and degrading the quality of the original content, the amount of embedded information is limited, and it is difficult to embed large amounts of data such as image data. There was a problem that extraction could not be performed if the exclusive extraction software corresponding to was not available.

  Therefore, the present invention can embed a large amount of data such as characters and images in an invisible state without degrading the quality of the original document at all, and is a popular reader without using a dedicated extraction tool. It is an object of the present invention to provide an information embedding device for a document file that can extract information embedded by itself.

  In order to solve the above-described problem, according to the first aspect of the present invention, there is provided an apparatus for recording additional information in a character code format in an invisible state on a document file in which an image is arranged. In the image area where the image is arranged, additional information arrangement means for arranging the additional information in the character code format, and lowering the display priority of the additional information from the display priority of the previously arranged image Display priority changing means for changing to arrange in a layer, and changing the display priority so that additional information in the character code format can be selected and extracted in the image area when viewing the embedded document file And a document format conversion means for converting the document file whose display priority has been changed by the means into a predetermined format. To provide an implanted device.

  According to the first aspect of the present invention, the additional information in the character code format is arranged in the image area where the image is arranged in advance in the document file, and the display priority of the additional information is set in the image arranged in advance. Changed to lower the display priority and place it in the lower layer, and when viewing the embedded document file, the document file can be selected and extracted so that additional information in the character code format can be selected and extracted in the image area. Since it is converted into a format, it is possible to embed additional information in the character code format in an invisible state under the image without degrading the quality of the original document at all, and generally without using a dedicated extraction tool. A popular reader makes it possible to extract the embedded character code when attempting to duplicate an image.

  According to a second aspect of the present invention, there is provided an apparatus for recording additional information in a character code format in an invisible state with respect to a document file in which characters are arranged, wherein the characters are arranged in advance in the document file. The additional information arrangement means for arranging the additional information in the character code format in the background color of the document file in the character area, and lowering the display priority of the additional information from the display priority of the characters arranged in advance. Display priority changing means for changing to be arranged in a lower layer, and the display priority so that additional information in the character code format can be selected and extracted in the character area when the embedded document file is viewed A document format conversion means for converting a document file whose display priority has been changed by the degree change means into a predetermined format. To provide information embedding device to.

  According to the second aspect of the present invention, the additional information in the character code format is arranged in the background color of the document file in the character area where the characters are arranged in advance in the document file, and the display priority of the additional information is set. Is changed to lower the display priority of the pre-arranged characters and placed in the lower layer, so that additional information in the character code format can be selected and extracted in the character area when viewing the embedded document file As described above, since the document file is converted into a predetermined format, additional information in the character code format can be embedded in an invisible state under the character without any deterioration in the quality of the original document. An embedded character code can be extracted when attempting to duplicate characters by a widely used reader without using a dedicated extraction tool.

  According to a third aspect of the present invention, there is provided an apparatus for recording bitmap format additional information in an invisible state with respect to a document file in which an image is arranged. The bitmap format so that a predetermined range of the boundary of the bitmap is expanded by a predetermined width by the background color of the document file, and the expanded area protrudes outside the image area where the image is arranged in advance. Additional information arrangement means for arranging the additional information in the image area, and lowering the display priority of the additional information in the bitmap format from the display priority of the pre-arranged image so that the additional information is arranged in the lower layer. The display priority changing means to be changed and the additional information in the bitmap format are selected and extracted in the expanded area when browsing the embedded document file. Provided is an information embedding device for a document file, comprising: a document format converting unit that converts a document file whose display priority has been changed by the display priority changing unit into a predetermined format. To do.

  According to the third aspect of the present invention, a predetermined range of a bitmap boundary is expanded by a predetermined width with a background color of a document file with respect to additional information in a bitmap format, and is extended outside an image area in the document file. The additional information in the bitmap format is arranged in the image area so that the projected area protrudes, and the display priority of the additional information in the bitmap format is set lower than the display priority of the image arranged in advance. Changed to be placed in a layer, and converted the document file to a predetermined format so that additional information in the bitmap format can be selected and extracted within the expanded area when viewing the embedded document file Therefore, it is possible to embed additional information in bitmap format under the image in an invisible state without degrading the quality of the original document at all. The reader has become popular without a le, when trying to duplicate the image to be extracted bitmap image embedded.

