JP5557756B2 - Digital watermark embedding device, digital watermark embedding program, digital watermark detection device, and digital watermark detection program - Google Patents

Description

  The present invention relates to a digital watermark embedding device, a digital watermark embedding program, a digital watermark detection device, and a digital watermark detection program.

  Conventionally, a digital watermark (hereinafter referred to as “a digital watermark”) that can detect embedded information even from a video captured by a video camera (hereinafter referred to as “re-captured”) or a video compressed by an encoding method such as MPEG-2. A technique of “digital watermark having reshooting resistance” has been proposed (for example, see Patent Document 1).

International Publication No. 05/079072

  However, in the conventional digital watermark, there is no mention of a technology that detects illegal copies of content at high speed and efficiently eliminates it, and a technology that effectively identifies a program or broadcast material in a broadcasting station. There was a problem that the watermark could not be used practically.

  The present invention has been made in view of the above points, and can effectively detect illegal copies of contents at high speed by using digital watermarks and efficiently identify programs or broadcast materials at a broadcasting station. An object is to provide a digital watermark embedding device, a digital watermark embedding program, a digital watermark detection device, and a digital watermark detection program.

  In order to solve the above problem, an electronic watermark embedding device according to claim 1 is an electronic watermark embedding device that generates an electronic watermark embedded moving image content by embedding an electronic watermark in the moving image content, The digital watermark embedding unit and the region dividing unit are included, and the digital watermark embedding unit includes a basic identification information embedding unit.

  According to such a configuration, the digital watermark embedding device specifies the pixel block unit corresponding to one bit of the digital watermark as the embedding unit in the frame image constituting the moving image content by the embedding unit specifying unit. Further, the digital watermark embedding means adds a digital watermark including one or more basic identification information, which is configured in a predetermined number of pixel block units and is information for distinguishing the moving image content from other moving image content, to the frame image. Embed. Further, the frame image is divided into a plurality of embedding areas by the area dividing means.

  Then, the basic identification information embedding unit embeds basic identification information at least once for each of a plurality of embedding areas. For this reason, the digital watermark embedding device can double the number of basic identification information that can be embedded in one frame image by the number of embedding areas, so that a more severe deterioration occurs in a part of the frame image. Even so, it is possible to generate a digital watermark-embedded moving image content capable of detecting a digital watermark from basic identification information of other parts.

  According to another aspect of the present invention, there is provided a digital watermark embedding device according to claim 2, wherein the digital watermark embedding device generates a digital watermark embedded video content by embedding the digital watermark in the video content. Means, an electronic watermark embedding means, and an embedded data generating means, and the electronic watermark embedding means is configured to repeatedly embed embedded data in a frame image a predetermined number of times.

  According to such a configuration, the digital watermark embedding device specifies the pixel block unit corresponding to one bit of the digital watermark as the embedding unit in the frame image constituting the moving image content by the embedding unit specifying unit. Further, the digital watermark embedding means adds a digital watermark including one or more basic identification information, which is configured in a predetermined number of pixel block units and is information for distinguishing the moving image content from other moving image content, to the frame image. Embed. Further, the embedded data generating means generates digital watermark embedded data including one or more of the same basic identification information. Therefore, since the electronic watermark embedding apparatus can embed one or more pieces of basic identification information in a frame image at a time, the number of digital watermark embedding processes can be reduced and the overall processing speed can be increased.

  According to a third aspect of the present invention, there is provided a digital watermark embedding device according to the first aspect, comprising the related information embedding unit in the digital watermark embedding device according to the first aspect.

  According to such a configuration, the digital watermark embedding device embeds the related information, which is information related to the moving image content, at least once for each of the plurality of embedding areas by the related information embedding unit. For this reason, the digital watermark embedding apparatus can double the number of related information that can be embedded in one frame image by the number of embedding areas, so that a more severe deterioration occurs in a part of the frame image. Even in such a case, it is possible to generate a digital watermark-embedded moving image content capable of detecting a digital watermark from related information of other parts.

  The digital watermark embedding device according to claim 4 is the digital watermark embedding device according to claim 2, wherein the embedded data generation means is information related to moving image content while including one or more of the same basic identification information. The digital watermark embedded data including one or more related information is generated.

  According to such a configuration, the digital watermark embedding apparatus can embed one or more basic identification information and one or more related information in a frame image at a time, thereby reducing the number of digital watermark embedding processes, The overall processing speed can be increased.

  Further, in the digital watermark embedding device according to claim 3 or claim 4, the basic identification information may be a name or name of a copyright holder of the moving image content or an identifier of the moving image content.

  Furthermore, in the digital watermark embedding device according to any one of claims 3 to 5, the related information is metadata other than the metadata describing the name of the moving image content or the name of the copyright holder of the moving image content. The digital watermark embedding device according to any one of claims 3, 4 and 6, wherein the metadata may be metadata describing rights information or rights information other than the name of the copyright holder of the moving image content. In the configuration, the related information may be information indicating a shooting date or a shooting location of the moving image content.

  In order to solve the above-described problem, an electronic watermark embedding program according to claim 9, an embedding unit specifying unit, an embedding electronic device, The digital watermark embedding unit includes a basic identification information embedding unit that functions as a watermark embedding unit and an area dividing unit.

  According to such a configuration, the digital watermark embedding program specifies the pixel block unit corresponding to one bit of the digital watermark as the embedding unit in the frame image constituting the moving image content by the embedding unit specifying unit. Further, the digital watermark embedding means adds a digital watermark including one or more basic identification information, which is configured in a predetermined number of pixel block units and is information for distinguishing the moving image content from other moving image content, to the frame image. Embed. Further, the frame image is divided into a plurality of embedding areas by the area dividing means.

  Then, the basic identification information embedding unit embeds basic identification information at least once for each of a plurality of embedding areas. Therefore, the digital watermark embedding program can double the number of basic identification information that can be embedded in one frame image by the number of embedding areas, so that a more severe deterioration occurs in a part of the frame image Even so, it is possible to generate a digital watermark-embedded moving image content capable of detecting a digital watermark from basic identification information of other parts.

  In order to solve the above-described problem, a digital watermark embedding program according to claim 10, in order to generate a digital watermark-embedded moving image content by embedding the digital watermark in the moving image content, The digital watermark embedding means is configured to repeatedly embed the embedded data in the frame image a predetermined number of times.

