JP2002369160A - Apparatus for electronic watermark embedding process, method for embedding electronic watermark, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To constitute an embedding process for an electronic watermark which is made difficult to recognize based on the motion information of moving images in electronic watermark embedding. SOLUTION: Motion detection on a timely continuous inputted digital video signal is conducted by using a frame correlation. Based on the detected motion information, when an image is moving at such a speed that human eyes cannot recognize a still pattern, the electronic watermark is kept still, and when the image is moving at such a speed that human eyes can recognize a still pattern, the electronic watermark is also moved following the image. Thereby, the electronic watermark can be superimposed on the inputted digital video signal highly efficiently by adaptively reducing the calculation quantity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for embedding or reading additional information such as copyright information and editing information in data of an image or the like. The present invention relates to a digital watermark embedding processing apparatus, a digital watermark embedding processing method, and a program that execute processing for embedding (watermark: also referred to as Digital Watermarking or DataHiding).

[0002]

2. Description of the Related Art With the advancement of digital technology, digital recording / reproducing apparatuses that do not cause image quality deterioration and sound quality deterioration due to repeated execution of recording and reproduction processing have become widespread.
Various digital and digital contents such as music, DVD,
It can be distributed and distributed through media such as CDs or networks.

In digital recording / reproducing, unlike analog recording / reproducing, data deterioration does not occur even if recording / reproducing processing is repeatedly executed, so that the same quality as original data is maintained. The spread of such digital recording / reproducing technology has resulted in the proliferation of illegal copying, and is a serious problem from the viewpoint of copyright protection.

In order to cope with copyright infringement due to unauthorized duplication (copy) of digital content, copy control information for copy control is added to the digital content,
There has been proposed a configuration in which duplication control information is read at the time of recording and reproduction of content, and a process according to the read control information is executed to prevent unauthorized duplication.

There are various modes of content copy control. For example, as a typical method, CGMS (Copy
Generation Management Sys
tem; copy generation management
System) system. In the CGMS method, if an analog video signal (referred to as CGMS-A), a specific horizontal section within a vertical blanking period of the luminance signal,
For example, in the case of an NTSC signal, two bits of the 20-bit additional information to be superimposed on the effective video portion in the twentieth horizontal section are superimposed as duplication control information, and a digital video signal (referred to as CGMS-D). ), The transmission method includes 2-bit information for duplication control as additional information to be inserted and added to digital video data.

The meaning of 2-bit information (hereinafter referred to as CGMS information) in the case of the CGMS system is [00]
... Duplicatable [10]... Duplicate once (only one generation can be duplicated) [11]... Duplicate prohibited (absolute duplicate prohibited).

The above-mentioned CGMS system is an example of a typical copy control system, and there are various other systems for protecting the copyright of contents. For example, in digital broadcasting performed by a broadcasting station, program sequence information (S) included in a transport stream (TS) packet constituting digital data.
There is a method in which a digital copy control descriptor (Digital Copy Control Descriptor) is stored in I: Service Information, and the copy generation control according to the descriptor is performed when data received by the receiving device is recorded in the recording device.

However, the above-mentioned control information is added as bit data to, for example, a header of the content, and it is difficult to completely eliminate the possibility of falsification of the added data. An advantageous configuration in terms of eliminating the possibility of data tampering is a digital watermark. Digital watermarks (watermarks) are difficult to see or perceive during normal content (image data or audio data) playback, and detection and embedding of digital watermarks can only be performed by executing a specific algorithm or processing by a specific device. It becomes possible. By detecting a digital watermark (watermark (WM)) at the time of content processing in a receiver, a recording / reproducing device, and the like, and performing control in accordance with the digital watermark, control with higher reliability can be performed.

[0009] The copyright protection method using a digital watermark (watermark (WM)) for a recording medium such as an optical disk or a content transmitted from a broadcasting station or the like via a medium such as a satellite wave, a terrestrial wave, or a cable is disclosed. In addition, a modulation signal or the like of data relating to copyright is superimposed and recorded on a video signal, an audio signal, or the like at a very small signal level that does not affect reproduction of a video signal or an audio signal. In the age of digital networks where various digital contents such as images, sounds, and data can be copied and distributed without deterioration, digital watermarking technology protects copyrights by embedding information in the contents themselves. It is a powerful technology that can do.

Digital watermark (watermark (WM))
The information embedded in the content is not limited to the above-described copy control information, and various information such as the copyright information of the content, the content processing information, the content configuration information, the content processing information, the content editing information, and the content reproduction processing method. Can be embedded. For example, the editing information is embedded at the time of editing the content, and in each editing step, the processing step is confirmed by referring to the digital watermark. For example, such editing information is embedded in the content as a new digital watermark in the content at each editing step, and is finally removed from the content.

Various techniques have been proposed for embedding and detecting a digital watermark in data. One typical digital watermark embedding detection mode includes a method based on data as an original signal, for example, a statistical property of an image. A method for embedding a digital watermark based on PN sequence random number data as a basic pattern based on the statistical properties of an image signal such as a digital video signal will be described. For simplicity, the frame data of the luminance signal has a horizontal size of 8 pixels and a vertical size of 6 pixels.

First, PN sequence random number data PN is set as in the following equation.

[0013]

(Equation 1)

The random number data PN is generated so that the total sum is statistically zero. Next, the embedded information DC is spectrum-spread by random number data PN having the property as shown in the above equation. That is, the polarity of the embedded information DC is “1”.
In the case of, by using the pattern of the random number data PN as it is, the digital watermark pattern WM is represented by the following equation.

[0015]

(Equation 2)

When the polarity of the embedding information DC is "0", the digital watermark pattern WM is expressed by the following equation by using a pattern obtained by inverting the pattern of the random number data PN.

[0017]

(Equation 3)

When the embedding information DC is composed of a plurality of information bits, for example, the frame data of the luminance signal may be divided into appropriate small areas, and each information bit may correspond to each small area. Also, for example, using a plurality of different digital watermark patterns that are orthogonal to each other,
What is necessary is just to make each information bit correspond to each digital watermark pattern. Further, these techniques may be used in combination.

On the other hand, in an image signal such as a digital video signal, it is assumed that frame data DV1 indicating a luminance signal pixel value of certain frame data is represented by the following equation.
In addition, in the image signal of the digital video signal, there is a property that adjacent luminance signals have similar pixel values,
The values of adjacent pixels are set to approximate values.

[0020]

(Equation 4)

The embedding of the digital watermark is realized by adding a digital watermark pattern WM to the frame data DV1 of the luminance signal. When the polarity of the digital watermark embedding information DC is “1”, the digital watermark pattern WM shown in the above [Equation 2] is added to the luminance signal shown in the above [Equation 4]. Is embedded, the frame data DV2 of the luminance signal is data represented by the following equation.

[0022]

(Equation 5)

From the frame data DV2 of the luminance signal in which the digital watermark is embedded in this manner, the embedded information DC
Is detected, random number data PN of the same PN sequence as at the time of embedding is used. First, the inner product value P1 of the frame data DV1 of the original luminance signal and the random number data PN has a value represented by the following equation.

[0024]

P1 = DV1 · PN = 1

From the statistical properties of the image signal, the inner product P
1 is a value near 0. On the other hand, the frame data DV2 of the luminance signal in which the digital watermark is embedded and the random number data P
The inner product value P2 with N indicates that the polarity of the embedded information DC is “1”.
Has a value represented by the following equation.

[0026]

P2 = DV2 · PN = (DV1 + WM) · PN = (DV1 + PN) · PN = P1 + PN ² = 1 + 48

On the other hand, when the polarity of the embedded information DC is "0", it has a value represented by the following equation.

[0028]

[Equation 8] P2 = DV2 · PN = (DV1 + WM) · PN = (DV1-PN) · PN = P1-PN 2 = 1-48

[0029] That is the absolute value of the inner product value P2 is a inner product value PN ² near the value of the random number data PN itself. The inner product value P of the frame data DV1 of the original luminance signal and the random number data PN
1 and the inner product value P2 of the frame signal DV2 of the luminance signal in which the digital watermark is embedded and the random number data PN are calculated for various images, the distribution of the inner product values P1 and P2 is represented by a probability density function as shown in FIG. Can be expressed. Therefore, by setting an appropriate non-negative threshold value TH, it is possible to determine the presence / absence and polarity of a digital watermark as described below.

[0030]

P2 ≦ −TH: With digital watermark (polarity 0) | P2 | <TH: Without digital watermark P2 ≧ TH: With digital watermark (polarity 1)

As shown in the above equation, from the frame data DV2 of the luminance signal in which the digital watermark is embedded, the embedded information DC
Can be detected.

In realizing a digital watermark, two important points are reliability of digital watermark detection and influence of the digital watermark on image quality. In order to accurately determine the presence or absence of a digital watermark, a threshold TH that accurately separates the probability density function in the case of “with digital watermark” and the probability density function in the case of “without digital watermark” in FIG. 1 is used.
Must be set. In practice, however, the tails of the probability density functions overlap, and it is difficult to select a threshold value TH that can accurately determine the presence or absence of a digital watermark. The probability of being determined as “with digital watermark” even though the digital watermark is not embedded is particularly called False Positive, and an extremely small False Positive value is required to guarantee sound content distribution. Therefore, in order to improve the reliability of digital watermark detection,
A process of increasing the embedding strength of the digital watermark using the non-negative scalar amount C is executed. The frame data DV2 of the luminance signal when the digital watermark is embedded by increasing the digital watermark embedding strength using the scalar amount C has a value represented by the following equation.

[0033]

## EQU10 ## DV2 = DV1 + CWM

The inner product value P2 of the frame data DV2 of the luminance signal in which the digital watermark is embedded and the random number data PN may be made sufficiently large. Specifically, the frame data DV2
Has a value represented by the following equation.

[0035]

P2 = DV2 · PN = (DV1 + CWM) · PN = (DV1 ± CPN) · PN = P1 ± CPN ²

However, when the embedding strength of the digital watermark is increased in this way, the effect of the digital watermark on the image quality cannot be ignored. There is a trade-off between the reliability of digital watermark detection and the effect of digital watermark on image quality.