  In the fourth aspect of the present invention, the additional information arrangement means further adds the additional information in the character code format to the document file in a background area where neither characters nor images in the document file are arranged. The document format conversion means selects and extracts the additional information in the character code format arranged by the additional information arrangement means in the background area when browsing the embedded document file. It is characterized in that it is converted into a predetermined format so that it becomes possible.

  According to the fourth aspect of the present invention, when the additional information is arranged, the additional information in the character code format is further displayed in the background color of the document file in the background area where neither the character nor the image in the document file is arranged. Since the additional information in the character code format is converted into a predetermined format so that it can be selected and extracted in the background area when browsing the embedded document file, On the other hand, additional information in the character code format can be embedded in the background invisible without degrading the quality at all, and it is embedded from the background by a popular reader without using a dedicated extraction tool. Enable extraction of character codes.

  According to the fifth aspect of the present invention, there is provided a document file in which images or characters can be recorded in a plurality of layers, and information recorded in a plurality of layers corresponding to a designated position can be selected. An image or a character for display is arranged in the layer, and an image or a character is recorded as invisible information in a layer below the layer in which the image or character for display is recorded. Provide a document file.

  According to the fifth aspect of the present invention, there is provided a document file in which images or characters can be recorded in a plurality of layers, and information recorded in a plurality of layers corresponding to a designated position can be selected. In this layer, images or characters for display are placed, and images or characters are recorded as invisible information in a layer below the layer where images or characters for display are recorded. By selecting, the information recorded in the lower layer is acquired, and it is possible to give the user an unexpected surprise and attention.

  According to the present invention, it is possible to embed a large amount of data such as characters and images in an invisible state without degrading the quality of the original document at all, and a reader that is generally spread without using a dedicated extraction tool. It becomes possible to extract the embedded information.

It is a hardware block diagram of the information embedding apparatus with respect to the document file which concerns on one Embodiment of this invention. It is a functional block diagram which shows the structure of the information embedding apparatus with respect to the document file which concerns on one Embodiment of this invention. It is a flowchart which shows the process outline | summary of the information embedding apparatus with respect to the document file which concerns on one Embodiment of this invention. It is a figure which shows an example of the document file before information embedding. It is a figure which shows the state of the document file after embedding character string arrangement | positioning. It is a figure which shows the state of the document file after embedding character string arrangement | positioning. It is a figure which shows the state of the document file after an embedded image arrangement | positioning. It is a figure which shows the state of the document file after the embedded character string arrangement | positioning in a background. It is a figure which shows the state of the document file after a display priority change. It is a flowchart which shows the extraction process of additional information at the time of using reading software. It is a flowchart which shows the extraction process of additional information at the time of using edit software. It is a display example of a document file before additional information is arranged. It is a display example of a document file in a state where additional information is arranged. It is a display example of a document file in a state where the upper and lower layers are changed. It is a display example of a document file in which information is embedded. It is a display example by the browsing software of the obtained embedded document file. It is a figure which shows the state from which the character string of the lower layer of the image was selected. It is a figure which shows duplication operation of the selected character string. It is a figure which shows the character string copied on the clipboard. It is a figure which shows the state from which the character string of the upper and lower layers was selected. It is a figure which shows duplication operation of the selected character string. It is a figure which shows the character string copied on the clipboard. It is a figure which shows the state from which the image of the lower layer hidden behind the upper image was selected. It is a figure which shows duplication operation of the selected image. It is a figure which shows the image copied on the clipboard.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings.
<1. Device configuration>
FIG. 1 is a hardware configuration diagram of an information embedding device for a document file according to an embodiment of the present invention. An information embedding apparatus for a document file according to the present embodiment can be realized by a general-purpose computer. As shown in FIG. 1, a CPU (Central Processing Unit) 1 and a RAM (Random Access Memory) which is a main memory of the computer. ) 2, a large-capacity storage device 3 such as a hard disk or flash memory for storing programs and data executed by the CPU 1, a key input I / F (interface) 4 such as a keyboard and a mouse, a data storage medium, etc. A data input / output I / F (interface) 5 for data communication with the external device and a display unit 6 which is a display device such as a liquid crystal display are connected to each other via a bus.