  According to such a configuration, the digital watermark embedding program specifies the pixel block unit corresponding to one bit of the digital watermark as the embedding unit in the frame image constituting the moving image content by the embedding unit specifying unit. Further, the digital watermark embedding means adds a digital watermark including one or more basic identification information, which is configured in a predetermined number of pixel block units and is information for distinguishing the moving image content from other moving image content, to the frame image. Embed. Further, the embedded data generating means generates digital watermark embedded data including one or more of the same basic identification information. Therefore, the digital watermark embedding program can embed one or more pieces of basic identification information in a frame image at a time, so that the number of digital watermark embedding processes can be reduced and the overall processing speed can be increased.

In order to solve the above-described problem, the digital watermark detection apparatus according to claim 11 distinguishes the moving image content from other moving image contents in each of a plurality of embedded regions in the frame image constituting the moving image content. the basic identification information from the electronic watermark embedding moving image content targeted electronic watermark containing related information is information related to the moving image content of one or more are embedded with comprises one or more is information, according claim 1 An electronic watermark detection apparatus for detecting an electronic watermark generated by the electronic watermark embedding apparatus according to any one of items 10, wherein the electronic watermark detection means includes a basic identification information detection unit and a related information detection unit It was set as the structure provided with.
In the digital watermark detection apparatus, the basic identification information detection unit and the related information detection unit determine embedded bits for each of a plurality of embedded regions in a frame image constituting the moving image content, and the plurality of determination results are complementary. Thus, a final embedded bit corresponding to the basic identification information and the related information is determined.

According to such a configuration, the digital watermark detection apparatus detects the basic identification information from the plurality of embedded regions by the basic identification information detection unit, and detects the related information from the plurality of embedded regions by the related information detection unit. In addition, the detection process can be performed in two stages.
Furthermore, the digital watermark detection apparatus can detect the contents (basic identification information and related information) of the digital watermark embedded in the frame image by integrating the determination results for each of the plurality of embedded regions.

  A digital watermark detection apparatus according to a twelfth aspect is the digital watermark detection apparatus according to the eleventh aspect, further comprising a search keyword input unit and a moving image content collection unit, and a basic identification information detection unit and a related information detection unit. However, the basic identification information and the related information are detected from a plurality of embedded regions in the frame image constituting the collected moving image content.

  According to such a configuration, the digital watermark detection apparatus inputs a search keyword for searching for moving image content existing on a preset website on the communication network by the keyword input unit. Also, the moving image content collecting means searches for moving image content existing on the website according to the search keyword, and collects the moving image content. For this reason, the digital watermark detection apparatus detects a portion of the frame image in order to detect whether basic identification information or related information is embedded in a plurality of embedded regions of the frame image constituting the moving image content that matches the keyword. Even when degradation occurs in the digital watermark, the digital watermark can be detected from the basic identification information or the related information of other parts.

  A digital watermark detection apparatus according to a thirteenth aspect is the digital watermark detection apparatus according to the eleventh aspect, wherein a moving image content receiving unit, a moving image content decoding unit, a first database storage unit, and a second database storage unit are provided. And the basic identification information detection unit and the related information detection unit detect the basic identification information and the related information from a plurality of embedded regions in the frame image constituting the decoded moving image content, and the first database The text information corresponding to the basic identification information and the related information is extracted from the storage means and the second database storage means, respectively.

  According to such a configuration, the digital watermark detection apparatus receives the moving image content via the transmission path by the moving image content receiving unit. The received moving image content is decoded into a baseband signal by the moving image content decoding means. In the electronic watermark detection apparatus, the first database storage unit stores the name of the moving image content or the description of the moving image content as text information in association with the basic identification information of the moving image content. At the same time, the second database storage means stores the map information of the place where the moving image content is photographed as text information in association with the related information of the moving image content. Therefore, when the digital watermark detection apparatus receives moving image content via a transmission path, in addition to detecting basic identification information and related information, information related thereto is also extracted. For example, even when moving image content whose transmission source or name is unknown is received, the transmission source or name can be grasped.

In order to solve the above-described problem, the digital watermark detection program according to claim 12 includes basic identification information, which is information for distinguishing the moving image content from other moving image content in a frame image constituting the moving image content. from watermarked moving image content watermarking include relevant information one or more is information related to the moving image content embedded with comprises one or more, any one of claims 1 to 10 In order to detect the digital watermark generated by the digital watermark embedding device described in 1), the computer is configured to function as a digital watermark detection unit including a basic identification information detection unit and a related information detection unit.

  According to such a configuration, the electronic watermark detection program detects the basic identification information from the frame image by the basic identification information detection unit, and detects the related information from the frame image by the related information detection unit. The detection process can be performed in two stages so as to detect.

  According to the first to tenth aspects of the present invention, even when a part of the frame image is deteriorated by repeatedly embedding the basic identification information in the frame image, the electronic watermark detection apparatus performs basic of other parts. Since the digital watermark can be detected from the identification information, an illegal copy of the content can be detected at high speed and efficiently eliminated, and the program or broadcast material can be effectively identified at the broadcast station.

According to the invention of claims 11 to claims 1 to 4, that the basic identification information is repeatedly embedded in the frame image, even when a part of the frame image is degraded, the basic identity of the other portion Since a digital watermark can be detected from information, illegal copies of content can be detected at high speed and efficiently eliminated, and programs or broadcast materials can be effectively identified at a broadcast station.

1 is a block diagram showing an overall configuration of a digital watermark embedding device according to a first embodiment of the present invention. It is the schematic for demonstrating the embedding area | region of an image frame. It is the schematic for demonstrating the data arrangement | sequence of the digital watermark in the embedding area | region of an image frame. It is a flowchart for demonstrating operation | movement of the digital watermark embedding apparatus which concerns on 1st Embodiment of this invention. It is a block diagram which shows the whole structure of the digital watermark embedding apparatus which concerns on 2nd Embodiment of this invention, or its modification. 1 is a block diagram showing an overall configuration of a digital watermark detection apparatus according to a first embodiment of the present invention. It is a flowchart for demonstrating operation | movement of the digital watermark detection apparatus which concerns on 1st Embodiment of this invention. It is a block diagram which shows the whole structure of the digital watermark detection apparatus which concerns on 2nd Embodiment of this invention. It is a flowchart for demonstrating operation | movement of the digital watermark detection apparatus which concerns on 2nd Embodiment of this invention.