Image format conversion, digital-analog conversion, MPE
Even when various attacks such as G compression, filtering, clipping, resizing, and rotation are performed, the embedded digital watermark information must be correctly detected. Anyone who attempts to unfairly infringe on copyrights could maliciously attack these images with embedded watermarks. Therefore, various techniques have been proposed to enhance the resistance to these attacks and ensure the reliability of digital watermark detection. However, a digital watermarking technique that is robust against all kinds of attacks has not yet been developed, and urgent countermeasures are desired.

FIG. 2 is a diagram for explaining a mode in which copy control information is embedded in data using a digital watermark and copy control is performed by detecting a digital watermark.

Digital video signal D which is a video source
V is transmitted from a broadcasting station or the like via a medium such as a satellite wave, a terrestrial wave, or a cable.
When 0, digital watermark information DC is added and transmitted. The digital watermark information DC to be embedded here is composed of copyright information of a video source and the like, and has information of “Copy Once” (copy once).

As described above, “Copy Once” (1
Among the digital video signals transmitted with the information of “copy once” embedded in the digital watermark, the digital video signal to be received and reproduced by the set-top box or the like is used to convert the reproduced digital video signal into a digital watermark incorporated in the recording device 2. The digital watermark information DC embedded by the detection device 3 is detected.

When the digital watermark detecting device 3 built in the recording device 2 detects the digital watermark information “Copy Once”, the digital watermark rewriting device 4 built in the recording device 2 rewrites the digital watermark information DC and rewrites the optical disk 5. Etc. The digital watermark information DC to be rewritten here is composed of the copyright information of the video source, etc.
re Copy "(copy prohibited).

When the optical disk 5 copied and recorded by the recording device 2 in this manner is provided, for example, as a medium distributed on the market, the provided copy recorded optical disk 5
When the digital watermark is copied again in the recording device 6, the digital watermark information DC embedded therein is detected from the digital video signal reproduced by the digital watermark detection device 3 built in the recording device 6.

In this case, the digital watermark information DC is information of “No More Copy” which does not permit duplication, and the recording device 6 performs processing according to “No More Copy”, that is, reproduces the digital video signal on the optical disc. Stop recording at 7. Thus, the copy generation is managed.

The digital watermark embedding processing device 100
When manufacturing an optical disc 8 storing a digital video signal DV as a video source, "Never Co."
It is assumed that a process of adding digital watermark information DC having information of “py” (copy prohibition) to the optical disk 8 or the like and executing the process is performed.

When the optical disk 8 recorded as described above is distributed to the market, the provided optical disk 8
Is reproduced by the recording device 6 and is to be copied to another recording medium, the digital watermark detection device 3 incorporated in the recording device 6 detects the embedded digital watermark information DC from the reproduced digital video signal.

In this case, the digital watermark information DC is information of “Never Copy” (copy prohibited) for which copying is not permitted, and the recording device 6 transmits the “Never Copy”.
The processing according to y ″, that is, the recording of the reproduced digital video signal on the optical disk 7 is stopped.

In order to minimize the influence of the digital watermark on the image quality while securing the reliability of the digital watermark detection, a method of embedding the digital watermark by effectively utilizing the visual characteristics of human beings has been proposed. These methods take into account the human visual characteristics, redistribute the digital watermark pattern in the image, make the digital watermark pattern follow the movement of the image, and so on, without changing the overall embedding strength. The effect of watermark on image quality is effectively suppressed. The human eye is sensitive to changes in a low frequency region such as a flat portion, but is insensitive to changes in a high frequency region such as an edge portion. By using this to redistribute the digital watermark pattern from a flat portion that is conspicuous to an edge portion that is not conspicuous, it is possible to suppress the influence on the image quality of the digital watermark while securing the reliability of the digital watermark detection. When the image is stationary, the digital watermark pattern is also stopped, and when the image is moving, the digital watermark pattern is also moved, thereby embedding a digital watermark so that it is difficult for human eyes to perceive. be able to.

Motion detection is based on the international standard MPEG2 (Moving Picture Explorer) for video coding.
ts Group-2), sampling rate conversion, and the like. However, a suitable motion detection method applied to superimposition of a digital watermark has not yet been proposed.
It is desired to realize an effective motion detection method and suppress the influence of the digital watermark on the image quality.

[0049]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and performs a motion detection when embedding a digital watermark in an image while ensuring the reliability of the digital watermark detection. It is an object of the present invention to provide a digital watermark embedding processing device, a digital watermark embedding processing method, and a program, which can embed a digital watermark so as to be hardly perceived by human eyes.

More specifically, by adjusting the digital watermark pattern optimally according to the still or operating state of the image, it becomes difficult for human eyes to detect the digital watermark while ensuring the reliability of the detection. It is an object of the present invention to provide a digital watermark embedding processing apparatus, a digital watermark embedding processing method, and a program that can embed a digital watermark in such a manner.

[0051]

SUMMARY OF THE INVENTION A first aspect of the present invention is as follows.
An electronic watermark embedding processing device for executing an electronic watermark embedding process on an image signal, an electronic watermark pattern generating means for generating an electronic watermark pattern based on the embedding information, and A motion detection unit that acquires a motion vector and outputs motion information based on the motion vector;
A signal modulation unit that executes a modulation process for changing an embedding intensity on the digital watermark pattern generated by the digital watermark pattern generation unit in accordance with a speed corresponding value indicated by the motion information; Electronic watermark embedding processing apparatus, comprising: an adding unit that executes a process of embedding the digital watermark pattern in the image signal.

Further, in one embodiment of the digital watermark embedding processing apparatus of the present invention, the signal modulating means is such that the image of the motion information is moving with respect to the digital watermark pattern generated by the digital watermark pattern generating means. The digital watermark embedding strength is set to be high when the motion information indicates that the image is not moving, and the digital watermark embedding strength is set to be low when the motion information indicates that the image is not moving. .

Further, in one embodiment of the digital watermark embedding processing apparatus of the present invention, the signal modulating means converts the digital watermark pattern generated by the digital watermark pattern generating means into an image based on the motion information. The watermark embedding strength is gradually increased in the plurality of frames near the boundary where the image transitions from the still frame to the moving frame, and the watermark embedding strength is increased in the plurality of frames near the boundary where the image moves from the moving frame to the still frame. Is characterized in that the modulation processing is performed to set the value to gradually decrease.

Further, in one embodiment of the digital watermark embedding processing apparatus of the present invention, the signal modulating means includes intensity setting means for setting an embedding strength of the digital watermark pattern based on a speed corresponding value indicated by the motion information. Modulation processing means for executing a modulation process for setting the digital watermark embedding strength based on the embedding strength set by the strength setting means.

Further, in one embodiment of the digital watermark embedding processing apparatus of the present invention, the motion detecting means reads an image signal for each frame, calculates a correlation between a plurality of temporally continuous image frame data, and calculates a correlation. Correlation calculation means for outputting information, and a motion determination means for calculating a motion vector based on the correlation information output from the correlation calculation means, and outputting motion information V based on the calculated motion vector, The signal modulation unit is configured to execute a modulation process based on the motion information V on the digital watermark pattern generated by the digital watermark pattern generation unit.

Further, in one embodiment of the digital watermark embedding processing apparatus of the present invention, the motion detecting means reads an image signal for each frame, and calculates a correlation between a plurality of temporally continuous image frame data in the frame. Correlation calculation means for outputting correlation information based on a matching value calculated as the sum of absolute values of the differences between the luminance values of the corresponding pixels, and based on the correlation information output by the correlation calculation means,
A motion determining unit that calculates a motion vector having a minimum matching value and outputs motion information V based on the calculated motion vector, wherein the signal modulating unit includes an electronic watermark generated by the digital watermark pattern generating unit. The modulation pattern based on the motion information V is executed on the watermark pattern.

Further, in one embodiment of the digital watermark embedding processing apparatus of the present invention, the signal modulating means converts the digital watermark pattern generated by the digital watermark pattern generating means into a speed corresponding value indicated by the motion information. Accordingly, a modulation process for setting a follow-up amount of the digital watermark is performed so as to indicate a motion following the motion indicated by the motion vector.

Further, a second aspect of the present invention is a digital watermark embedding method for executing a digital watermark embedding process on an image signal, and a digital watermark pattern generating step of generating a digital watermark pattern based on the embedded information. A motion detection step of obtaining a motion vector based on an image signal to be subjected to a digital watermark pattern embedding process, and outputting motion information based on the motion vector;
The digital watermark pattern generated in the digital watermark pattern generating step is subjected to a signal modulation step of performing a modulation process for changing an embedding strength in accordance with a speed corresponding value indicated by the motion information, and is modulated in the signal modulation step. And an adding step of executing a process of embedding the digital watermark pattern in the image signal.

Further, in one embodiment of the digital watermark embedding processing method of the present invention, the signal modulating step includes:
When the motion information indicates that the image is moving with respect to the digital watermark pattern generated in the digital watermark pattern generating step, the digital watermark embedding strength is increased, and the motion information indicates that the image is not moving. In this case, a modulation process of setting the digital watermark embedding strength to be small is performed.

Further, in one embodiment of the digital watermark embedding processing method of the present invention, the signal modulating step includes:
With respect to the digital watermark pattern generated in the digital watermark pattern generating step, the digital watermark embedding strength is gradually increased in a plurality of frames near the boundary where the image transitions from a still frame to a moving frame based on the motion information. In a plurality of frames near the boundary where the image moves from a moving frame to a stationary frame, a modulation process is performed in which the digital watermark embedding strength is set to gradually decrease.

Further, in one embodiment of the digital watermark embedding processing method of the present invention, the signal modulating step includes:
An intensity setting step for setting the embedding strength of the digital watermark pattern based on the speed corresponding value indicated by the motion information, and a modulation process for setting the digital watermark embedding strength based on the embedding strength set in the strength setting step are executed. And performing a modulation processing step.

Further, in one embodiment of the digital watermark embedding processing method of the present invention, the motion detecting step includes:
An image signal is read for each frame, a correlation calculation step of calculating a correlation between a plurality of temporally continuous image frame data and outputting correlation information, and calculating a motion vector based on the correlation information output in the correlation calculation step And a motion determining step of outputting motion information V based on the calculated motion vector, wherein the signal modulating step performs the motion information processing on the digital watermark pattern generated in the digital watermark pattern generating step. A modulation process based on V is performed.