  FIG. 2 is a functional block diagram showing the configuration of the information embedding device for the document file according to this embodiment. In FIG. 2, 10 is an additional information arrangement unit, 20 is a display priority changing unit, 50 is a document format conversion unit, 60 is a document file storage unit, 61 is an additional information storage unit, and 70 is an embedded document file storage unit.

  The additional information arrangement unit 10 arranges the designated additional information in the additional information storage unit 61 at a designated position in the document file. The additional information is text or image information that is added to the originally recorded information and embedded in the document file. In this embodiment, characters are in the character code format and images are in the bitmap format. The display priority changing means 20 changes the display priority of the additional information so that it is placed on the lower layer by lowering it than other placement objects. The document format conversion means 50 converts the format of the document file in which the additional information is embedded, and creates an embedded document file of a predetermined format.

  The document file storage unit 60 is a storage unit that stores a document file that can be processed by a computer, and is realized by the storage device 3. The additional information storage unit 61 is a storage unit that stores additional information to be embedded in a document file, and is realized by the storage device 3. The embedded document file storage means 70 is a storage means for storing an embedded document file in which additional information is embedded in the original document file, and is realized by the storage device 3. Various types of embedded document files can be used. In this embodiment, the PDF format, which is a general-purpose format, is used. The additional information arrangement unit 10, the display priority change unit 20, and the document format conversion unit 50 are realized by the CPU 1 executing a program stored in the storage device 3.

  Each component shown in FIG. 2 is actually realized by mounting a program on hardware such as a computer and its peripheral devices as shown in FIG. That is, the computer executes the contents of each means according to the program. Note that in this specification, a computer means a device that has an arithmetic processing unit such as a CPU and is capable of data processing.

  The storage device 3 shown in FIG. 1 is mounted with a program for operating the CPU 1 and causing the computer to function as an information embedding device for document files. By executing this program, the CPU 1 realizes functions as the additional information arrangement unit 10, the display priority change unit 20, and the document format conversion unit 50. The storage device 3 not only functions as the document file storage unit 60, the additional information storage unit 61, and the embedded document file storage unit 70, but also stores various data necessary for processing of the document file as an information embedding device. .

<2. Processing action>
Next, the processing operation of the information embedding device for the document file shown in FIGS. 1 and 2 will be described. FIG. 3 is a flowchart showing an outline of processing performed by the information embedding device for a document file according to an embodiment of the present invention. First, the additional information arrangement unit 10 performs a process of arranging additional information (step S10). Specifically, first, the information embedding apparatus for the document file reads the specified document file from the document file storage unit 60 in accordance with a user instruction via the key input I / F 4.

  FIG. 4 shows an example of a document file before embedding additional information. FIG. 4 shows an arrangement state of objects when one page in the document file is displayed on the display unit 6. In the example of FIG. 4, character strings are arranged at the upper left, and images are arranged at the lower left and the right. The already-arranged character strings and images displayed in FIG. 4 are not information for embedding, but are displayed and printed to convey information to the user.

  The document file shown in FIG. 4 can be created in various known formats. For example, MS-Word (registered trademark), PowerPoint (registered trademark), Illustrator (registered trademark), InDesign (registered trademark), and the like can be used. Next, the user acquires a desired embedded character string from a text file recorded in advance in the additional information storage unit 61.