  An electronic watermark embedding device, an electronic watermark embedding program, an electronic watermark detection device, and an electronic watermark detection program according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the same configuration is given the same name and symbol, and detailed description is omitted.

<Digital watermark embedding device>
[First Embodiment]
Hereinafter, the digital watermark embedding device 1 according to the first embodiment will be described in detail with reference to FIGS. The digital watermark embedding device 1 generates a digital watermark embedded moving image content by embedding the digital watermark in the moving image content. Specifically, as shown in FIG. 1, the digital watermark embedding apparatus 1 includes an embedding unit specifying means 9, an area dividing means 10, and a digital watermark embedding means 20. Hereinafter, each component provided in the digital watermark embedding apparatus 1 will be described.

  The embedding unit specifying means 9 is for specifying a pixel block unit corresponding to 1 bit of a digital watermark as an embedding unit in one frame image. This pixel block is composed of at least one pixel. For example, when a pixel block is composed of a plurality of pixels, such as a plurality (100 pixels) composed of 10 × 10 pixels, the pixel The same digital watermark is embedded in the block. The number of pixels of the pixel block specified by the embedding unit specifying means 9 is not particularly limited, and is not limited to the one or 100 pixels described above.

  The area dividing means 10 divides the frame image of the moving image content into a plurality of embedded areas, and a digital watermark is embedded in the embedded area. The area dividing means 10 divides the frame so that the divided embedding area can be embedded a plurality of times repeatedly by the electronic watermark embedding means 20 described later. As shown in FIG. 2, the area dividing unit 10 in this embodiment divides each frame image constituting the moving image content into, for example, eight areas (1) to (8). Then, the region dividing unit 10 generates information on the division position of the frame image (for example, the coordinates of the pixel located at the boundary of each embedded region). In the embedding area of the present embodiment, the same data is embedded in the eight embedding areas (1) to (8) obtained by dividing one frame.

  As shown in FIG. 1, moving image content is input to the region dividing means 10 from a moving image content storage device or the like (not shown). Then, the region dividing unit 10 divides the frame image into a plurality of embedding regions by the above-described method, and outputs the frame image and information on the division position of the frame image to the digital watermark embedding unit 20 as shown in FIG. To do.

  The electronic watermark embedding unit 20 embeds an electronic watermark including basic identification information and related information, with one pixel block as 1-bit data, in a frame image constituting moving image content. Specifically, as shown in FIG. 1, the digital watermark embedding unit 20 includes a basic identification information embedding unit 201 for embedding basic identification information in a frame image, and a related information embedding unit 202 for embedding related information in a frame image. The basic identification information and the related information are embedded separately in the frame image.

  Here, the basic identification information means information necessary for distinguishing moving image content from other moving image content. The basic identification information is configured in units of a predetermined number of pixel blocks. The specific contents of the basic identification information differ depending on the use of the digital watermark. For example, when the digital watermark is used for detecting an illegal copy of the content, the copyright of the moving image content such as the name or name of the copyright holder is used. Information for identifying the right holder can be used as basic identification information. In addition, when the digital watermark is used for the purpose of identifying a program or broadcast material at a broadcasting station, the identifier (content ID) of the moving image content, the individual identification number of the camera that shot the moving image content, the content between the broadcasting stations The identification information of the moving image content such as the transmission source broadcasting station ID at the time of delivery can be used as the basic identification information. Note that the basic identification information is preferably composed of, for example, a small number of bits of about 8 bits because the smaller the number of bits, the shorter the time required for detection.

  The related information means information related to moving image content. The related information is configured in units of a predetermined number of pixel blocks. The specific content of the related information varies depending on the use of the digital watermark. For example, when the digital watermark is used for detecting an illegal copy of the content, metadata describing attribute information such as the name of the moving image content, Alternatively, metadata describing rights information (such as a rights period) other than the name or name of the copyright holder of the moving image content can be used as related information. Further, when the digital watermark is used for the purpose of identifying a program or broadcast material at a broadcasting station, production information such as shooting date or shooting location of moving image content can be used as related information. Note that unlike the basic identification information, the related information only needs to be embedded in one embedded area, and therefore, it is preferable that the related information is composed of general-purpose data of about 40 bits, for example.

  The basic identification information embedding unit 201 repeatedly embeds basic identification information a predetermined number of times in the embedding areas (1) to (8) shown in FIG. Here, the basic identification information embedding unit 201 embeds basic identification information input from a basic identification information storage device (not shown) or the like in each of the embedding areas (1) to (8) shown in FIG. For example, when the basic identification information is 8 bits, the basic identification information embedding unit 201 embeds 8 bits of basic identification information five times for each of the embedded areas (1) to (8) shown in FIG. Embedded with a total of 40 bits of data.

  When the basic identification information embedding unit 201 embeds the basic identification information in each of the embedding areas (1) to (8) shown in FIG. 2 five times, the basic identification information is embedded in the order of the embedding areas (1) to (8). By repeating the embedding process five times, a total of 40 bits of data are embedded in one embedding area. However, the order in which the basic identification information embedding unit 201 embeds the basic identification information is not particularly limited. For example, the process of embedding the basic identification information five times in one embedding area is sequentially performed from the embedding areas (1) to (8). By performing, a total of 40 bits of data may be embedded in one embedded area.

  The related information embedding unit 202 embeds the related information input from a related information storage device (not shown) or the like once or more in the embedding areas (1) to (8) shown in FIG. For example, when the related information is 40 bits, the related information embedding unit 202 embeds 40 bits of related information once for each of the embedded regions (1) to (8) shown in FIG. Embed 40-bit data. Here, the related information embedding unit 202 performs related information embedding processing after the basic identification information embedding unit 201 embeds the basic identification information five times.

  As described above, when the basic identification information embedding unit 201 performs the basic identification information embedding process five times and then the related information embedding unit 202 performs the related information embedding process once, the embedding area shown in FIG. In each of 1) to (8), embedded digital watermark data having a data arrangement as shown in FIG. 3 is embedded. That is, as shown in FIG. 3, each of the embedding areas (1) to (8) shown in FIG. 2 becomes one embedding unit (unit embedding area), and a basic identification is made as a repetitive embedding area of a small number of bit data in the embedding unit. Information a1 to a5 is embedded, and related information b is embedded in an embedded area of general-purpose data in the embedding unit. The CRC in FIG. 3 means error correction data for the data bits of the related information b embedded in the general data embedding area.

