JP6251651B2 - Digital watermark information embedding system, digital watermark information embedding method, and digital watermark information embedding program - Google Patents

Description

  The present invention relates to a technique for embedding and detecting watermark information.

  Currently, there is a digital watermark technology for the purpose of identifying original content, protecting rights associated therewith, providing related information regarding the original content, and the like. Basically, predetermined accompanying information is transmitted as watermark information superimposed on the original content by arithmetic operation or the like, and the watermark information is detected on the receiving side (Non-Patent Document 1).

Katayama, 4 others, “Design of real-time embedded digital watermark for video”, IEICE Technical Report ICSS, Information Communication Security, Vol.112, No.128, July 12, 2012, p.35- 42

  However, depending on the image quality and design of the original image or the like, the detection of the watermark information is hindered due to the interference with the image and the like. Many digital watermarking methods have been proposed so far, but the amount of watermark information superimposed on the original image (the amount of change in pixel values) has been fixed. In other words, since a predetermined fixed amount of watermark information is superimposed on the original image, there is a disadvantage that the watermark information cannot be superimposed in an appropriate amount on the original image having various patterns.

  The present invention has been made in view of the above circumstances, and an object thereof is to appropriately superimpose watermark information.

  In order to solve the above-described problem, the digital watermark information embedding system according to claim 1 includes a superimposing unit that superimposes watermark information on a received image frame, a detection unit that detects watermark information superimposed on the image frame, The gist of the invention is to include an evaluation unit that determines a superimposition amount or a superimposition method of the watermark information based on the detection result of the watermark information and notifies the superimposition unit.

  The electronic watermark information embedding system according to claim 2 is the electronic watermark information embedding system according to claim 1, wherein the evaluation unit changes the amount of superimposition of the watermark information according to whether or not the watermark information can be detected. The gist.

  The digital watermark information embedding system according to claim 3 is the digital watermark information embedding system according to claim 1 or 2, wherein the evaluation unit selects a superimposition method having a different superimposition degree depending on whether or not the watermark information is detected. The gist is to do.

  The digital watermark information embedding system according to claim 4 is the digital watermark information embedding system according to any one of claims 1 to 3, wherein the superimposing means uses the notified superimposition amount or superimposing method to generate the same image frame. The gist of this is to re-superimpose watermark information.

  The digital watermark information embedding system according to claim 5 is the digital watermark information embedding system according to any one of claims 1 to 4, wherein the image frame is an image frame constituting a moving image, and the superimposing means. The gist is to superimpose watermark information on the next and subsequent image frames with the notified superposition amount or superposition method.

  The electronic watermark information embedding system according to claim 6 is the electronic watermark information embedding system according to any one of claims 1 to 5, wherein the detection means determines whether or not the watermark information can be detected based on a detection rate of the watermark information. The gist is to determine.

  The electronic watermark information embedding system according to claim 7 is the electronic watermark information embedding system according to any one of claims 1 to 6, wherein the detecting means changes a pixel value of corresponding pixels between two image frames. The gist is to determine whether or not to detect watermark information based on the amount.

  The electronic watermark information embedding system according to claim 8 is the electronic watermark information embedding system according to any one of claims 1 to 7, wherein the detection means has an image frame or a size of a screen on which the image frame is displayed. Accordingly, the gist is to change the determination reference value used for determining whether or not to detect watermark information.

  The electronic watermark information embedding system according to claim 9 is the electronic watermark information embedding system according to any one of claims 1 to 8, wherein the evaluation unit eliminates a disturbance factor applied to the image frame display device. The gist of the present invention is to determine the amount of watermark information to be superimposed using the environmental value.

  The digital watermark information embedding method according to claim 10, wherein the computer detects the watermark information superimposed on the image frame by the superimposing step of superimposing the watermark information on the received image frame by the superimposing unit, and the detecting unit. The gist of the present invention is to execute a detection step and an evaluation step of determining a superimposition amount or a superimposition method of watermark information based on a detection result of the watermark information and notifying the superimposition unit by an evaluation unit.

  A gist of a digital watermark information embedding program according to an eleventh aspect is to cause a computer to function as the digital watermark information embedding system according to any one of the first to ninth aspects.

  According to the present invention, watermark information can be appropriately superimposed.

It is a figure which shows the whole structure of a digital watermark information embedding system. It is a figure which shows the 1st whole process sequence. It is a figure which shows the 2nd whole process sequence. It is a figure which shows the determination processing flow of a superimposition amount and a superimposition method.