  First, the embedded character string is arranged so as to overlap the character string (step S11). The embedded character string is additional information in the character code format to be embedded. FIG. 5 shows the state of the document file after the embedded character string is arranged. As shown in FIG. 5, the embedded character string acquired from the additional information storage means 61 is arranged on the already arranged character string. Specifically, when an accurate arrangement position is designated via the key input I / F 4 and an arrangement instruction is given, the additional information arrangement unit 10 stores the embedded character string acquired from the additional information storage unit 61 in the document file. Place at the specified position.

  Next, the embedded character string is arranged so as to overlap the image (step S12). FIG. 6 shows the state of the document file after the embedded character string is arranged. As shown in FIG. 6, the embedded character string acquired from the additional information storage unit 61 is arranged on the already arranged image. Specifically, when an accurate arrangement position is designated via the key input I / F 4 and an arrangement instruction is given, the additional information arrangement unit 10 stores the embedded character string acquired from the additional information storage unit 61 in the document file. Place at the specified position.

  Subsequently, the embedded image is arranged so as to overlap the image (step S13). An embedded image is additional information in a bitmap format to be embedded, and is acquired from an image file recorded in the additional information storage unit 61 in the same manner as an embedded character string. The state of the document file after the embedded image is arranged is shown in FIG. As shown in FIG. 7, the embedded image acquired from the additional information storage unit 61 is arranged on the already arranged image. Specifically, when an accurate arrangement position is designated via the key input I / F 4 and an arrangement instruction is given, the additional information arrangement means 10 designates the embedded image acquired from the additional information storage means 61 in the document file. Place it at the specified position. At this time, the periphery of the image area is expanded by the same color as the background color of the document file by a predetermined width. The predetermined width can be set as appropriate, but it is preferably 50 to 100 pixels so that the selection operation can be easily performed as a portion protruding from the upper layer. Although all the surroundings may be expanded as shown in FIG. 7, it may be expanded at least in the direction of one side. That is, a predetermined range of the image area boundary may be expanded. However, this extension process is an additional process required when the extraction process described later is realized by reading software as shown in FIG. 10, and is unnecessary when realized by editing software as shown in FIG.

  Subsequently, an embedded character string is arranged in the background (step S14). FIG. 8 shows the state of the document file after the embedded character string is placed in the background. As shown in FIG. 8, the embedded character string obtained from the additional information storage unit 61 is arranged on a background where no image, character string, or the like is arranged. Specifically, when an accurate arrangement position is designated via the key input I / F 4 and an arrangement instruction is given, the additional information arrangement unit 10 stores the embedded character string acquired from the additional information storage unit 61 in the document file. Place at the specified position. The character string embedded in the background by the process of step S14 exists as a transparent character string.

  Here, the embedded character string arrangement over the character string (step S11), the embedded character string arrangement over the image (step S12), the embedded image arrangement over the image (step S13), and the embedded character string arrangement over the background (step S12) The processing is performed in the order of S14), but the processing in steps S11 to S14 may be performed in any order. Moreover, it is not necessary to perform all the processes of S11 to S14, and one or more processes may be performed.

  Next, the display priority of the arranged additional information is changed (step S20). Specifically, first, the user instructs display priority change in a state where all the additional information is arranged as shown in FIG. Then, the display priority changing unit 20 changes the display color only for the embedded character string to the background color, and sets the display priority of the arranged additional information based on the information such as the images and characters already arranged. Change it so that it is lowered and placed in the underlying layer. FIG. 9 shows the state of the document file after changing the display priority. In FIG. 9, a portion surrounded by a broken line indicates a portion hidden by another image or character area. As can be seen from comparison with FIG. 8, in FIG. 9, the display priority of the additional information is changed to a state where the additional information is moved to a lower layer and is hidden by another image or character area. In the upper left embedded character string in FIG. 9, the upper layer is also a character string, and in the upper right embedded character string in FIG. 9, there is no upper layer, so that it can be visible. Because the correction which changes the display color of to the background color is added, it becomes invisible.