Further, in one embodiment of the digital watermark embedding processing method of the present invention, the motion detecting step includes:
An image signal is read for each frame, and correlation information is output based on a matching value that calculates a correlation between a plurality of temporally continuous image frame data as a sum of absolute values of differences between luminance values of corresponding pixels in the frame. And a motion determining step of calculating a motion vector having a minimum matching value based on the correlation information output in the correlation calculating step, and outputting motion information V based on the calculated motion vector. Wherein the signal modulating step performs a modulation process based on the motion information V on the digital watermark pattern generated in the digital watermark pattern generating step.

Further, in one embodiment of the digital watermark embedding processing method of the present invention, the signal modulating step includes:
For the digital watermark pattern generated in the digital watermark pattern generating step, a follow-up amount of the digital watermark is set so as to indicate a motion following the motion indicated by the motion vector according to the speed corresponding value indicated by the motion information. And performing a modulation process.

Further, a third aspect of the present invention is a program for causing a computer system to execute a process of embedding a digital watermark in an image signal, wherein the digital watermark pattern generation process generates a digital watermark pattern based on embedded information. A motion detecting step of obtaining a motion vector based on an image signal to be subjected to digital watermark pattern embedding processing, and outputting motion information based on the motion vector; and a digital watermark pattern generated in the digital watermark pattern generating step. A signal modulation step of executing a modulation process for changing an embedding strength in accordance with a speed corresponding value indicated by the motion information; and embedding a digital watermark pattern modulated in the signal modulation step into the image signal. And an adding step of performing a process. In program characterized and.

The program of the present invention is provided in a computer-readable format to a general-purpose computer system capable of executing various program codes, for example, a storage medium such as a CD, an FD, and an MO. The program of the present invention can be stored in a medium that provides a computer program in a computer-readable format for a general-purpose computer system that can execute various program codes, for example. is there. The form of the medium is not particularly limited, such as a recording medium such as a CD, an FD, and an MO, and a transmission medium such as a network.

Such a program regulates the execution of various functions of the system based on the reading of the program under the control of the processor, and exerts a cooperative action on the system. The same operation and effect as those of the aspect can be obtained.

Still other objects, features and advantages of the present invention are:
It will become apparent from the following more detailed description based on the embodiments of the present invention and the accompanying drawings.

[0069]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a digital watermark embedding processing apparatus and a digital watermark embedding processing method according to the present invention will be described in detail with reference to the drawings.

[Configuration Example 1 of Digital Watermark Embedding Processing Apparatus]
FIG. 3 is a block diagram showing the digital watermark embedding processing device 100 according to one embodiment of the present invention. In the digital watermark embedding processing device 100, the PN generation unit 121
(Pseudorandom Noise; pseudo-noise code) sequence random number data PN is generated, and a digital watermark is embedded using this as a basic pattern. The subsequent multiplying unit 122 spectrum-spreads the digital watermark embedding information DC using the random number data PN, and spreads the spread digital watermark information DC with the digital watermark pattern WM1.
And By spreading the embedded information DC in a spectrum using the random number data PN, a digital watermark pattern WM1 that is difficult to analyze can be generated. In the configuration of FIG. 3, the PN generation unit 121 and the multiplication unit 122 configure a first digital watermark pattern generation unit for generating the digital watermark pattern WM1.

The digital watermark embedding information DC is, for example, "copy free (Copy Free)", "copy once (Copy Once)", "absolute copy prohibition (copy once)" as copy control information in accordance with the digital watermark embedding target signal. N
ever Copy) "and the like.

In the digital watermark embedding processing apparatus 100, the motion detecting section 123 detects the motion of an image with respect to the digital video signal DV1 sequentially inputted, and
Is output. The motion detection processing in the motion detection unit 123 is executed by analyzing an input image by an image analysis method in consideration of human visual characteristics.

Digital watermark embedding processing device 10 of the present invention
0 indicates that, based on the motion information detected by the motion detection unit 123, the process of stopping the digital watermark pattern when the image is stationary and moving the digital watermark pattern following the image when the image is moving is performed. With this configuration, a digital watermark is embedded so that it is difficult for human eyes to perceive. This makes it possible to effectively suppress the influence of the digital watermark on the image quality without changing the overall embedding strength.

FIG. 4 shows a digital watermark embedding processing apparatus 10.
FIG. 4 is a block diagram illustrating a detailed configuration of a motion detection unit 123 during the period 0. In the motion detection unit 123, the signal storage unit 126 stores the digital video signal DV1 sequentially input for each frame, and outputs a delayed digital video signal DV1 'delayed by one frame. Here, using the fact that two temporally continuous image signals have pixel values with high correlation,
The motion detection of the image signal is performed by determining the motion vector that maximizes the frame correlation in the optimally set search range.

The subsequent correlation calculator 127 calculates a frame correlation between the delayed digital video signal DV1 'output from the signal storage unit 126 and the input digital video signal DV1, and outputs correlation information M. Here, in two digital video signals DV1 ′ and DV1 that are temporally continuous,
For example, the absolute value of the difference between the luminance values between the corresponding pixels is calculated, and the matching value summed in the frame is used as an index of the frame correlation. That is, the matching value in the motion vector search range (Vx, Vy) is a value represented by the following equation.

[0076]

M (Vx, Vy) = Σ | DV1 ′ (x, y)
−DV1 (x + Vx, y + Vy) |

Next, the search range of the motion vector is changed, and
The calculation of [Equation 12] is repeated, and all matching values for each motion vector are calculated. As a result, a frame correlation plane in the motion vector search range (Vx, Vy) is obtained.

The subsequent motion judging unit 128 determines a motion vector (Vx, Vy) at which the frame correlation becomes maximum based on the correlation information M output from the correlation calculating unit 127, and outputs the motion information V. That is, in the frame correlation plane obtained by the correlation calculation unit 127, the motion vector (V
x, Vy) as motion information V. The motion information is represented by the following equation.

[0079]

V (x, y) = arg min M (Vx,
Vy)

At this time, the delayed digital video signal DV1 '
Indicates that the input digital video signal DV1 is moved by the motion vector (Vx, Vy) and changes with time. In this way, by determining a motion vector that maximizes the frame correlation between two temporally continuous image signals in the optimally set search range, the motion information of the image signal can be detected.

Returning to FIG. 3, description of the digital watermark embedding processing device will be continued. The signal modulating section 124 includes the motion detecting section 12
3 receives the motion information V output, modulates the digital watermark pattern WM1 based on the motion information V, and outputs the digital watermark pattern WM2 in consideration of human visual characteristics to the adding unit 125.

When the input digital video signal DV1 is stationary, the signal modulating section 124
Generates a digital watermark pattern WM2 by modulating the digital watermark pattern WM1 as a stationary pattern in accordance with the motion information V = (0, 0) output by the input digital video signal DV1 and the input digital video signal DV1 by the motion vector (Vx, Vy). When moving, the motion information V =
A digital watermark pattern WM2 is generated by a modulation process in which a process of moving the digital watermark pattern WM1 following an image according to (Vx, Vy) is generated and output to the adding unit 125. That is, the signal modulation unit 124 executes the digital watermark pattern modulation process based on the motion information V output as a value corresponding to the moving speed and the direction of the image so as to indicate the motion following the motion indicated by the motion vector. . With this processing, a still digital watermark pattern can be embedded in a still image, and a digital watermark pattern following a motion can be embedded in a moving image, so that a digital watermark can be embedded so that it is difficult for human eyes to perceive. This makes it possible to effectively suppress the influence of the digital watermark on the image quality without changing the overall embedding strength.

According to the motion information V output from the motion detecting unit 123, the signal modulating unit 124 sets the digital watermark pattern WM1
The addition unit 125 that inputs the digital watermark pattern WM2 generated by performing the modulation processing of (1) adds the digital watermark pattern WM2 output from the signal modulation unit 124 to the input digital video signal DV1, thereby obtaining the input digital video signal DV1. And outputs a digital video signal DV2 in which the digital watermark information DC is embedded in the same format as the above.

The output digital video signal DV2 is encoded by a predetermined encoder and transmitted from a broadcasting station or the like via a medium such as a satellite wave, a terrestrial wave, or a cable. Encode by the encoder and expose the master disc,
The disc is provided by an optical disc from the master disc.

As described above, the digital watermark embedding processing apparatus of the present invention shown in FIG. 3 acquires the motion information of the image to be subjected to the digital watermark embedding process, and executes the modulation process of the digital watermark pattern according to the motion information. For still images, a still digital watermark pattern is added to the input image, and for moving images, a digital watermark pattern is embedded that follows the movement. You can embed a watermark. This makes it possible to effectively suppress the influence of the digital watermark on the image quality without changing the overall embedding strength.

[Digital Watermark Embedding Processing Flow]
The processing procedure in the digital watermark embedding processing apparatus of the present invention will be described with reference to the flow shown in FIG. FIG.
Is a processing procedure of a digital watermark embedding processing apparatus that performs motion detection on an input signal such as a digital video signal, modulates a digital watermark pattern in accordance with motion information, and embeds the input signal. It is a flowchart which shows. Each step will be described.

First, in step S11, the digital watermark embedding processing device generates random number data of a PN sequence,
In step S12, according to the digital watermark embedding target signal, “copy permitted (Copy Free)”, “copy permitted once (Copy Once)”, “absolute copy prohibited (N
embedded copy, such as copy control information, is spectrum-spread with random number data PN to generate a digital watermark pattern WM1.

Subsequently, in step S13, the digital watermark embedding processing device inputs the input digital video signal DV1.
Are read sequentially for each frame data, and in step S14, the input digital video signal DV
The image correlation is calculated for 1 and the correlation information M is output.
Subsequently, in step S15, the digital watermark embedding processing device performs image motion detection based on the correlation information M,
The motion information V is output. That is, the input digital video signal DV1 is stored for each frame to generate a delayed digital video signal DV1 'delayed by one frame, and based on the two temporally continuous digital video signals DV1' and DV1, the aforementioned [ Equation 12 is applied to calculate a frame correlation plane in the motion vector search range (Vx, Vy), and then Equation 13 is applied to determine the motion vector (Vx, Vy) that gives the maximum correlation. Are output as motion information V.