  The present invention evaluates the amount of superimposition and the appropriateness of the superposition method based on the detection result of the watermark information superimposed on the original content, and feeds back an appropriate amount of superimposition. Since the detection result in a predetermined image frame is fed back to the same or another image frame, the content changes sequentially like a moving image, and even for real-time video where the image quality and design cannot be estimated in advance by the conventional method It is possible to embed appropriate watermark information dynamically in a short time. Therefore, it can be sufficiently expected that the watermark information is always stably detected for various types of images. Hereinafter, an embodiment for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing a functional block configuration of a digital watermark information embedding system 1 according to the present embodiment. This digital watermark information embedding system 1 includes an original image transmitting apparatus 100 that distributes an arbitrary moving image, an electronic watermark information superimposing apparatus 200 that superimposes predetermined watermark information on the distributed moving image, an amount of watermark information superimposed, A digital watermark information evaluation apparatus 300 that evaluates the appropriateness of the superimposition method, a video display apparatus 400 that displays a moving image on which watermark information is superimposed, and a watermark information detection terminal 500 that detects watermark information from the displayed moving image. , And is configured.

  Conventionally, the digital watermark information superimposing apparatus 200 directly transmits a moving image on which the watermark information is superimposed to the video display apparatus 400. For example, for a moving image transmitted from a video distribution server of a video distribution company, watermark information such as a URL of a web server describing details of the moving image is imaged and embedded, and an arbitrary one installed in the city Was sent directly to digital signage. When a viewer of the digital signage captures a moving image with a smart terminal, a URL or the like superimposed on the moving image is displayed on the terminal screen.

  On the other hand, in the present embodiment, the digital watermark information evaluation apparatus 300 is interposed between the digital watermark information superimposing apparatus 200 and the video display apparatus 400, and the amount of watermark information superimposed on the image frame and the appropriateness of the superimposing method are included. Are evaluated, and the amount of watermark information to be superimposed is determined based on the evaluation result and notified to the digital watermark information superimposing apparatus 200. The digital watermark information superimposing apparatus 200 superimposes watermark information based on the notified superposition amount or the like. In other words, whether or not the amount of watermark information embedded in an image frame is appropriate is evaluated, and the evaluation result is fed back to optimize the amount of watermark information superimposed. Hereinafter, functions of each device will be described in detail.

  The original image transmitting apparatus 100 is configured to distribute a moving image composed of a plurality of time-series image frames. For example, a video distribution server possessed by a video distributor or the like. In the present embodiment, a moving image is described as an example, but a still image that is a single image frame may be used. The moving image transmission form may be either analog / digital or compressed / uncompressed, and any transmission protocol may be used.

  The digital watermark information superimposing apparatus 200 is configured to superimpose predetermined watermark information on the moving image from the original image transmitting apparatus 100. In the present embodiment, a digital watermark information storage unit 21, a digital watermark generation unit 22, and a digital watermark superimposition unit 23 are provided.

  The digital watermark information storage unit 21 is configured to store original watermark information for generating watermark information. For example, a document describing details of a moving image, a URL of a web server storing the document, an identifier for identifying the validity of a moving image or a still image, and the like. There are no restrictions on the content of the original watermark information, and any information can be used.

  The digital watermark generation unit 22 is configured to acquire original watermark information from the digital watermark information storage unit 21 and generate watermark information imaged with a pattern according to the type of the original watermark information. In order to superimpose the watermark information on the image of the image frame, the original watermark information, which is character information, is converted into an image and encrypted.

  The digital watermark superimposing unit 23 performs the digital watermark generating unit 22 on each image frame of the moving image transmitted from the original image transmitting device 100 based on the superimposition amount and the superimposing method notified from the digital watermark information evaluation device 300. The generated watermark information is superposed by an arithmetic operation or the like. To superimpose means to change the pixel value of the image frame using the pixel value of the watermark information.

  The digital watermark information evaluation apparatus 300 is configured to evaluate the amount of watermark information superimposed by the digital watermark information superimposition apparatus 200 and the appropriateness of the superposition method. In the present embodiment, a digital watermark detection unit 31, a digital watermark evaluation unit 32, and an evaluation information storage unit 33 are provided.

  The digital watermark detection unit 31 is configured to detect watermark information superimposed on an image frame. Specifically, it is detected whether or not the watermark information can be detected, that is, whether or not the original watermark information can be reconstructed from the watermark information and decoded.

  The digital watermark evaluation unit 32 is configured to determine a superimposition amount and superimposition method of watermark information based on the detection result of the watermark information, and notify (feedback) the determined superposition amount and the like to the digital watermark information superimposing apparatus 200. Yes.