(Digital watermark embedding algorithm)
Specifically, the basic identification information embedding unit 201 and the related information embedding unit 202 described above use the same algorithm as the algorithm described in Patent Document 1 described above, to add the basic identification information and the related information to the frame image. Embed. That is, the basic identification information embedding unit 201 and the related information embedding unit 202 apply a pixel having a characteristic that a change in pixel value (luminance value) is not easily perceived for each of the embedding regions (1) to (8) illustrated in FIG. Extract as pixels and embed basic identification information and related information by changing pixel values (luminance values) in the boundary and / or time direction between the areas, and generate digital watermark embedded moving image content with re-shooting tolerance etc. To do.

  As shown in FIG. 1, the digital watermark embedding unit 20 receives the divided image from the region dividing unit 10. Then, the digital watermark embedding unit 20 generates a digital watermark embedded moving image content by the above-described method, and outputs it to, for example, a digital watermark embedded moving image content storage unit (not shown).

  The digital watermark embedding device 1 having the above-described configuration can double the number of basic identification information that can be embedded in one frame image by the number of embedding areas. Even when severe deterioration occurs, it is possible to generate a digital watermark-embedded moving image content capable of detecting a digital watermark from basic identification information of other portions. Accordingly, the digital watermark embedding apparatus 1 repeatedly embeds the basic identification information in the frame image, so that even if a part of the frame image is deteriorated, the digital watermark detection apparatus uses the digital identification information from the other parts of the basic identification information. Therefore, illegal copies of content can be detected at high speed and efficiently eliminated, and programs or broadcast materials can be effectively identified at a broadcasting station.

[Operation of Digital Watermark Embedding Apparatus 1]
Hereinafter, the operation of the digital watermark embedding apparatus 1 will be briefly described with reference to FIG. First, when moving image content is input from a moving image content storage device or the like (not shown), the embedding unit specifying means 9 specifies a pixel block unit corresponding to one bit of the digital watermark as an embedding unit in the frame image (step) S1). Next, the area dividing means 10 generates a divided image obtained by dividing the frame image of the moving image content into a plurality of embedding areas (see FIG. 2), and outputs this to the digital watermark embedding means 20 (step S2). Next, the basic identification information embedding unit 201 repeatedly embeds the basic identification information a predetermined number of times (for example, five times) in each of the embedding areas (1) to (8) shown in FIG. 2 (step S3). Further, the related information embedding unit 202 embeds the related information once in each of the embedding areas (1) to (8) shown in FIG. 2 (step S4). Then, by such an embedding process, a digital watermark embedded moving image in which embedded data of a digital watermark having a data arrangement as shown in FIG. 3 is embedded in each of the embedding areas (1) to (8) shown in FIG. Content is generated and output to a digital watermark embedded moving image content storage means (not shown).

[Second Embodiment]
Hereinafter, a digital watermark embedding device 1A according to the second embodiment will be briefly described with reference to FIG. 5 (refer to FIG. 3 as appropriate). As shown in FIG. 5, the digital watermark embedding apparatus 1 </ b> A includes an embedding unit specifying unit 9, a digital watermark embedding unit 21, and an embedded data generating unit 30. Here, unlike the digital watermark embedding apparatus 1 described above, the digital watermark embedding apparatus 1A repeatedly embeds pre-generated embedded data in the plane of the frame image without dividing the frame image into a plurality of embedding areas. It is characterized by. The digital watermark embedding apparatus 1A uses the same embedding algorithm as the digital watermark embedding apparatus 1.

  The embedding unit specifying unit 9 specifies a pixel block unit corresponding to one bit of the digital watermark as an embedding unit in one frame image, as in the digital watermark embedding apparatus 1 described above.

  The electronic watermark embedding unit 21 embeds an electronic watermark composed of basic identification information and related information in a frame image constituting the moving image content, similar to the electronic watermark embedding unit 20 described above. 201 and the related information embedding unit 202 are different from the digital watermark embedding unit 20 in that the 201 and the related information embedding unit 202 are not provided. That is, the digital watermark embedding unit 21 does not embed the basic identification information and the related information separately in the frame image, but uses the embedded data of the digital watermark generated in advance by the embedded data generation unit 30 to be described later. Embedded repeatedly in the plane.

  As shown in FIG. 5, the digital watermark embedding unit 21 receives moving image content from a moving image content storage unit (not shown) and the like, and also receives embedded data from the embedded data generation unit 30. Then, the digital watermark embedding unit 21 generates a digital watermark embedded moving image content by the above-described method, and outputs it to, for example, a digital watermark embedded moving image content storage unit (not shown). As shown in FIG. 3, the embedded data means digital watermark embedded data having a data array including a plurality of the same basic identification information and one related information.

  The embedded data generation means 30 generates digital watermark embedded data in advance. The embedded data generating means 30 generates electronic watermark embedded data including basic identification information and related information by using one pixel block specified by the above-described embedding unit specifying means 9 as 1-bit data.

  The basic identification information is input to the embedded data generation means 30 from a basic identification information storage device or the like (not shown), and related information is input from a related information storage device or the like (not shown). Then, as shown in FIG. 3, the embedded data generating means 30 generates the embedded data of the digital watermark by arranging the basic identification information and the related information, and as shown in FIG. Output to means 21.

  Since the digital watermark embedding apparatus 1A having the above-described configuration can embed a plurality of basic identification information and one related information in a frame image at a time, the number of digital watermark embedding processes is reduced and the overall processing speed is reduced. Can be speeded up.

[Modification of Second Embodiment]
Hereinafter, a modified example of the digital watermark embedding apparatus 1A according to the second embodiment will be briefly described with reference to FIG. As shown in FIG. 5, the modified example of the electronic watermark embedding apparatus 1A has the same configuration as the above-described electronic watermark embedding apparatus 1A, but includes an embedding unit specifying means 9, an electronic watermark embedding means 21, and an embedded data generating means. 30 operations are different. Note that the modification example of the digital watermark embedding apparatus 1A uses an embedding algorithm similar to that of the digital watermark embedding apparatus 1.

  In a modification of the digital watermark embedding apparatus 1A, the embedded data generation means 30 generates one frame of digital watermark embedded data in advance. For example, the embedding data generation means 30 uses one pixel block specified by the embedding unit specifying means 9 as 1-bit data, and 8 watermarks (total 80 bits) of digital watermark embedding data having the data arrangement shown in FIG. This means that one frame of embedded data (total of 640 bits) is generated at a time. The modified example of the digital watermark embedding apparatus 1A performs the digital watermark embedding process by embedding the digital watermark embedding data for one frame generated in this way once in the frame image.