Subsequently, in step S16, the digital watermark embedding processing device modulates the digital watermark pattern WM1 based on the motion information V, and outputs a digital watermark pattern WM2 in consideration of human visual characteristics. That is, based on the detected motion information V, the input digital video signal D
If V1 is stationary, the digital watermark pattern WM1
When the input digital video signal DV1 is moving, the digital watermark pattern WM1 is also moved and the digital watermark pattern WM2 is generated and output.

The digital watermark pattern WM2 that has been subjected to such a modulation processing is used when the input image is stationary.
When the input image is stationary and there is a movement, the input image moves in accordance with the movement of the image, which makes it difficult for human eyes to perceive. As a result, without changing the overall embedding strength,
The effect of the digital watermark on the image quality can be effectively suppressed.

Subsequently, the digital watermark embedding processing apparatus proceeds to step S17, adds the modulated digital watermark pattern WM2 to the input signal, and in step S18, adds the digital watermark information in the same format as the input signal. Is output.

Subsequently, in step S19, the digital watermark embedding processing device determines whether or not processing of the input signal has been completed. If a negative result is obtained here, step S13 is performed.
And the following processing is repeatedly executed. The digital watermark embedding processing device sequentially processes the input signal by repeatedly performing the same process, and completes the process when a positive result is obtained in the determination of the end of the input in step S19.

A specific example of the motion detection processing in the above-described digital watermark embedding processing apparatus will be described with reference to FIG. FIG.
Shows an example in which the image signal is shifted in the horizontal direction. Human visual characteristics tend to follow a moving object, and when a digital watermark pattern is superimposed on an image signal with some movement, there is a stationary digital watermark pattern on the background of a moving picture Then, the digital watermark pattern is easily perceived, and the image quality is greatly deteriorated. Therefore, as described above, the digital watermark pattern is moved in the same manner as the moving picture.

When there are image frames as shown in FIG. 6A and FIG. 6B as temporally continuous image signals, for example, the above-mentioned matching value calculation formula [Equation 12] is applied to these image frames. Is applied to calculate a matching value, and further, a motion vector is calculated by applying a motion vector calculation formula [Equation 13].

In this example, a motion vector (Vx, 0) in the horizontal (X) direction as shown in FIG. 6C is calculated. In this case, the detected motion information V = (Vx, 0)
The digital watermark pattern shown in FIG. 6D is moved by the horizontal motion vector (Vx, 0) in accordance with the above and modulated into the digital watermark pattern FIG. Can be followed.

Based on motion information detected from temporally continuous image signals by this method, the digital watermark pattern is also stopped when the image signal is stationary, and the digital watermark pattern is stopped when the image signal is moving. By moving the watermark pattern so as to follow the motion information, it becomes possible to embed an electronic watermark in such a manner that the watermark is hardly perceived by human eyes.

The process of modulating the digital watermark pattern so as to show the same motion in accordance with the motion of the image is one of the methods for making the digital watermark less perceptible to human eyes. Alternatively, moving information is detected by acquiring the above-described motion vector, and based on the motion vector, when it is determined that the image signal is stationary, the electronic watermark pattern is also stopped, and it is determined that the image signal is moving. In this case, the digital watermark embedding process may be performed by executing a modulation process for randomly moving the digital watermark pattern. Even with this configuration, it is possible to embed a digital watermark that is hardly perceived by human eyes. In this case, the motion vector of the image signal and the motion vector of the digital watermark pattern are different, but it is difficult to perceive the digital watermark pattern moving at random on the background of the moving picture, so that the effect on the image quality can be suppressed. it can.

[Digital Watermark Embedding Processing Apparatus Configuration Example 2]
The above-described digital watermark embedding processing device also stops the digital watermark pattern when the image signal is stationary based on the motion information detected from the image signal using the frame correlation of the image signal, and In the case of a moving apparatus, the processing apparatus has a configuration in which the digital watermark pattern is also moved following or moved at random. Next, based on the motion information detected from the image signal, by performing modulation processing of various digital watermark patterns different from the above device,
A configuration for performing embedding of a digital watermark that is difficult for human eyes to detect will be described.

FIG. 7 is a diagram for explaining the amount of movement of a temporally continuous image signal and the amount of movement of a digital watermark pattern that follows the amount of movement. Here, the motion amount of the image signal is obtained by calculating a matching value based on the above [Equation 12].
It means the magnitude of the motion vector obtained from the obtained matching value based on [Equation 13]. Based on a motion vector detected from a temporally continuous image signal, that is, based on motion information, the digital watermark pattern is also stopped when the image signal is stationary, and the digital watermark pattern when the image signal is moving. In the case where the moving amount is also followed, the moving amount of the image signal and the following amount of the digital watermark pattern are superimposed on the image signal by controlling the digital watermark pattern so as to have a proportional relationship as shown in FIG. do it. This corresponds to the processing described in the above-mentioned [Digital watermark embedding processing device 1].

Here, for example, a case is considered in which a still digital watermark pattern is superimposed on an image signal moving at various speeds. When observing an image in which a stationary digital watermark pattern is embedded for a picture moving at various speeds as described above, the human visual characteristic is the speed of movement of the image signal, that is, temporally continuous. It depends on the magnitude of the motion vector detected from the image signal.

If the image signal is stationary or the movement of the image signal is extremely small, the image signal and the digital watermark pattern are perceived as stationary by the human eye, so that deterioration of the image quality is hardly perceived. Become. On the other hand, when the movement of the image signal is extremely large, the human eye follows the movement of the image signal. Also in this case, since the stationary digital watermark pattern cannot be detected by human eyes, it is difficult to perceive the deterioration of the image quality due to the digital watermark.

As described above, whether the image signal is stationary,
Alternatively, when the motion of the image signal is extremely small, or when the motion of the image signal is extremely large, the digital watermark pattern is hard to be perceived by human eyes even if a stationary digital watermark pattern is embedded, and the image quality is deteriorated due to the digital watermark. Is difficult to perceive. However, when the movement of the image signal is approximately between these levels, a state occurs in which the human eye easily follows the movement of the image signal but easily senses the stationary digital watermark pattern. In such a case, while observing a slowly moving image, a still digital watermark is also caught in the eyes, and deterioration of image quality due to the digital watermark is easily perceived.

A configuration in which the processing for embedding the digital watermark pattern in a manner that is most difficult for human eyes to follow in accordance with the movement of the image signal will be described below.

In the digital watermark embedding processing apparatus of this configuration, a matching value is obtained based on motion information detected from a temporally continuous image signal, specifically, the above-mentioned [Equation 12], and the obtained matching value is obtained. If the motion of the image signal is still, small, or extremely large based on the magnitude of the motion vector obtained based on [Equation 13], the embedding of a still digital watermark pattern is executed, and If the magnitude of the vector indicates an intermediate speed, embedding of a digital watermark pattern having the same motion as the motion vector is executed.

According to this configuration, it is only necessary to execute a process of following and moving the digital watermark pattern only when the image signal is moving at such a speed that the human eye can detect the stationary digital watermark pattern. The amount of calculation required to execute the pattern movement processing can be reduced.
When the motion of the image signal is stationary, small, or extremely large, the embedding of the stationary digital watermark pattern is executed, and the occurrence rate of the displacement of the digital watermark pattern due to the movement of the digital watermark pattern is reduced. Therefore, it is possible to prevent the detection accuracy of the digital watermark information from being lowered.

FIG. 7B is a diagram for explaining the amount of motion of an image signal and the amount of motion of a digital watermark pattern that follows the amount of motion in the digital watermark embedding processing apparatus of this embodiment.

As shown in FIG. 7 (b), when the image signal is stationary or when the amount of movement of the image signal is extremely small, and further when the amount of movement of the image signal is extremely large, human visual perception may occur. Since the stationary digital watermark pattern cannot be perceived, the digital watermark pattern is controlled to be stationary and is superimposed on the image signal. In addition, when the motion amount of the image signal is in the middle of these ranges, since a still digital watermark pattern can be perceived by human eyes, the motion amount of the image signal and the follow-up amount of the digital watermark pattern are different. For example, the digital watermark pattern is controlled so as to be in a proportional relationship, and is superimposed on the image signal. This makes it possible to efficiently modulate the digital watermark pattern in consideration of human visual characteristics and superimpose the digital watermark pattern so as to follow the movement of the image signal.

As described above, when the image signal is stationary or the motion amount is extremely small, or when the motion amount is extremely large, the digital watermark pattern is stopped and superimposed on the image signal, and the motion amount of the image signal is reduced. Regarding the configuration of a digital watermark embedding processing device that executes processing for controlling a digital watermark pattern and superimposing it on an image signal so that the amount of movement of the image signal and the amount of follow-up of the digital watermark pattern are in a proportional relationship, for example, in the case of an intermediate level This will be described below.

Also in the digital watermark embedding processing apparatus of this embodiment, the amount of motion of the image signal is obtained by calculating a matching value based on the above-mentioned [Equation 12] and calculating the matching value from the obtained matching value.
A configuration obtained based on the magnitude of the motion vector obtained based on [Equation 13] is applicable. Therefore, the basic configuration is the same as that of the digital watermark embedding processing apparatus 100 of FIG. The digital watermark embedding processing device of the present embodiment is realized by changing the configuration of the signal modulation unit 124 of the digital watermark embedding processing device 100 of FIG.

FIG. 8 is a block diagram showing the configuration of the signal modulating section 124 of the digital watermark embedding processing device of this embodiment. The signal modulation unit 124 receives the motion information V from the motion detection unit 123, receives the digital watermark pattern WM1 from the multiplication unit 122, executes a modulation process on the digital watermark pattern WM1, and adds the digital watermark pattern WM2 to the addition unit 125.
Output to Here, the motion information V is the motion detection unit 123
Corresponds to a motion vector calculated based on [Expression 13] from the above-described [Expression 13], and a matching value is calculated based on [Expression 12].