  The evaluation information storage unit 33 is configured to store determination rule information and environment information for the digital watermark evaluation unit 32 to determine the amount and method of superimposing watermark information. The decision rule information defines a rule for determining the amount of superimposition based on the detection result of watermark information. The environment information is one parameter of a calculation formula for calculating the amount of watermark information to be superimposed. Environment values for eliminating disturbance factors (for example, reflections generated on the screen due to the influence of fluorescent light, sunlight, etc., whiteout of the video, etc.) occurring on each screen of the video display device 400 and the watermark information detection terminal 500 are offline. Is set in advance.

  The video display device 400 is configured to display a moving image transmitted from the digital watermark information superimposing device 200 via the digital watermark information evaluation device 300. For example, digital signage installed in the city.

  The watermark information detection terminal 500 is configured to detect watermark information from a moving image displayed on the video display device 400. For example, a smart terminal, a mobile phone terminal, or a tablet terminal having an image reading function.

  Each of the devices 100 to 400 includes a storage unit for storing image data, and a transmission / reception unit for transmitting and receiving image data, the determined superposition amount, and the like between the devices. The description is omitted in the drawing of FIG.

  Next, a feedback method of the watermark information detection result / evaluation result will be described. First, the overall processing operation performed in the digital watermark information embedding system 1 will be described. FIG. 2 is a diagram showing a first overall processing sequence.

  First, when the first image frame F1 among the plurality of image frames constituting the moving image is transmitted from the original image transmission device 100, the digital watermark information superimposing device 200 in step S101, the digital watermark information storage unit The original watermark information is read out from 21, and the watermark information imaged with the pattern according to the type of the original watermark information is generated.

  Next, in step S102, the generated watermark information is superimposed on the image frame F1. The watermark information is incidental information to the moving image, and since the area of the imaged watermark information is smaller than the area of the image frame F1, the watermark information is duplicated and the watermark information having the same contents is arranged two-dimensionally. Then, the redundant watermark information is superimposed on the entire image frame F1. Thereby, since all the pixel values of the image frame F1 change as a whole, it is possible to suppress visual discomfort with respect to the moving image.

  Thereafter, in step S103, the superimposed image frame F1 is transmitted to the video display device 400 via the digital watermark information evaluation device 300. Accordingly, the image frame F1 on which the watermark image is superimposed is displayed on the screen of the video display device 400.

  At that time, the digital watermark information evaluation apparatus 300 takes in the image frame F1 from the digital watermark information superimposing apparatus 200 in step S104, and detects the watermark information superimposed on the image frame F1 in step S105. Specifically, the watermark information is extracted from the image frame F1, and it is determined whether the original watermark information can be reconstructed using the extracted watermark information.

  Here, since the watermark information is made redundant, if a part of the original watermark information can be reconstructed, the entire original watermark information can be reconstructed using other information and error correction techniques. Therefore, whether or not the watermark information can be detected may be determined based on the detection rate of the watermark information. For example, it may be determined that the watermark information can be detected at a timing when about 70% of the original watermark information is reconstructed. Thereby, it is possible to shorten the time until the digital watermark information superimposing apparatus 200 is notified of the changed superposition amount and the like. Since the watermark information is digital data, the data contents of the watermark information may be disturbed if there is a packet loss or the like on the network between the original image transmission apparatus 100 and the digital watermark information evaluation apparatus 300. Will not deteriorate.

  Next, in step S106, in order to adjust the amount and method of superimposing the watermark information superimposed by the digital watermark information superimposing device 200, the amount and method of superimposing are determined based on the detection result of the watermark information. The determination method will be described later. Thereafter, in step S107, the determined superposition amount and superposition method are notified to the digital watermark information superimposing apparatus 200.

  Subsequently, when the second image frame F2 is transmitted, the digital watermark information superimposing apparatus 200 is generated in step S101 based on the superimposition amount and superimposing method notified from the digital watermark information evaluating apparatus 300 in step S108. The watermark information thus made is superimposed on the image frame F2. Thereafter, the same processing as in steps S103 to S107 is repeatedly executed. Thereafter, when the third image frame F3 is transmitted, the watermark information is superimposed based on the re-notified superposition amount and superposition method. Thereafter, for all the image frames constituting the moving image, the watermark information is superimposed → the watermark information is detected → the amount of superimposition and the superposition method are determined based on the detection result → the watermark information is superimposed based on the determined superposition amount and the superposition method, Each process is repeatedly executed. Thereby, even if the watermark information is strong or weak in the first image frame, the amount of superimposition is corrected in the subsequent image frames, so that the watermark information can be appropriately embedded as a whole. In addition, video such as moving images can be displayed without delay, and appropriate watermark information can be embedded during video display.