  In the modified example of the digital watermark embedding apparatus 1A having the above-described configuration, since the embedded data generation unit 30 generates embedded data for one frame, the digital watermark can be embedded in the frame image by a single process. The speed of the embedding process can be improved.

[Digital watermark embedding program]
Here, the above-described digital watermark embedding apparatuses 1 and 1A and modifications thereof can be realized by causing a general computer to operate by a program that functions as each of the above-described units and units. This program can be distributed via a communication line, or can be written on a recording medium such as a CD-ROM for distribution.

<Digital watermark detection device>
[First Embodiment]
Hereinafter, the digital watermark detection apparatus 2 according to the first embodiment will be described in detail with reference to FIG. The digital watermark detection device 2 detects a digital watermark embedded in the digital watermark embedded video content generated by the digital watermark embedding device 1 described above. Specifically, the digital watermark detection apparatus 2 electronically converts digital watermark embedded video image content in which a digital watermark including a plurality of basic identification information and one related information is embedded in a frame image constituting the video content. Detect watermarks. Then, as shown in FIG. 6, the digital watermark detection apparatus 2 outputs the detection result (the contents of the basic identification information and the related information) to the external display unit 80. The display unit 80 shown in FIG. 6 is assumed to be a monitor of a personal computer provided outside, but may be configured to be provided inside the digital watermark detection apparatus 2.

  Also, it is assumed that the digital watermark detection apparatus 2 is used when the digital watermark is used for the purpose of detecting an illegal copy of content. Accordingly, the digital watermark to be detected by the digital watermark detection apparatus 2 includes information for identifying the copyright holder of the moving image content such as the name or name of the copyright holder as basic identification information. In addition, as related information, metadata describing attribute information such as the name of the moving image content, or metadata describing rights information (right period, etc.) other than the name or name of the copyright holder of the moving image content Is assumed.

  As shown in FIG. 6, the digital watermark detection apparatus 2 includes a digital watermark detection unit 70 as a main configuration, and includes a search keyword input unit 40, a moving image content collection unit 50, and a moving image content storage unit 60. Are provided as additional configurations. Hereinafter, each component provided in the digital watermark detection apparatus 2 will be described.

  The search keyword input unit 40 is for inputting a search keyword to the moving image content collection unit 50. Specifically, the search keyword input unit 40 searches for moving image content existing on a preset website on the communication network N as shown in FIG. 6 based on an operation of an external user (not shown). The search keyword is input to the moving image content collection means 50. Note that the Internet is assumed here as the communication network N. In addition, as a preset website, a video posting site or the like is assumed here.

  The moving image content collection unit 50 collects moving image content. Specifically, as shown in FIG. 6, the moving image content collection means 50 searches for moving image content existing on a preset website on the communication network N according to the search keyword, and the moving image content To collect.

  The moving image content storage unit 60 stores the moving image content collected by the moving image content collection unit 50. Specifically, the moving image content storage unit 60 is implemented by a memory, a hard disk, or the like that can store data. As shown in FIG. 6, moving image content storage means 60 receives moving picture content image data (luminance and color difference image data) from moving picture content collection means 50 in units of one frame or a plurality of frames.

  The digital watermark detection means 70 is for detecting a digital watermark from frame images constituting the moving image content. Specifically, as shown in FIG. 6, the electronic watermark detection means 70 includes a basic identification information detection unit 701 that detects basic identification information from a frame image, and a related information detection unit 702 that detects related information from the frame image. The basic identification information embedded in the frame image as a digital watermark and the related information are separately detected.

  The basic identification information detection unit 701 detects basic identification information embedded in the embedded regions (1) to (8) shown in FIG. For example, the basic identification information detection unit 701 sequentially scans from the embedding area (1) to the embedding area (8) illustrated in FIG. 2 to determine an embedding bit for each embedding area, and as described later, The final embedded bit corresponding to the basic identification information is determined by making a complementary determination by majority determination or the like that determines the majority of the determination results. Note that the basic identification information detection unit 701 indicates what basic identification information is embedded at which position of the frame image by the digital watermark embedding device 1, that is, information on the embedded position of the basic identification information to be detected, The information of the embedded bit corresponding to the basic identification information is stored in advance, and the final embedded bit is determined by determining the embedded bit using the information.

  Here, in each of the embedding areas (1) to (8) shown in FIG. 2, five pieces of basic identification information are embedded as shown in FIG. Basic identification information is embedded in 40 locations. Therefore, since the basic identification information can be detected from a frame image having a smaller number of frames, the digital watermark detection process can be speeded up.

  The related information detection unit 702 detects related information embedded in the embedded areas (1) to (8) shown in FIG. For example, the related information detection unit 702 sequentially scans from the embedding area (1) to the embedding area (8) illustrated in FIG. 2 to determine the embedding bit for each embedding area, and the plurality of determinations as described later. The final embedded bit corresponding to the related information is determined by making a complementary decision by majority decision or the like for majority decision of the result. Note that the related information detection unit 702 indicates what type of related information is embedded in which position of the frame image by the digital watermark embedding apparatus 1, that is, information on the embedded position of related information to be detected, and the related information. The embedded bit information corresponding to is stored in advance, and the final embedded bit is determined by determining the embedded bit using this information.

  Here, each of the embedding areas (1) to (8) shown in FIG. 2 has one piece of related information embedded therein as shown in FIG. The relevant information is embedded in the place. Here, the related information detection unit 702 performs related information detection processing after the basic identification information detection processing by the basic identification information detection unit 701 described above.

(Digital watermark detection algorithm)
The basic identification information detection unit 701 and the related information detection unit 702 detect basic identification information and related information in a frame image using the following algorithm. When the basic identification information detection unit 701 and the related information detection unit 702 perform the digital watermark embedding process using the algorithm described in Patent Document 1 as described above, for example, the embedded regions (1) to (8) ( 2) and / or temporal direction pixel value (brightness value) change patterns and embedded bit embedding areas (1) to (8) (see FIG. 2) and / or temporal direction. The correlation value with the pixel value (luminance value) change pattern is calculated to determine the bit for each embedding area, and the final embedding bit is determined by many of these results.