The follow-up amount setting section 131 of the signal modulation section 124
Receives the motion information V from the motion detection unit 123 and determines the follow-up amount of the embedded digital watermark pattern based on the motion information V. The follow-up amount setting unit 131 converts the amount of movement of the image signal shown in FIG. 7B and the amount of movement of the digital watermark pattern to be followed, or the amount of movement of the image signal, that is, the movement information V It has an arithmetic function of outputting the follow-up amount information F (V) of the digital watermark pattern as an input.

That is, the following amount setting section 131 sets the magnitude | F (V) | of the electronic watermark pattern according to the motion information V from the motion detecting section 123, that is, the magnitude | V | of the motion vector. Modulation processing unit 1 by setting as follows
32.

[0113]

## EQU14 ## 0 ≦ | V | <a → | F (V) | = 0 a ≦ | V | <b → | F (V) | = a to b (| F (V) |
= V) b <| V | → | F (V) | = 0

In the above equation, a, b, are values set corresponding to the magnitude (velocity value) of the motion vector.
0 <a <b. The follow-up amount setting unit 131 sets the follow-up amount information F (V) of the digital watermark pattern according to the motion information V from the motion detection unit 123 as described above, and outputs the same to the modulation processing unit 132. The modulation processing unit 132 modulates the digital watermark pattern WM1 according to the following amount information F (V), and outputs the digital watermark pattern WM2 to the adding unit 126.

For example, when the magnitude (velocity value) of the motion vector input from the motion detection unit 123 is 0 ≦ | V | <a,
Alternatively, when b <| V |, the following amount setting unit 131
Is | F (V) | = 0, that is, F (V) = (0,
0) to the modulation processing unit 132,
Generates a digital watermark pattern WM2 by executing a modulation process in which the digital watermark pattern WM1 is also stopped according to the following amount information F (V) = (0, 0).

On the other hand, if the magnitude (velocity value) of the motion vector input from the motion detecting section 123 satisfies a ≦ | V | <b, the following amount setting section 131 sets | F (V) | = a ~
b = V, that is, a modulation process for moving the digital watermark pattern WM1 following the image according to F (V) = V (Vx, Vy) similar to the motion vector V input from the motion detection unit 123. To generate a digital watermark pattern WM2 and output it to the adding unit 125.

By this processing, when the image signal is stationary or the amount of motion is extremely small, or when the amount of motion is extremely large, the digital watermark pattern is stopped and superimposed on the image signal, and the amount of motion of the image signal is reduced. In the case of an intermediate level, it is possible to control the digital watermark pattern so that the amount of movement of the image signal and the follow-up amount of the digital watermark pattern are in a proportional relationship, and to embed the digital watermark pattern in the image signal. The digital watermark can be embedded as follows.

[Digital Watermark Embedding Processing Flow]
When the above-described image signal is stationary or the amount of motion is extremely small, or when the amount of motion is extremely large, the digital watermark pattern is stopped and superimposed on the image signal, and the amount of motion of the image signal is approximately intermediate between these. FIG. 9 shows a processing procedure of a digital watermark embedding processing device that executes a process of controlling a digital watermark pattern and embedding it in an image signal so that the motion amount of the image signal and the follow-up amount of the digital watermark pattern have a proportional relationship. This will be described with reference to the flow. FIG.
Is a processing procedure of a digital watermark embedding processing apparatus that performs motion detection on an input signal such as a digital video signal, modulates a digital watermark pattern in accordance with motion information, and embeds the input signal. It is a flowchart which shows. Each step will be described.

First, in step S21, the digital watermark embedding processing apparatus generates random number data of a PN sequence.
In step S22, according to the digital watermark embedding target signal, “copy permitted (Copy Free)”, “copy permitted once (Copy Once)”, “absolute copy prohibited (N
embedded copy, such as copy control information, is spectrum-spread with random number data PN to generate a digital watermark pattern WM1.

Subsequently, in step S23, the digital watermark embedding processing device inputs the input digital video signal DV1.
Are sequentially read for each frame data, and in step S24, the image correlation is calculated for the temporally continuous input digital video signal, and the correlation information M is output. Subsequently, in step S25, the digital watermark embedding processing device performs image motion detection based on the correlation information M, and outputs motion information V.

For example, the digital video signal DV1 is stored for each frame to generate a delayed digital video signal DV1 'which is delayed by one frame, and in the two digital video signals DV1' and DV1 which are temporally continuous, the above-mentioned [ Based on Equation 12, the motion vector search range (V
x, Vy), and calculates a motion vector (Vx, Vy) that gives the maximum correlation based on [Equation 13].
Is determined, and the motion information V is output.

Subsequently, the digital watermark embedding processing device determines a follow-up amount based on the motion information V in step S26. That is, when the magnitude of the input motion vector is 0 ≦ | V | <a or b <| V |, a tracking amount is set as | F (V) | = 0, The magnitude (velocity value) of the motion vector is a ≦ | V | <b
, The following amount is set to | F (V) | = ab = V.

Subsequently, in step S27, the digital watermark embedding processing device modulates the digital watermark pattern WM1 based on the following amount information F (V), and outputs a digital watermark pattern WM2 in consideration of human visual characteristics. That is, for example, the modulation processing unit 132 outputs the following amount information F (V).
= (0,0), the digital watermark pattern W
If M1 is also subjected to a modulation process as a stationary pattern, a digital watermark pattern WM2 is generated, and if non-zero following amount information F (V) = V (Vx, Vy) is input, following amount information is obtained. In accordance with F (V) = V (Vx, Vy), a digital watermark pattern WM2 is generated by performing a modulation process of moving the digital watermark pattern WM1 so as to follow the image, and is output to the adding unit 125.

That is, the follow-up amount of the digital watermark pattern is determined on the basis of the detected motion information V. When the input digital video signal DV1 is stationary or has a very small amount of motion, and when the amount of motion is extremely large, When the digital watermark pattern is stopped, and the amount of motion of the image signal is about the middle of these values, the digital watermark pattern is modulated by executing a modulation process in which the amount of follow-up of the digital watermark pattern is set so as to move in accordance with the amount of motion of the image signal. A watermark pattern WM2 is generated.

Subsequently, in step S28, the digital watermark embedding processing device adds the modulated digital watermark pattern WM2 to the input signal, and in step S29, adds the signal in which the digital watermark information is embedded in the same format as the input signal. Output.

Subsequently, in step S30, the digital watermark embedding processing device determines whether or not the processing of the input signal has been completed, and if a negative result is obtained here, step S23.
And the following processing is repeatedly executed. The digital watermark embedding processing device sequentially processes the input signal by repeatedly performing the same processing on the input signal. When a positive result is obtained in the determination of the end of the input in step S30, the process is completed.

The configuration of the present embodiment is a configuration in which a motion vector is calculated from an input image, and the follow-up amount of a digital watermark is set based on the calculated motion vector. Modulation of a digital watermark pattern that achieves tracking can be performed, and embedding of a digital watermark that is not visually noticeable can be performed.

[Digital Watermark Embedding Processing Apparatus Configuration Example 3]
Next, a configuration will be described in which processing for changing the embedding strength of a digital watermark is executed based on motion information detected from an image signal, and embedding of a digital watermark that is difficult for human eyes to detect is performed.

FIG. 10 is a diagram for explaining the process of adjusting the embedding strength when a digital watermark pattern is superimposed on a temporally continuous image signal. Here, the embedding strength is a value corresponding to the non-negative scalar amount C shown in the above [Equation 10]. As described above, in order to improve the reliability of digital watermark detection, a process of increasing the embedding strength of the digital watermark using the non-negative scalar amount C is executed. The frame data DV2 of the luminance signal when the digital watermark is embedded by increasing the embedding strength of the digital watermark using the scalar amount C is represented by DV2 = DV1 + CWM.

On the basis of the motion information detected from the temporally continuous image signal, for example, there is no motion from frame 0 to frame n, there is motion from frame n to frame m, and there is no motion from frame m to frame m. Consider an image signal that changes over time. Here, the motion of the image signal is obtained by calculating a matching value based on the above [Equation 12].
It is obtained based on the magnitude of the motion vector obtained based on [Equation 13] from the obtained matching value.

When the digital watermark strength is not changed,
As shown in FIG. 10A, a digital watermark pattern is superimposed on each of frames 0 to n to m with a constant embedding strength. In order to improve the reliability of digital watermark detection, it is desirable to embed a digital watermark with higher strength. However, there is a problem that a digital watermark with high strength is easily noticeable to human eyes and causes deterioration in image quality. Also,
When there is motion in the image, the digital watermark tends to be difficult to recognize, and when the image is stationary, the digital watermark tends to be easy to recognize. Therefore, the digital watermark embedding processing apparatus according to the present embodiment increases the digital watermark embedding strength when an image moves, and reduces the digital watermark embedding strength when the image does not move. And

For example, as shown in FIG. 10B, the embedding strength in a moving frame is set to be larger than the embedding strength in a non-moving frame, and a digital watermark pattern is superimposed. At this time, it is preferable to perform a process of making the digital watermark pattern follow the movement of the image signal. With this configuration, it is difficult for human eyes to perceive, and it is possible to improve the reliability of detection in digital watermark detection processing.

In addition, abruptly changing the strength of the digital watermark between a frame having no image movement and a frame having the image movement may cause a change in the strength of the digital watermark pattern to be easily perceived at a frame boundary. There is. That is, for example, in an image signal that changes from a moving frame to a non-moving frame, the strength and the movement of the digital watermark pattern superimposed so as to follow the movement of the image signal at the moment when the movement of the image signal stops. It may change rapidly, and the change (deterioration) in image quality may increase.

In such a case, for example, FIG.
As shown in the figure, by performing processing for smoothly changing the embedding strength of the digital watermark pattern at the boundary between the moving frame and the non-moving frame, the embedding strength of the digital watermark pattern at the frame boundary is changed. Deterioration of image quality can be effectively suppressed.