  Here, another method for detecting watermark information performed in step S105 will be described. For example, you may make it consider the influence at the time of seeing the moving image in display with a human eye. Specifically, the previous image frame (the 0th image frame) is held, the amount of change in the pixel value between corresponding pixels with the captured image frame F1, and the amount of change is obtained. If is equal to or greater than the threshold value, it may be determined that the watermark information has been detected. As this threshold value, for example, an average value or a maximum value of all pixels of the watermark information is used.

  Further, the detection rate of the watermark information and the change amount of the pixel value may be changed based on the size of the image frame or the screen of the video display device 400. For example, in the case of a small size such as a smart terminal, the detection rate / change amount (determination reference value) is reduced, and in the case of a large size such as a movie screen, it is increased.

  Furthermore, the detection accuracy of these detection rates and change amounts may be used. An arithmetic expression is used to obtain detection accuracy, and each parameter of the arithmetic expression may be given a weight according to the parameter type, or each parameter value may be changed dynamically or statically. Also good.

  So far, the first overall processing operation has been described. In the first example, the example in which the watermark information is superimposed on all the image frames has been described. However, in the case of a moving image, since the image frames are continuously displayed repeatedly, the watermark information is not necessarily superimposed on all the image frames. There is no need. Therefore, the digital watermark information superimposing apparatus 200 skips step S108 and superimposes the watermark information on the third image frame after the first image frame F1, thereby reducing the number of image frames to be superimposed. May be. Thereby, the delay until the display by the watermark information superimposing process can be eliminated.

  Next, the second overall processing operation will be described. FIG. 3 is a diagram showing a second overall processing sequence.

  First, when the first image frame F1 is transmitted from the original image transmission apparatus 100, the digital watermark information superimposing apparatus 200 generates watermark information and superimposes it on the image frame F1 in steps S201 to S204. The image frame F1 is temporarily held and transmitted to the digital watermark information evaluation apparatus 300.

  Next, in step S205, the digital watermark information evaluation apparatus 300 determines whether the original watermark information can be reconstructed from the watermark information superimposed on the image frame F1. If reconstructed, the image frame F1 is transferred to the video display device 400 in step S206. If reconstruction is not possible, in step S207 to step S209, the superimposition amount and superposition method are determined and notified to the digital watermark information superimposing apparatus 200, and then the image frame F1 is discarded.

  Thereafter, in step S210, the digital watermark information superimposing apparatus 200 superimposes the watermark information on the image frame F1 held in step S203 based on the superimposition amount and superimposition method notified from the digital watermark information evaluation apparatus 300 (superimposition). Rework). Thereafter, the image frame F1 on which the watermark information is superimposed is transmitted to the digital watermark information evaluation apparatus 300. Thereafter, until the original watermark information is reconstructed from the watermark information of the image frame F1, the process of superimposing the watermark information on the image frame F1 is repeatedly executed. Thereby, since the watermark information can be detected from any image frame displayed on the video display device 400, the detection accuracy of the watermark information at the watermark information detection terminal 500 can be improved.

  So far, the second overall processing operation has been described. In each of the first and second overall processing operations, the watermark information is superimposed on the entire image frame. However, the watermark information may be superimposed only on a part of the image frame. Further, when the image quality of the original image is deteriorated by superimposing the watermark information, the watermark information may not be superimposed on an image frame in which the image quality is deteriorated. For example, when there is an adjacent pixel having a pixel value that is more than a threshold within a pixel region where watermark information is to be superimposed, the watermark information superimposing process is skipped. For example, if the pixel value range is 256 gradations from 0 to 255, 250 is used as the threshold value. This is because if the pixel values of adjacent pixels are as far as 250, there is a high possibility of including the foreground and the background, and if watermark information is superimposed on such an edge portion, there is a possibility of blurring on the video.

  Next, the watermark information superimposition amount and superposition method determination method performed by the digital watermark information evaluation apparatus 300 will be described in detail. FIG. 4 is a diagram showing a determination processing flow of the amount and method of superimposing watermark information. This decision processing flow is defined in advance in decision rule information.

  First, when an image frame is received in step S301, the digital watermark detection unit 31 determines whether the watermark information superimposed on the image frame has been detected in step S302. In the case of the above example, it is determined whether or not about 70% of the original watermark information has been reconstructed from the watermark information. If reconstruction is possible, the process proceeds to step S303, and if reconstruction is not possible, the process proceeds to step S304.