  If the display priority has been changed, the document format conversion means 50 then converts the document format (step S30). Specifically, the document file can be selected in different image file formats (for example, widely used) so that the additional information can be selected and extracted in the existing image area, character area, and arrangement area when viewing the converted document file. Embedded document file is obtained. This is realized by using an algorithm similar to that of known PDF document format conversion software. Specifically, the document file after changing the display priority is recorded in various formats such as MS-Word (registered trademark), PowerPoint (registered trademark), Illustrator (registered trademark), InDesign (registered trademark). Each character string data in the character code format (Shift-JIS, etc.) and image data in the bitmap format (BMP format, etc.) are converted to the international standard PostScript (registered trademark) format. (Note that this conversion is not necessary because Illustrator (registered trademark) documents are originally written in PostScript format.) This conversion to PostScript format does not display character string data or images that are hidden in the underlying layer. The processing is uniformly performed on the data or on the character string data or image data designated with the transparent color (background color), and the display priority information is also inherited. In this conversion process, the character code constituting the character string data is often converted to an Adobe code other than Shift-JIS, and the bitmap constituting the image data is often compressed in JPEG format. In addition, for the convenience of inserting layout control data, character string data and image data are often divided as appropriate, and subsequently, character string data is converted into PostScript format character string data, image data, and graphic data. An international standard PDF document file is obtained by adding font data to be referred to, a color conversion table to which image data is referenced, and applying a lossless compression in the ZIP format to a single file. These series of processing can be realized by using editing software such as Adobe Acrobat (registered trademark). The embedded document file is stored in the embedded document file storage means 70.

<3. Extraction process>
Next, extraction of additional information from the obtained embedded document file will be described. Extraction of additional information from the embedded document file is performed by activating read software or editing software in a computer having a hardware configuration as shown in FIG. However, the computer is not limited to the one shown in FIG. 1, and a portable terminal such as a tablet computer can be used as long as the PDF file can be browsed and the arrangement information can be extracted from the PDF file.

  FIG. 10 is a flowchart showing an extraction process of additional information when reading software is used. First, the reading software is activated (step S51). As reading software, Adobe Reader (registered trademark) or the like can be used.

  Next, the character string in the lower layer of the character or image is selected on the screen (step S52). This is realized by designating via the key input I / F 4 according to the function of the reading software. At this time, if there are character strings in the upper layer, both upper and lower character strings are selected at the same time. If the upper layer is an image, only the lower character strings are selected. When the character string in the lower layer of the character or image is selected, it is transferred to a text editor such as “Notepad” by copy and paste (step S53). As a result, the extracted embedded character string is recorded in the text editor. When both upper and lower character strings are selected at the same time, both character strings are appropriately divided into phrase units (when the layout rule is changed when converted to PDF text format using Adobe Acrobat). (The character string is divided by punctuation marks / spaces, reciprocal change between half-width and full-width, etc.) and mixed (for example, the upper-layer character string 10 characters, the lower-layer character string 10 characters, the upper-layer character string) 10 characters ... are copied and pasted alternately).

  If the additional information is in the image format, after starting the reading software, an image of a layer below the image is selected on the screen (step S54). This is realized by designating via the key input I / F 4 according to the function of the reading software. When selecting an image, it is selected by designating the periphery of the superimposed images. As a result, the computer recognizes an embedded image having the designated position as an extension area. (The image is transferred to an image editor such as “paint tool” by copy and paste (step S55). Thereby, the extracted embedded image is recorded in the image editor.

  FIG. 11 is a flowchart showing additional information extraction processing when editing software is used. First, the editing software is activated (step S61). As the editing software, the above-mentioned Adobe Acrobat or the like can be used.

  Next, a text extraction function is executed (step S62). This is realized by designating via the key input I / F 4 according to the function of the editing software. Thereby, the embedded character string is extracted together with the already arranged character string.

  If there is additional information in the image format, the image extraction function is executed after the editing software is started (step S63). This is realized by designating via the key input I / F 4 according to the function of the editing software. Thereby, the embedded image is extracted together with the already arranged image.