The configuration of a digital watermark embedding processing apparatus that realizes a process of embedding a digital watermark pattern in a manner most unlikely to be noticed by the human eye in accordance with the transition of motion between frames of an image signal will be described below. In the digital watermark embedding processing device of this configuration, a matching value is obtained based on motion information detected from a temporally continuous image signal, specifically, the above-mentioned [Equation 12]. [13], the motion information of the image signal is obtained based on the magnitude of the motion vector obtained based on [13], and embedding of a digital watermark pattern whose strength is adjusted based on the motion information is executed. Therefore, the basic configuration is the same as that of the digital watermark embedding processing apparatus 100 of FIG. The digital watermark embedding processing device of the present embodiment is realized by changing the configuration of the signal modulation unit 124 of the digital watermark embedding processing device 100 of FIG.

FIG. 11 is a block diagram showing the configuration of the signal modulating section 124 of the digital watermark embedding processing apparatus of the present embodiment. The signal modulator 124 receives the motion information V from the motion detector 123, receives the digital watermark pattern WM1 from the multiplier 122, executes a modulation process on the digital watermark pattern WM1, and adds the digital watermark pattern WM2 to the adder 12
5 is output. Here, the motion information V is stored in the motion detection unit 12.
3 obtains a matching value based on the above [Equation 12],
This corresponds to a motion vector obtained from the obtained matching value based on [Equation 13].

The intensity setting unit 141 of the signal modulation unit 124
Upon receiving the motion information V from the motion detection unit 123,
The embedding strength of the embedding digital watermark pattern is determined based on The strength setting unit 141 determines the correspondence between the amount of motion of the image signal shown in FIG. 10B or FIG. 10C and the embedding strength C of the digital watermark pattern, or the amount of motion of the image signal, that is, the motion information. It has a calculation function of outputting the embedding strength C of the digital watermark pattern with V as an input.

That is, the intensity setting unit 141 sets the digital watermark pattern intensity C in accordance with the motion information V from the motion detection unit 123, that is, the magnitude | V | 142.

[0139]

| V | = 0 → C = C1 | V | ≠ 0 → C = C2

In the above equation, C1 and C2 are digital watermark embedding strength scalar values set corresponding to the magnitude (velocity value) of the motion vector, and have a relationship of C1 <C2. The strength setting unit 141 sets the embedding strength C of the digital watermark pattern according to the motion information V from the motion detection unit 123 as described above, and outputs it to the modulation processing unit 142.
The modulation processing unit 142 controls the digital watermark pattern WM1 according to the embedding strengths C1 and C2 set by the strength setting unit 141.
Is performed and the digital watermark pattern WM2 is added to the adder 1
26.

Note that the modulation processing unit 142
Also, the motion information V, that is, the motion vector input from 23 is input, and the modulation process for following the digital watermark according to the motion of the image is performed similarly to the digital watermark embedding processing device 1 described above.

That is, when the input digital video signal DV1 is stationary, the modulation processing unit 142 also stops the digital watermark pattern WM1 in accordance with the motion information V = (0, 0) output by the motion detecting unit 123. The digital watermark pattern WM2 is generated by performing the intensity modulation based on the scalar amount C1 while performing the modulation as the modulated pattern. Also,
The input digital video signal DV1 is a motion vector (Vx,
Vy), the digital watermark pattern WM1 is moved according to the image according to the motion information V = (Vx, Vy) output from the motion detector 123, and the scalar amount C2 is changed. The digital watermark pattern WM2 is generated by performing intensity modulation based on the digital watermark pattern.

By this processing, it is possible to embed a still digital watermark pattern of a still weak intensity in a still image, and to embed an electronic watermark pattern following a strong motion in a moving image. It is possible to embed a digital watermark.

In the above-described embodiment, the scalar amounts of the intensity setting are two types, C1 and C2. However, according to the amount of motion of the image, C1, C2, C3... Further, the configuration may be such that the intensity setting is further subdivided.

Further, as described with reference to FIG. 10C, a configuration may be employed in which the processing for smoothly changing the embedding strength of the digital watermark pattern at the boundary between a moving frame and a non-moving frame is executed. . That is, the digital watermark embedding strength is gradually increased in a plurality of frames near the boundary where the image shifts from the still frame to the frame where the image moves, and in a plurality of frames near the boundary where the image shifts from the frame where the image moves to the still frame. A modulation process is performed to set the digital watermark embedding strength to gradually decrease. In the case of this configuration, prior to the digital watermark pattern modulation process in the signal modulator 124, the motion detection of the preceding image frame is executed, and the motion vector data of each preceding image frame is stored in the memory. The intensity setting unit 141 outputs the intensity C in each frame to the modulation processing unit 142 based on the accumulated motion information of the preceding image frame.

[Digital Watermark Embedding Processing Flow]
The processing procedure of the digital watermark embedding processing device for executing the above-described intensity modulation processing will be described with reference to the flow shown in FIG. FIG. 12 shows a digital watermark embedding processing device that executes motion detection on an input signal such as a digital video signal, executes intensity modulation of a digital watermark pattern in accordance with motion information, and embeds the input signal. 6 is a flowchart showing the processing procedure of FIG. Each step will be described.

First, in step S31, the digital watermark embedding processing apparatus generates PN sequence random number data.
In step S32, according to the digital watermark embedding target signal, “copy permitted (Copy Free)”, “copy permitted once (Copy Once)”, “absolute copy prohibited (N
embedded copy, such as copy control information, is spectrum-spread with random number data PN to generate a digital watermark pattern WM1.

Subsequently, in step S33, the digital watermark embedding processing apparatus inputs the input digital video signal DV1.
Are sequentially read for each frame data, and in step S34, the image correlation is calculated for the temporally continuous input digital video signal, and the correlation information M is output. Subsequently, in step S35, the digital watermark embedding processing device performs image motion detection based on the correlation information M, and outputs motion information V.

For example, the digital video signal DV1 is stored for each frame to generate a delayed digital video signal DV1 'delayed by one frame. In the two digital video signals DV1' and DV1 which are temporally continuous, the above-mentioned [ Based on Equation 12, the motion vector search range (V
x, Vy), and calculates a motion vector (Vx, Vy) that gives the maximum correlation based on [Equation 13].
Is determined, and the motion information V is output.

Subsequently, the digital watermark embedding processing device determines the digital watermark embedding strength based on the motion information V in step S36. That is, for example, when the magnitude of the input motion vector is 0, C = C
If the magnitude of the input motion vector is not 0, an intensity setting of C = C2 is executed.

Subsequently, in step S37, the digital watermark embedding processing device modulates the digital watermark pattern WM1 based on the intensity and the motion information, and outputs a digital watermark pattern WM2 in consideration of human visual characteristics. That is, the modulation processing unit 132 outputs the signal C1
, The output from the intensity setting unit is C1WM1,
If the number is 2, the intensity modulation of C2WM1 is performed, and a modulation process for stopping or following the digital watermark pattern according to the motion information V output by the motion detection unit 123 is performed to generate the digital watermark pattern WM2. .

Subsequently, in step S38, the digital watermark embedding processing device adds the modulated digital watermark pattern WM2 to the input signal, and in step S39, converts the signal in which the digital watermark information is embedded in the same format as the input signal. Output.

Subsequently, in step S40, the digital watermark embedding processing device determines whether or not processing of the input signal has been completed, and if a negative result is obtained here, step S33.
And the following processing is repeatedly executed. The digital watermark embedding processing device sequentially processes the input signal by repeating the same processing, and completes the process when a positive result is obtained in the determination of the end of the input in step S40.

The configuration of the present embodiment is a configuration in which a motion vector is calculated from an input image, and the embedding strength of a digital watermark is set based on the calculated motion vector. Intensity modulation becomes possible, and embedding of a digital watermark that is not visually noticeable becomes possible.

[Digital Watermark Detection Processing Apparatus] Next, the configuration of the digital watermark detection processing apparatus will be described with reference to FIG. The digital watermark detection processing device 150 shown in FIG.
For example, a digital video signal DV2 obtained by receiving from a broadcasting station or the like via a medium such as a satellite wave, a terrestrial wave, or a cable.
Or embedded digital watermark information DC is detected from a digital video signal DV2 obtained by reproducing an optical disk or the like.

In the digital watermark detection device 150, the PN
The generation unit 151 generates PN sequence random number data PN, and detects a digital watermark using the random number data PN as a basic pattern. At this time, the PN generation unit 151 sets the digital watermark embedding processing device 1
PN generation unit 121 or PN generation unit 141 at 00
By generating the same random number data PN, it is possible to correctly detect the digital watermark information DC embedded with difficulty in analysis using spread spectrum.

In the digital watermark detection device 150, the inner product calculation unit 152 receives the digital video signal DV which is sequentially input.
An inner product value with random number data PN is calculated for 2 and an inner product value S is output. The subsequent comparison / determination unit 153 determines the inner product value S
Is compared with an optimally set threshold to determine the presence / absence of digital watermark information DC and the polarity of embedded digital watermark information DC. That is, the following determination is made based on the non-negative threshold value TH.

[0158]

S ≦ −TH: with digital watermark (polarity 0) | S | <TH: without digital watermark S ≧ TH: with digital watermark (polarity 1)

As described above, embedded digital watermark information DC can be detected from an input signal.

For example, when copying a digital video signal DV2 obtained by receiving from a broadcasting station or the like via a medium such as a satellite wave, a terrestrial wave, a cable, or a digital video signal DV2 obtained by reproducing an optical disk or the like. , So that copying can be restricted based on the digital watermark information DC,
In addition, for sources suspected of being pirated,
It is designed to determine the source of the source.

[Digital Watermark Detection Processing Flow] Next, the processing procedure in the digital watermark detection processing apparatus will be described with reference to FIG.
This will be described with reference to the flow shown in FIG. Each step will be described.

First, in step S51, the digital watermark detection processing device generates PN sequence random number data PN. Subsequently, the digital watermark detection processing device proceeds to step S52.
In step S53, frame data such as the digital video signal DV2 is sequentially read. In step S53, an inner product value of the input frame data and the random number data PN is calculated, and an inner product value S is output.

Subsequently, in step S54, the digital watermark detection processing device sets the calculated inner product value S to the set threshold value (T
H), the presence or absence of the digital watermark information DC and the polarity of the embedded digital watermark information DC are determined. That is, for the non-negative threshold value TH, the digital watermark information DC can be detected from the input signal based on the above-described determination of [Expression 14]. Subsequently, in step S55, the digital watermark detection processing device outputs the digital watermark information DC thus detected.