  As shown in FIG. 6, moving image content is input from the moving image content storage unit 60 to the digital watermark detection unit 70. Then, the digital watermark detection means 70 detects the digital watermark by the above-described method, and outputs the detection result to the display means 80 as shown in FIG.

  In the digital watermark detection apparatus 2 having the above configuration, the basic identification information detection unit 701 detects basic identification information from a plurality of embedding areas, and the related information detection unit 702 detects related information from the plurality of embedding areas. As described above, the detection process can be performed in two stages. Further, the digital watermark detection apparatus 2 has a frame image in order to detect whether or not basic identification information or related information is embedded in a plurality of embedded regions of the frame image constituting the moving image content that matches the keyword. Even when deterioration occurs in a part, a digital watermark can be detected from basic identification information or related information of another part. Therefore, the digital watermark detection apparatus 2 detects the digital watermark from the basic identification information of other parts even when a part of the frame image deteriorates because the basic identification information is repeatedly embedded in the frame image. Therefore, illegal copies of content can be detected at high speed and efficiently eliminated, and programs or broadcast materials can be effectively identified at a broadcast station.

[Operation of Digital Watermark Detection Apparatus 2]
Hereinafter, the operation of the digital watermark detection apparatus 2 will be briefly described with reference to FIG. First, when a search keyword is input from the search keyword input unit 40, the moving image content collection unit 50 searches for moving image content existing on a preset website on the communication network N according to the search keyword. Collect (step S5). Next, the basic identification information detection unit 701 detects and detects the basic identification information embedded in the embedded areas (1) to (8) (see FIG. 2) of the frame images constituting the collected moving image content. The result is output to the display means 80 (step S6). Next, the related information detection unit 702 detects the related identification information embedded in the embedded regions (1) to (8) (see FIG. 2) of the frame image constituting the collected moving image content, and the detection result Is output to the display means 80 (step S7). Then, the display unit 80 displays the detection result.

[Second Embodiment]
Hereinafter, a digital watermark detection apparatus 2A according to the second embodiment will be briefly described with reference to FIG. The digital watermark detection apparatus 2A detects the digital watermark embedded in the digital watermark embedded moving image content generated by the digital watermark embedding apparatus 1 in the same manner as the digital watermark detection apparatus 2 described above. In addition to the moving image content storage unit 60 and the digital watermark detection unit 70, a moving image content receiving unit 90, a moving image content decoding unit 100, a first database storage unit 111, and a second database storage unit 112 are provided. However, the digital watermark detection apparatus 2 is different from the digital watermark detection apparatus 2. The digital watermark detection apparatus 2A uses the same detection algorithm as the digital watermark detection apparatus 2.

  Also, it is assumed that the digital watermark detection apparatus 2A is used when the digital watermark is used for the purpose of identifying a program or broadcast material in a broadcasting station. Therefore, in the digital watermark to be detected by the digital watermark detection apparatus 2A, as the basic identification information, the identifier (content ID) of the moving image content, the individual identification number of the camera or the like that shot the moving image content, and between broadcast stations Includes the identification information of the moving image content such as the transmission source broadcasting station ID at the time of delivering the content, and the related information includes the production information such as the shooting date and time or the shooting location of the moving image content. Assume the case.

  The moving image content receiving unit 90 receives moving image content (hereinafter referred to as “compressed moving image content”) subjected to compression processing via a transmission path. The moving image content receiving unit 90 outputs the compressed moving image content received via the transmission path T to the moving image content decoding unit 100 as shown in FIG. Here, the transmission path T is assumed to be an FPU (Field Pickup Unit) line, a high-speed fixed data communication line, the Internet, or the like connecting between broadcasting stations. Also, the moving image content compression processing is illustrated with respect to the electronic watermark embedded moving image content after the electronic watermark embedding device 1 or 1A has performed the electronic watermark embedding processing in the transmitting broadcast station, for example. This means that the compression process has been performed by a non-compressor.

  The moving image content decoding unit 100 decodes moving image content into a baseband signal. As shown in FIG. 8, the moving image content decoding unit 100 receives the compressed moving image content subjected to the compression processing from the moving image content receiving unit 90 and decodes it into a baseband signal, thereby performing the pre-compression processing. Returning to the state, the moving image content is output to the moving image content storage means 60.

  The first database storage unit 111 stores the name of the moving image content or the description of the moving image content as text information in association with the basic identification information of the moving image content. Specifically, the first database storage unit 111 is implemented by a memory, a hard disk, or the like that can store data. As shown in FIG. 8, the first database storage unit 111 outputs the name of the moving image content corresponding to the basic identification information or text information such as a description of the moving image content to the basic identification information detection unit 701.

  The second database storage unit 112 stores the map information of the place where the moving image content is photographed as text information in association with the related information of the moving image content. Specifically, the second database storage unit 112 is implemented by a memory, a hard disk, or the like that can store data. As shown in FIG. 8, the second database storage unit 112 outputs text information including map information of a place where the moving image content corresponding to the related information is taken to the related information identification unit 702.

  In the digital watermark detection apparatus 2A having such a configuration, the basic identification information detection unit 701 of the digital watermark detection unit 70 includes a plurality of embeddings in a frame image constituting the moving image content decoded by the moving image content decoding unit 100. The basic identification information is detected from the area (see FIG. 2), and the name of the moving image content corresponding to the basic identification information or the text information such as the description of the moving image content is extracted from the first database storage unit 111. To do. In addition, the related information detection unit 702 of the digital watermark detection unit 70 detects related information from a plurality of embedded regions (see FIG. 2) in the frame image constituting the moving image content decoded by the moving image content decoding unit 100. At the same time, text information such as map information of the place where the moving image content corresponding to the related information is taken is extracted from the second database storage unit 112.

  When the digital watermark detection apparatus 2A having the above-described configuration receives the moving image content via the transmission path T, in addition to the detection of the basic identification information and the related information, information related thereto is also extracted. For example, even when a moving image content with an unknown transmission source or name is received, the transmission source or name can be recognized.