  In the information embedding device of this embodiment, information is embedded invisible. Therefore, when the embedded document file is displayed, the additional information is not displayed, and the duplicator uses it without being aware that the additional information is embedded in the document file. However, when the process shown in FIGS. 10 and 11 is performed and characters and images are duplicated and pasted, embedded characters and images are extracted instead of the characters and images intended by the duplicator. . For this reason, it is possible to alert the person who easily copied the document file.

<4. Display example>
Next, specific display examples will be described with reference to FIGS. FIG. 12 is a display example of a document file before additional information is arranged. In FIG. 12, two objects of a character image, a character code, and an image are arranged. In addition, in order to clarify distinction from a character image that is an image, “character code” is described in FIG. 12, but this description corresponds to “character string” in FIGS. To do. The display example of FIG. 12 corresponds to FIG. However, the right image matches, but the upper left character image and the lower left character code are reversed. Although the character image represents characters, it is actually a bitmap image.

  FIG. 13 is a display example of a document file in which additional information is arranged. The display example of FIG. 13 corresponds to FIG. In the upper right background, a character string “Illegal copying strictly prohibited” is arranged. FIG. 14 is a display example of a document file in a state where the upper and lower layers are changed. The display example of FIG. 14 corresponds to FIG. In this process, the display color of the character string “Illegal copying strictly prohibited ...” in the upper right and the character string in the lower layer in the [Character code] field at the lower right is changed to the background color (white). FIG. 15 is a display example of a document file in which information is embedded. The appearance is the same as before embedding shown in FIG.

  The document file shown in FIG. 15 is converted into a document format, and an embedded document file is obtained. FIG. 16 is a display example of the obtained embedded document file by browsing software (Adobe Reader). The appearance is the same as the document file in which the information shown in FIG. 12 is not embedded.

  In the document file shown in FIG. 16, it is assumed that the duplicator tries to duplicate the character string displayed on the upper left. In this case, the duplicator selects a character string by dragging using the mouse. Then, as shown in FIG. 17, the shaded portion is selected. At first glance, it appears that the displayed character string is selected, just like the processing for a normal document file, but what is displayed is a character image, and is actually a character embedded in the lower layer. A column is selected. At this time, the character string embedded in the upper right background is also selected.

  Subsequently, as shown in FIG. 18, the duplicator performs an operation of copying the selected character string to the clipboard. Then, the selected character string is duplicated on the clipboard. FIG. 19 shows a character string copied to the clipboard. As can be seen from a comparison with FIG. 18, a character string different from the character string that seemed to be selected is duplicated on the clipboard. As shown in FIG. 19, the duplicated character string is preferably a sentence that warns that duplication is illegal.

  In the document file shown in FIG. 16, it is assumed that the duplicator tries to duplicate the character string displayed in the lower left. In this case, the user selects a character string by dragging using the mouse. Then, as shown in FIG. 20, the shaded portion is selected. At first glance, it appears that only the displayed character string is selected, as in the case of processing for a normal document file, but actually the character string embedded in both the upper and lower layers is selected.

  Subsequently, as shown in FIG. 21, the user performs an operation of copying the selected character string to the clipboard. Then, the selected character string is duplicated on the clipboard. FIG. 22 shows a character string copied to the clipboard. As can be seen from a comparison with FIG. 21, different character strings are duplicated on the clipboard, mixed with the character string that appeared to be selected. Therefore, the duplicated character string is very difficult to read as shown in FIG.

  In the document file shown in FIG. 16, it is assumed that the duplicator tries to duplicate the image displayed on the right side. In this case, the duplicator selects an image of the lower layer by clicking a little outside the image area using the mouse. Then, as shown in FIG. 23, the shaded portion is selected.

  Subsequently, as shown in FIG. 24, the duplicator performs an operation of copying the selected image to the clipboard. Then, the selected image is duplicated on the clipboard. FIG. 25 shows an image copied to the clipboard. As can be seen from a comparison with FIG. 24, an image different from the image that seemed to be selected is duplicated on the clipboard.

<5. Modified example>
The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments, and various modifications can be made. For example, in the above-described embodiment, characters and images are embedded only for display, but it is also possible to embed them so as to realize various functions by combination.