Subsequently, the digital watermark detection processing device proceeds to step S56, and determines whether or not processing of the input signal is completed. If a negative result is obtained here, the process returns to step S52, and the same process is sequentially performed for each input data. Is repeated to process the input signal. If an affirmative result is obtained in the end determination of the input signal in step S56, the process is completed.

[System Configuration] The series of processes described in the above embodiments can be executed by hardware, software, or a combination of both. When executing processing by software, a program recording a processing sequence is installed in a memory in a data processing device built in dedicated hardware and executed, or a general-purpose computer capable of executing various processing is used. It is possible to install and run the program. When a series of processes is performed by software, a program constituting the software is installed in, for example, a general-purpose computer or a one-chip microcomputer. FIG.
An example of a system configuration of an apparatus that executes at least one of the series of processes described above, specifically, digital watermark embedding and detection is shown.

The system has a CPU (Central Processing).
Unit 202). CPU (Central processing Uni
t) 202 includes various application programs and OS
(Operating System) is actually executed. ROM (Read
-Only-Memory) 203 stores a program to be executed by the CPU 202 or fixed data as operation parameters. RAM (Random Access Memory) 204
It is used as a storage area and a work area for a program executed in the processing of the CPU 202 and parameters that change as appropriate in the program processing. CPU 20
2. The ROM 203, the RAM 204, and the hard disk 205 are connected by a bus 201, and can mutually transfer data. Further, data transfer with various input / output devices connected to the input / output interface 211 is possible.

Keyboard 212 and mouse 213 are CPU
The user is operated by the user to input various commands to 202, is operated by the user when inputting command input data, and is input via the keyboard and mouse controller 214.

A drive 209 is a floppy (registered trademark) disk, a CD-ROM (Compact Disc Read Only).
Memory), MO (Magneto optical) disk, DVD (Dig
It is a drive that performs recording and reproduction of a removable recording medium 210 such as an ital Versatile Disc, a magnetic disk, and a semiconductor memory, and reproduces a program or data from each removable recording medium 210 and the removable recording medium 2.
Execute the program or data storage for 10.

The CPU 202 has an input / output interface 2
When a command is input via the keyboard 212, the mouse 213, or the like, via the ROM 10, the ROM (R)
eadOnly Memory) 203 is executed.

In the above-described embodiment, a signal of an image or the like to be embedded with a digital watermark or a signal to be detected is input to another input device such as a camera 2071 connected to the input unit 207, for example, a data input device such as a scanner. Alternatively, a floppy disk or CD connected to the drive 209
-ROM (Compact Disc Read Only Memory), MO (Magn
eto optical) Disc, DVD (Digital Versatile Dis)
c), can be input from a removable recording medium 210 such as a magnetic disk or a semiconductor memory. Audio data can be input via the microphone 2072. Furthermore, it is also possible to process data received via the communication unit 208 as data to be embedded with a digital watermark or data to be detected.

The CPU 202 is not limited to the ROM storage program, but may be a program stored in the hard disk 205, a program transferred from a satellite or a network, received by the communication unit 208 and installed in the hard disk 205, or mounted on the drive 209. The program read from the removable recording medium 210 and installed on the hard disk 205 is
It can also be loaded into an AM (Random Access Memory) 204 and executed.

In the system having the configuration shown in FIG. 15, the CPU 202 performs the processing according to each of the above-described embodiments or the processing performed according to the above-described block diagrams and flowcharts. Then, the CPU 202 transmits the processing result to an LCD (Liquid Crystal Display) through the input / output interface 211 as necessary, for example.
y), display device 2061 such as CRT, speaker 2062
Is output via the output unit 206. Further, the processing data can be transmitted from the communication unit 208 and further stored in a recording medium such as the hard disk 205.

The execution programs for various processes are stored in a hard disk 205 as a recording medium built in the system.
Or in the ROM 203 in advance. Alternatively, the program is a floppy disk, CD-ROM
(Compact Disc Read Only Memory), MO (Magneto opti
cal) Removable recording medium 2 such as disk, DVD (Digital Versatile Disc), magnetic disk, semiconductor memory, etc.
10 can be temporarily or permanently stored (recorded). Such a removable recording medium 210
Can be provided as so-called package software.

The program can be installed on the computer from the removable recording medium 210 as described above, can be wirelessly transferred from a download site to the computer via a digital satellite broadcasting artificial satellite, or can be connected to a LAN (Local Area). Network) or the Internet, and the program can be transferred to the computer by wire, and the computer can receive the transferred program by the communication unit 208 and install the program on the built-in hard disk 205.

Here, in this specification, processing steps for writing a program for causing a computer to perform various types of processing do not necessarily have to be processed in chronological order in the order described in the flowchart, and may be performed in parallel. Alternatively, it also includes processing executed individually (for example, parallel processing or processing by an object).

Further, the program may be processed by one computer or may be processed by a plurality of computers in a distributed manner. Further, the program may be transferred to a remote computer and executed.

In the above-described embodiment, a case has been described in which, in two digital video signals that are temporally continuous, the absolute value of the difference between the luminance values between the corresponding pixels is calculated and summed. The invention is not limited to this,
For example, the present invention can be widely applied to a case where a cross-correlation for calculating and summing a product of luminance values between corresponding pixels is used.

In the above-described embodiment, a case has been described in which motion detection is performed using image correlation (matching) between two temporally continuous digital video signals. However, the present invention is not limited to this. For example, temporally continuous 2
The present invention can be widely applied to a case where motion detection is performed using a gradient or a phase correlation between two digital video signals.

Further, in the above-described embodiment, a case has been described in which motion detection is performed using image correlation between two temporally continuous digital video signals. However, the present invention is not limited to this. The present invention can be widely applied to a case where motion detection is performed by using image correlation of three or more digital video signals that are consecutive to the above. By doing so, it is possible to perform motion detection with a small fluctuation in the time direction.

Further, in the above-described embodiment, a case has been described in which motion detection is performed using the frame correlation between two temporally continuous digital video signals. However, the present invention is not limited to this. The present invention can be widely applied to a case where a signal is divided into blocks and motion detection is performed using block correlation. This makes it possible to evaluate and determine the motion vector of each block to perform motion detection that more closely matches human visual characteristics.

In the above-described embodiment, a case has been described in which motion detection is performed on a frame signal of a digital video signal. However, the present invention is not limited to this, and motion detection is performed on a field signal of a digital video signal. Can be widely applied. In this case, motion detection may be performed for each field signal, or motion detection may be performed for only one of the field signals. In this way, motion detection can be performed with a smaller amount of calculation.

Further, in the above-described embodiment, a case has been described in which motion information of a digital video signal is detected and an electronic watermark pattern is made to follow the motion information in image analysis in consideration of human visual characteristics. The present invention is not limited to this, and may be combined with a case where edge information or the like of a digital video signal is detected to modulate a digital watermark pattern, or a case where various information such as luminance information or color information of a digital video signal is analyzed and processed. It can be widely applied when performing image analysis.

Also, in the above-described embodiment, a case has been described in which a digital watermark pattern is generated by performing spread spectrum on copyright information using random number data, and this digital watermark pattern is added to a digital video signal.
The present invention is not limited to this. Various electronic watermark embedding methods for superimposing a digital watermark on a baseband signal of a digital video signal, and various electronic watermarks for superimposing a digital watermark on a bit stream signal of a digital video signal. It can be widely applied to the watermark embedding method.

Further, in the above-described embodiment, the case has been described where the copyright information is spectrum-spread using PN-sequence random number data. However, the present invention is not limited to this, and various types of data whose statistical sum is zero are statistically zero. The present invention can be widely applied to the case where the copyright information is modulated in such a manner that it is difficult to analyze the copyright information by the numerical pattern of

Further, in the above-described embodiment, a case where copyright information is superimposed has been described. However, the present invention is not limited to this, and is widely applied to a case where various information is superimposed and transmitted as necessary. be able to.

In the above embodiment, the case where a digital video signal is transmitted from a broadcasting station or the like via a medium such as a satellite wave, a terrestrial wave, or a cable, and the case where a digital video signal is recorded on or reproduced from an optical disk. As described above, the present invention is not limited to this, and can be widely applied to, for example, transmitting various information via the Internet.

The present invention has been described in detail with reference to the specific embodiments. However, it is obvious that those skilled in the art can modify or substitute the embodiment without departing from the spirit of the present invention. That is, the present invention has been disclosed by way of example, and should not be construed as limiting. In order to determine the gist of the present invention, the claims described at the beginning should be considered.

The various processes described in the specification are as follows.
It may be executed not only in chronological order according to the description, but also in parallel or individually according to the processing capability of the device that executes the process or as necessary. Also, in this specification, a system is a logical set configuration of a plurality of devices,
The devices of each configuration are not limited to those in the same housing.

[0189]

As is apparent from the above description, according to the present invention, when performing digital watermark embedding processing on an input digital video signal, a frame correlation is used for a temporally continuous input digital video signal. Based on the detected motion information, the digital watermark pattern is also stopped when the image is stationary, and the digital watermark pattern is also moved when the image is moving, A digital watermark can be superimposed on the input digital video signal so that it is difficult for the human eye to perceive, and without changing the overall embedding strength,
The effect of the digital watermark on the image quality can be effectively suppressed.

Further, according to the present invention, when the digital watermark embedding process is performed on the input digital video signal, motion detection is performed on the temporally continuous input digital video signal using frame correlation, and the detected motion is detected. If the image is moving at a speed at which the human eye cannot detect the still pattern based on the motion information, the digital watermark pattern is stopped, and the image moves at a speed at which the human eye can detect the still pattern. In such a case, the digital watermark pattern can also be moved so as to adaptively reduce the amount of calculation and more efficiently superimpose the digital watermark on the input digital video signal.

Further, according to the present invention, when the digital watermark embedding process is performed on an input digital video signal, motion detection is performed on the temporally continuous input digital video signal using frame correlation, and the motion is detected. The embedding strength when the image is moving is set to be larger than the embedding strength when the image is stationary based on the motion information, and the digital watermark pattern is modulated, thereby improving the detection accuracy of the digital watermark. Thus, the digital watermark can be superimposed on the input digital video signal. As a result, it is possible to effectively suppress the influence of the digital watermark on the image quality, and to secure the reliability of the digital watermark detection.