[Operation of Digital Watermark Detection Apparatus 2A]
Hereinafter, the operation of the digital watermark detection apparatus 2A will be briefly described with reference to FIG. First, the moving image content receiving means 90 receives the compressed moving image content via the transmission path T (step S8). Next, the moving image content decoding unit 100 decodes the compressed moving image content into a baseband signal (step S9). Next, the basic identification information detection unit 701 detects the basic identification information embedded in the embedding areas (1) to (8) (see FIG. 2) of the frame image constituting the decoded moving image content, Text information corresponding to the basic identification information is extracted from the first database storage unit 111, and the detection result and the text information are output to the display unit 80 (step S10). Next, the related information detection unit 702 detects the related identification information embedded in the embedded regions (1) to (8) (see FIG. 2) of the frame images constituting the collected moving image content, and (2) Text information corresponding to the related information is extracted from the database storage unit 112, and the detection result and the text information are output to the display unit 80 (step S11). Then, the display unit 80 displays the detection result and text information.

[Digital watermark detection program]
Here, the digital watermark detection devices 2 and 2A described above can be realized by causing a general computer to operate by a program that functions as each of the above-described units and units. This program can be distributed via a communication line, or can be written on a recording medium such as a CD-ROM for distribution.

  As mentioned above, the digital watermark embedding device, the digital watermark embedding program, the digital watermark detection device, and the digital watermark detection program according to the present invention have been described in detail according to the mode for carrying out the invention. The present invention should not be limited to the above, but should be widely interpreted based on the description of the scope of claims. Needless to say, various changes and modifications based on these descriptions are also included in the spirit of the present invention.

  For example, the digital watermark embedding unit 20 of the digital watermark embedding apparatus 1 may include only the basic identification information embedding unit 201. That is, the digital watermark embedding device 1 may generate the digital watermark embedded video content by embedding only basic identification information in the input video content.

  Further, as shown in FIG. 2, the area dividing unit 10 of the digital watermark embedding apparatus 1 divides the frame image into eight areas (1) to (8). You may divide | segment into the above area | region.

  Further, the basic identification information embedding unit 201 of the digital watermark embedding apparatus 1 may embed basic identification information only once in each of the embedding areas (1) to (8) shown in FIG.

  The related information embedding unit 202 of the digital watermark embedding apparatus 1 performs the related information embedding process after the basic identification information embedding unit 201 embeds the basic identification information five times. The order of embedding the related information is not particularly limited, which may be first, later, or simultaneous.

  Further, the basic identification information embedding unit 201 and the related information embedding unit 202 of the digital watermark embedding device 1 are described in Patent Document 1 if a digital watermark having a data arrangement as shown in FIG. 3 can be embedded. An algorithm other than the digital watermark embedding algorithm having reshooting resistance can also be used.

  The embedded data generating means 30 of the digital watermark embedding apparatus 1A described above may be configured to generate digital watermark embedded data including only basic identification information. That is, the digital watermark embedding device 1A may generate digital watermark embedding data that does not include related information.

  Further, the embedded data generating means 30 of the digital watermark embedding apparatus 1A may be configured to generate digital watermark embedded data including only one basic identification information. That is, the digital watermark embedding apparatus 1A may generate digital watermark embedding data including only one basic identification information or one basic identification information and one related information.

  Also, the digital watermark detection devices 2 and 2A detect not only the digital watermark embedding device 1 but also the digital watermark embedded in the digital watermark embedding moving image content generated by the digital watermark embedding device 1A and its modification. You can also.

  Further, the digital watermark detection algorithm used in the basic identification information detection unit 701 and the related information detection unit 702 of the digital watermark detection devices 2 and 2A is not limited to the above, and for example, for each embedded region in the frame image An algorithm may be used in which the calculated correlation values are sequentially added and the corresponding embedded bits are output as final embedded bits when a certain threshold value is reached. In this case, unlike the case where, for example, one basic identification information is embedded in the time direction of a frame image or over a plurality of frames, the basic identification information can be detected from one frame image. Detection processing can be speeded up.

  In addition, the related information detection unit 702 of the above-described digital watermark detection devices 2 and 2A performs the related information detection processing after the basic identification information detection processing by the basic identification information detection unit 701. Depending on the processing capacity of 2 or 2A, the detection processing of the basic identification information and the detection processing of the related information may be performed simultaneously in parallel.

  Further, in the description of the digital watermark embedding apparatus 1 described above, there is a case where the 8-bit basic identification information is repeatedly embedded in the repetitive embedding area of the small number of bits data shown in FIG. Although shown, other bit string lengths may be used. Which bit string length is optimal for the two types of data depends on the time required for detection of the digital watermark and the detection accuracy, and therefore differs depending on each specific mode.

  For example, when it is necessary to further shorten the time required for detecting the basic identification information, the number of embedding repetitions may be increased. For example, when the number of repetitions of the basic identification information in the digital watermark data array shown in FIG. 3 is increased from 5 to 10, the number of embedded bits for each embedded area determined by the basic identification information detecting unit 701 increases. Since the time until the final embedded bit is determined is further shortened, the basic identification information can be detected at a higher speed. If the amount of related information (general-purpose data) is large and it takes a very long time to detect it, general-purpose data in the embedding area in one frame occupies by reducing the number of repetitions of embedding basic identification information. What is necessary is just to increase a ratio.

  In the description of the digital watermark detection apparatus 2 described above, there is a possibility of copyright infringement, such as a broadcast program uploaded to a video posting site, among moving image contents accessible by the moving image content collection unit 50 via the Internet. Although the case of collecting suspected moving image content has been shown, the communication network N to be used is not limited to the Internet, and any communication network can be used. As for the website, the moving image content may be searched not only for the moving image posting site but also for any website, and any accessible moving image content may be collected.

  Further, an illegal distribution countermeasure system may be constructed by combining the digital watermark detection apparatus 2 described above with a deletion request system for moving image posting sites. In addition, the digital watermark detection apparatus 2 is directly provided in a video posting site, and by quickly detecting basic identification information from uploaded video content, illegally uploaded video content can be detected quickly and immediately. It is good also as a structure which deletes this.