  For example, by embedding a character string in a lower layer of the image and causing the copied character string to be read by a known voice conversion device, the displayed image can be read out by voice.

  In addition, a musical score is displayed as an image, a character string specifying a musical score code is embedded in a lower layer of the image, and the music corresponding to the displayed musical score is automatically read by a known automatic performance device. It becomes possible to perform.

  In addition, it is possible to obtain information corresponding to the displayed product by displaying the product as an image, embedding a barcode image corresponding to the product in a lower layer of the image, and causing the barcode reader to read the image. It becomes possible.

  In the above embodiment, the information embedding device for the document file has the embedded character string arrangement over the character string (step S11 in FIG. 3), the embedded character string arrangement over the image (step S12 in FIG. 3), and the image overlaid on the image. It has all four configurations for embedded image layout (step S13 in FIG. 3) and embedded character string layout in the background (step S14 in FIG. 3), but it is realized as a device with one or more of these configurations. You may do it.

1 ... CPU (Central Processing Unit)
2 ... RAM (Random Access Memory)
3 ... Storage device 4 ... Key input I / F
5. Data input / output I / F
6 ... Display section 10 ... Additional information arrangement means 20 ... Display priority changing means 50 ... Document format conversion means 60 ... Document file storage means 61 ... Additional information storage means 70 ...・ Embedded document file storage means

Claims (5)

An apparatus for recording additional information in a character code format in an invisible state on a document file in which an image is arranged,
Additional information arrangement means for arranging additional information in the character code format in an image area in which an image is arranged in advance in the document file;
Display priority changing means for changing the display priority of the additional information to be lower than the display priority of the pre-arranged image and arranging it in the lower layer;
A document file whose display priority has been changed by the display priority changing unit is set to a predetermined format so that additional information in the character code format can be selected and extracted in the image area when the embedded document file is viewed. Document format conversion means for converting to
An information embedding device for a document file, comprising: An apparatus for recording additional information in a character code format in an invisible state on a document file in which characters are arranged,
Additional information arrangement means for arranging additional information in the character code format in a background color of the document file in a character area in which characters are arranged in advance in the document file;
Display priority changing means for changing the display priority of the additional information to be lower than the display priority of characters arranged in advance and arranging it in a lower layer;
A document file whose display priority has been changed by the display priority changing means is set in a predetermined format so that additional information in the character code format can be selected and extracted in the character area when the embedded document file is viewed. Document format conversion means for converting to
An information embedding device for a document file, comprising: A device that records additional information in a bitmap format in an invisible state on a document file in which an image is arranged,
A predetermined range of the bitmap boundary is expanded by a predetermined width with the background color of the document file with respect to the additional information in the bitmap format, and the extended range is outside the image area where the image is arranged in advance. Additional information arrangement means for arranging the additional information in the bitmap format in the image area so that the area protrudes,
Display priority changing means for changing the display priority of the additional information in the bitmap format to be lower than the display priority of the pre-arranged image and arranging it in the lower layer;
The document file whose display priority has been changed by the display priority changing unit is selected so that the additional information in the bitmap format can be selected and extracted in the expanded area when browsing the embedded document file. Document format conversion means for converting to a predetermined format;
An information embedding device for a document file, comprising: In any one of Claims 1-3,
The additional information arrangement means further includes:
In the background area where neither the character nor the image in the document file is arranged, the additional information in the character code format is arranged in the background color of the document file,
The document format conversion means includes:
When the embedded document file is viewed, the additional information in the character code format arranged by the additional information arrangement means is converted into a predetermined format so that it can be selected and extracted in the background area. The information embedding device for a document file according to any one of claims 1 to 3. It is a document file that can record images or characters on multiple layers, and can select information recorded on multiple layers corresponding to the specified position,
An image or text for display is arranged in the uppermost layer, and an image or text is recorded as invisible information in a layer below the layer in which the image or text for display is recorded. Embedded document file.

Images