According to the structure of the present invention, since the movement of an image signal is detected and followed, or the digital watermark information is embedded by adjusting the intensity, the influence on the image quality while ensuring the reliability of detection is reduced. Effectively suppressed digital watermark embedding is possible, and in content distribution in the digital network era, a highly reliable copyright protection system with little image quality degradation can be constructed.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a probability density function of an inner product value for explaining digital watermark detection.

FIG. 2 is a diagram for describing copyright protection processing by embedding and detecting a digital watermark.

FIG. 3 is a diagram illustrating a configuration example of a digital watermark embedding processing apparatus according to the present invention.

FIG. 4 is a diagram illustrating a configuration example of a motion detection unit in the digital watermark embedding processing apparatus of the present invention.

FIG. 5 is a flowchart showing a processing example of the digital watermark embedding processing device of the present invention.

FIG. 6 is a diagram illustrating motion vector detection and digital watermark embedding processing in the digital watermark embedding processing apparatus of the present invention.

FIG. 7 is a diagram illustrating the following of a digital watermark according to the movement of an image in the digital watermark embedding processing apparatus of the present invention.

FIG. 8 is a diagram illustrating a configuration example of a signal modulation unit in the digital watermark embedding processing apparatus of the present invention.

FIG. 9 is a diagram showing a processing flow in the digital watermark embedding processing apparatus of the present invention.

FIG. 10 is a diagram illustrating the adjustment of the digital watermark strength in accordance with the movement of an image in the digital watermark embedding processing apparatus of the present invention.

FIG. 11 is a diagram illustrating a configuration example of a signal modulation unit in the digital watermark embedding processing apparatus of the present invention.

FIG. 12 is a diagram showing a processing flow in the digital watermark embedding processing apparatus of the present invention.

FIG. 13 is a diagram illustrating a configuration example of a digital watermark detection processing device.

FIG. 14 is a flowchart illustrating a processing example of a digital watermark detection processing device.

FIG. 15 is a diagram illustrating an example of a system configuration for executing at least one of digital watermark embedding and detection processing.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 digital watermark embedding device 2 recording device 3 digital watermark detection device 4 digital watermark rewriting device 5 optical disk 6 recording device 7 optical disk 8 optical disk 100 digital watermark embedding processing device 121 PN generation unit 122 multiplication unit 123 motion detection unit 124 signal modulation unit 125 addition Unit 126 signal storage unit 127 correlation calculation unit 128 motion determination unit 129 signal division unit 131 tracking amount setting calculation unit 132 modulation processing unit 141 intensity setting unit 142 modulation processing unit 150 digital watermark detection processing device 151 PN generation unit 152 inner product calculation unit 153 Comparison / determination unit 202 CPU 203 ROM 204 RAM 205 Hard disk 206 Output unit 207 Input unit 208 Communication unit 209 Drive 210 Removable recording medium 212 Keyboard 213 Mouse 214 Keyboard mouse Controller 2061 display device 2062 speaker 2071 Camera 2072 microphone

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shunichi Soma 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation (72) Inventor Takashi Kobashi 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation F term (reference) 5C063 AC01 BA12 CA40 DA20 DB09

Claims (15)

[Claims] An electronic watermark embedding processing device for executing an electronic watermark embedding process on an image signal, an electronic watermark pattern generating means for generating an electronic watermark pattern based on embedding information, and an electronic watermark pattern embedding process target. A motion detection unit that obtains a motion vector based on the image signal and outputs motion information based on the motion vector; and a speed correspondence indicated by the motion information with respect to the digital watermark pattern generated by the digital watermark pattern generation unit. Signal modulating means for executing a modulation process for changing the embedding strength in accordance with the value, and adding means for executing a process for embedding a digital watermark pattern modulated by the signal modulating device into the image signal. An electronic watermark embedding processing device characterized by the above-mentioned. 2. The signal modulating means increases a digital watermark embedding strength with respect to a digital watermark pattern generated by the digital watermark pattern generating means when the motion information indicates that an image is moving. 2. The digital watermark embedding processing apparatus according to claim 1, further comprising a configuration for executing a modulation process of setting the digital watermark embedding strength to be small when the motion information indicates that the image is not moving. 3. The signal modulation unit according to claim 1, wherein the digital watermark pattern generated by the digital watermark pattern generation unit is located in the vicinity of a boundary where the image transitions from a still frame to a moving frame based on the motion information. A configuration in which the digital watermark embedding strength is gradually increased in a plurality of frames, and the modulation processing is set such that the digital watermark embedding strength is gradually reduced in a plurality of frames near a boundary where the image moves from a moving frame to a still frame. 2. The digital watermark embedding processing device according to claim 1, comprising: 4. An information processing apparatus comprising: an intensity setting unit configured to set an embedding intensity of a digital watermark pattern based on a speed corresponding value indicated by the motion information; and an embedding intensity set by the intensity setting unit.
The digital watermark embedding processing apparatus according to claim 1, further comprising: a modulation processing unit configured to execute a modulation processing for setting a digital watermark embedding strength. 5. The correlation detecting means, wherein the motion detecting means reads an image signal for each frame, calculates a correlation between a plurality of temporally continuous image frame data, and outputs correlation information. Motion determining means for calculating a motion vector based on the correlation information to be output, and outputting motion information V based on the calculated motion vector, wherein the signal modulating means generates the digital watermark pattern by the digital watermark pattern generating means. 2. The digital watermark embedding processing apparatus according to claim 1, wherein a modulation process based on the motion information V is performed on the digital watermark pattern. 6. The motion detecting means reads an image signal for each frame, and calculates a correlation between a plurality of temporally continuous image frame data as a sum of absolute values of differences between luminance values of corresponding pixels in the frame. Correlation calculating means for outputting correlation information based on the calculated matching value, and calculating a motion vector having a minimum matching value based on the correlation information output from the correlation calculating means, based on the calculated motion vector. A motion determination unit that outputs motion information V, wherein the signal modulation unit performs a modulation process based on the motion information V on the digital watermark pattern generated by the digital watermark pattern generation unit. The digital watermark embedding processing device according to claim 1, wherein: 7. The signal modulating means according to the digital watermark pattern generated by the digital watermark pattern generating means, in accordance with a speed corresponding value indicated by the motion information, a motion following the motion indicated by the motion vector. 2. The digital watermark embedding processing apparatus according to claim 1, wherein the digital watermark embedding apparatus has a configuration for executing a modulation process for setting a follow-up amount of the digital watermark. 8. A digital watermark embedding method for executing a digital watermark embedding process on an image signal, wherein the digital watermark pattern generating step generates a digital watermark pattern based on the embedding information, and a digital watermark pattern embedding process is performed. A motion detecting step of obtaining a motion vector based on the image signal and outputting motion information based on the motion vector; and a speed correspondence indicated by the motion information with respect to the digital watermark pattern generated in the digital watermark pattern generating step. A signal modulation step of executing a modulation process of changing an embedding strength according to a value; and an addition step of executing a process of embedding a digital watermark pattern modulated in the signal modulation step in the image signal. Digital watermark embedding processing method characterized by the following 9. The digital watermark embedding strength is increased when the motion information indicates that the image is moving with respect to the digital watermark pattern generated in the digital watermark pattern generating step. 9. The digital watermark embedding method according to claim 8, wherein when the motion information indicates that the image is not moving, a modulation process of setting the digital watermark embedding strength to be small is executed. 10. The signal modulating step according to claim 1, wherein the digital watermark pattern generated in the digital watermark pattern generating step is based on the motion information and is located near a boundary where a frame where the image is stationary changes to a frame where the image moves. To execute a modulation process in which the digital watermark embedding strength is gradually increased in a plurality of frames, and the digital watermark embedding strength is gradually reduced in a plurality of frames near a boundary where an image moves from a moving frame to a still image frame. 9. The digital watermark embedding processing method according to claim 8, wherein 11. The signal modulation step includes: an intensity setting step of setting an embedding intensity of a digital watermark pattern based on a speed corresponding value indicated by the motion information; and an embedding intensity set in the intensity setting step. The digital watermark embedding processing method according to claim 8, comprising: a modulation processing step of executing a modulation processing for setting a digital watermark embedding strength. 12. The motion detecting step includes: reading an image signal for each frame, calculating a correlation between a plurality of temporally continuous image frame data, and outputting correlation information; Calculating a motion vector based on the correlation information to be output, and outputting the motion information V based on the calculated motion vector. 9. The digital watermark embedding method according to claim 8, wherein a modulation process based on the motion information V is performed on the digital watermark pattern. 13. The motion detecting step includes the steps of: reading an image signal for each frame, and calculating a correlation between a plurality of temporally continuous image frame data as a sum of absolute values of differences between luminance values of corresponding pixels in the frame. A correlation calculating step of outputting correlation information based on the calculated matching value, and calculating a motion vector having a minimum matching value based on the correlation information output in the correlation calculating step, based on the calculated motion vector. A motion determining step of outputting motion information V, wherein the signal modulating step performs a modulation process based on the motion information V on the digital watermark pattern generated in the digital watermark pattern generating step. The digital watermark embedding processing method according to claim 8, wherein 14. The signal modulation step according to claim 1, wherein the digital watermark pattern generated in the digital watermark pattern generating step includes a motion following the motion indicated by the motion vector according to a speed corresponding value indicated by the motion information. 9. The digital watermark embedding processing apparatus according to claim 8, wherein a modulation process for setting a follow-up amount of the digital watermark is executed. 15. A program for causing a computer system to execute a process of embedding a digital watermark in an image signal, comprising: a digital watermark pattern generating step of generating a digital watermark pattern based on the embedding information; A motion detection step of obtaining a motion vector based on an image signal to be obtained and outputting motion information based on the motion vector; and indicating the motion information for the digital watermark pattern generated in the digital watermark pattern generation step. A signal modulation step of performing a modulation process of changing the embedding strength according to the speed corresponding value; and an addition step of performing a process of embedding the digital watermark pattern modulated in the signal modulation step in the image signal. A program characterized by having .