DESCRIPTION OF SYMBOLS 1,1A Digital watermark embedding apparatus 2,2A Digital watermark detection apparatus 9 Embedding unit specification means 10 Area division means 20, 21 Digital watermark embedding means 30 Embedded data generation means 40 Search keyword input means 50 Moving picture content collection means 60 Moving picture contents Storage means 70 Digital watermark detection means 80 Display means 90 Moving picture content receiving means 100 Moving picture content decoding means 111 First database storage means (DB1)
112 Second database storage means (DB1)
201 Basic identification information embedding unit 202 Related information embedding unit 701 Basic identification information detecting unit 702 Related information detecting unit N Communication network T Transmission path

Claims (14)

A digital watermark embedding device that generates a digital watermark embedded video content by embedding a digital watermark in the video content,
An embedding unit specifying means for specifying a pixel block unit corresponding to one bit of a digital watermark as an embedding unit in a frame image constituting the moving image content;
A digital watermark embedding unit that embeds a digital watermark including one or more basic identification information, which is configured in units of a predetermined number of pixel blocks and is used for distinguishing the moving image content from other moving image content, in the frame image; ,
Area dividing means for dividing the frame image into a plurality of embedded areas,
The digital watermark embedding apparatus comprising: a basic identification information embedding unit that embeds the basic identification information at least once for each of the plurality of embedding areas. A digital watermark embedding device that generates a digital watermark embedded video content by embedding a digital watermark in the video content,
An embedding unit specifying means for specifying a pixel block unit corresponding to one bit of a digital watermark as an embedding unit in a frame image constituting the moving image content;
A digital watermark embedding unit that embeds a digital watermark including one or more basic identification information, which is configured in units of a predetermined number of pixel blocks and is used for distinguishing the moving image content from other moving image content, in the frame image; ,
Embedded data generation means for generating embedded data of the digital watermark including one or more of the same basic identification information,
The digital watermark embedding device, wherein the digital watermark embedding unit repeatedly embeds the embedded data in the frame image a predetermined number of times.   The digital watermark according to claim 1, wherein the digital watermark embedding unit includes a related information embedding unit that embeds related information, which is information related to moving image content, at least once for each of the plurality of embedding areas. Implantation device.   The embedded data generation unit generates the embedded data of the digital watermark including one or more pieces of the same basic identification information and one or more pieces of related information that is information related to moving image content. Item 3. The electronic watermark embedding device according to Item 2.   The digital watermark embedding apparatus according to claim 3 or 4, wherein the basic identification information is a name or a name of a copyright holder of the moving image content.   5. The digital watermark embedding apparatus according to claim 3, wherein the basic identification information is an identifier of the moving image content.   The related information describes metadata describing the name of the moving image content, rights information other than the name of the copyright owner of the moving image content, or rights information other than the name of the copyright owner of the moving image content The digital watermark embedding apparatus according to any one of claims 3 to 5, wherein the digital watermark embedding apparatus includes the metadata.   7. The digital watermark embedding apparatus according to claim 3, wherein the related information is information indicating a shooting date / time or a shooting location of the moving image content. In order to generate a digital watermark embedded video content by embedding the digital watermark in the video content,
An embedding unit specifying means for specifying a pixel block unit corresponding to one bit of an electronic watermark serving as an embedding unit in a frame image constituting the moving image content;
An electronic watermark embedding unit that embeds an electronic watermark that is configured in units of a predetermined number of pixel blocks in the frame image and includes one or more basic identification information that is information for distinguishing the moving image content from other moving image content;
Function as area dividing means for dividing the frame image into a plurality of embedded areas;
The electronic watermark embedding program, comprising: a basic identification information embedding unit that embeds the basic identification information at least once for each of the plurality of embedding areas. In order to generate a digital watermark embedded video content by embedding the digital watermark in the video content,
An embedding unit specifying means for specifying a pixel block unit corresponding to one bit of an electronic watermark serving as an embedding unit in a frame image constituting the moving image content;
An electronic watermark embedding unit that embeds an electronic watermark that is configured in units of a predetermined number of pixel blocks in the frame image and includes one or more basic identification information that is information for distinguishing the moving image content from other moving image content;
Function as embedded data generation means for generating embedded data of the digital watermark including one or more of the same basic identification information,
The digital watermark embedding unit, wherein the digital watermark embedding unit repeatedly embeds the embedded data in the frame image a predetermined number of times. Each of the plurality of embedded regions in the frame image constituting the moving image content includes one or more basic identification information that is information for distinguishing the moving image content from other moving image contents, and the moving image content includes The digital watermark embedding device according to any one of claims 1 to 10, wherein the digital watermark embedding moving image content is embedded with a digital watermark including one or more related information that is related information . An electronic watermark detection apparatus for detecting the electronic watermark,
A digital watermark detection means comprising: a basic identification information detection unit that detects the basic identification information from the plurality of embedded regions; and a related information detection unit that detects the related information from the plurality of embedded regions ,
The basic identification information detection unit and the related information detection unit determine embedded bits for each of a plurality of embedded regions in a frame image constituting the moving image content, and determine the plurality of determination results in a complementary manner. the electronic watermark detection apparatus characterized that you determine the final buried bit corresponding to the basic identification information and the related information. Search keyword input means for inputting a search keyword for searching for moving image content existing on a website set in advance on a communication network;
Moving image content collection means for searching for moving image content existing on the website according to the search keyword and collecting the moving image content;
The basic identification information detection unit and the related information detection unit detect the basic identification information and the related information from a plurality of embedded regions in a frame image constituting the collected moving image content. The digital watermark detection apparatus according to claim 11. Moving image content receiving means for receiving the moving image content via a transmission path;
Moving image content decoding means for decoding the received moving image content into a baseband signal;
First database storage means for storing the name of the moving image content or the description of the moving image content as text information in association with the basic identification information of the moving image content;
Second database storage means for storing, as text information, map information of a place where the moving image content is photographed in association with the related information of the moving image content,
The basic identification information detection unit and the related information detection unit detect the basic identification information and the related information from a plurality of embedded regions in a frame image constituting the decoded moving image content. 12. The digital watermark detection apparatus according to claim 11, wherein text information corresponding to the basic identification information and the related information is extracted from a database storage unit and the second database storage unit, respectively. Each of the plurality of embedded regions in the frame image constituting the moving image content includes one or more basic identification information that is information for distinguishing the moving image content from other moving image contents, and the moving image content includes The digital watermark embedding device according to any one of claims 1 to 10, wherein the digital watermark embedding moving image content is embedded with a digital watermark including one or more related information that is related information . In order to detect the watermark, a computer is
A basic identification information detection unit for detecting the basic identification information from the plurality of embedding areas; and a related information detection unit for detecting the related information from the plurality of embedding areas.
The basic identification information detection unit and the related information detection unit determine embedded bits for each of a plurality of embedded regions in a frame image constituting the moving image content, and determine the plurality of determination results in a complementary manner. digital watermark detection program characterized that you determine the final buried bit corresponding to the basic identification information and the related information.

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