  Next, in step S303, since the watermark information can be detected from the image frame, the digital watermark evaluation unit 32 considers that the superimposition method and the superposition amount having a lower superposition degree than the current superposition method and the superposition amount may be used. A superimposition method having the next lowest superimposition degree is selected from a plurality of superposition methods prepared in advance, and a superposition amount smaller than the current superposition amount is determined as a new superposition amount.

  Any method can be used for the superposition method. For example, (1) a simple superimposition method in which watermark information is calculated and superimposed on the luminance and chromaticity of a pixel, and (2) a portion that is difficult to be visually recognized, such as a high-frequency component (such as a fine pattern) or a yellow component of an image. (3) Time to disperse and superimpose in a plurality of image frames because there is a risk of being conspicuous when superimposed on a single image frame constituting a moving image. There are superposition methods that take into account the characteristics. Since the degree of superimposition for one image frame is the lowest in the method (3) and the highest in the method (1), if the current superposition method is the method (1), the method is changed to the method (2).

  Also, the superposition amount can be calculated using an arbitrary calculation formula. For example, when the calculation formula is “superimposition amount = (parameter value A + parameter value B) × environment value C”, the parameter values A and B are changed to be smaller than the current value to reduce the superposition amount. At this time, a weight value corresponding to the type of parameter may be assigned to each of the parameter values A and B. The environment value C is a value of environment information set offline. Since the environmental value C is included in the parameters of the calculation formula, a disturbance factor generated on each screen of the video display device 400 and the watermark information detection terminal 500 can be eliminated.

  In addition, a calculation formula of “superimposition amount ′ = superimposition amount × correction value D” may be used. The correction value D is a value for adjusting so that there is no sense of incongruity when a person views a video in which watermark information is embedded. When the calculated amount of superimposition is larger than a certain value, there is a possibility that a visually uncomfortable feeling may occur. Therefore, the amount of superimposition is finely adjusted in order to eliminate the discomfort.

  On the other hand, in step S304, since the watermark information could not be detected from the image frame, the digital watermark evaluation unit 32 considers that the superimposition method and superposition amount having a higher superposition degree than the current superposition method and superposition amount should be used, and is prepared in advance. The superposition method having the next highest superposition degree is selected from the plurality of superposition methods, and the superposition amount higher than the current superposition amount is determined as the new superposition degree.

  Thereafter, in step S305, the digital watermark evaluation unit 32 notifies the digital watermark superimposing unit 23 of the digital watermark information superimposing apparatus 200 of the superposition amount and superposition method determined and selected in step S303 or step S304.

  Thereafter, the process returns to step S301, and steps S302 to S305 are repeatedly executed every time an image frame is received. In particular, in step S303 and step S304, the superposition amount (including parameter values for obtaining the superposition amount) and the superposition method after the change and the superposition method are retained, and the superposition amount and the superposition method retained each time the process is repeated. A new superposition amount and superposition method are calculated with reference to. As a result, when the state in which the watermark information is not detected continues, the superposition amount and the superposition degree of the superposition method are increased as needed until the watermark information is detected in two stages, three stages,. On the other hand, when the state where the watermark information is detected continues, it is pulled down. Therefore, since the amount and method of superimposing watermark information on moving images are adjusted until they are fixed, and even when the video scene changes, the amount of watermark information is superimposed and the method of superimposition is optimal. Can be

  So far, the determination method of the superposition amount and the superposition method has been described. In addition, although the example which changes both a superposition amount and a superposition method was demonstrated, you may change only any one. Also, in the digital watermark information superimposing apparatus 200, there is no superiority or inferiority in the order of applying the changed superposition amount and superposition method, and either one may be applied first.

  Furthermore, in addition to the determination rules described above (determination processing flow in FIG. 4) and the parameters of the superposition amount calculation formula, other rules that can be dynamically added and changed according to the characteristics of the original image and new Further parameters may be used. As a result, it is possible to more appropriately determine the amount of watermark information to be superimposed on a live video or the like for which it is difficult to estimate the quality of the original image in advance without further degrading the quality.

  As described above, according to the present embodiment, the digital watermark superimposing unit 23 superimposes the watermark information on the image frame transmitted from the original image transmitting apparatus 100, and the digital watermark detecting unit 31 is superimposed on the image frame. Since the watermark information is detected and the digital watermark evaluation unit 32 determines the amount or method of superimposing the watermark information based on the detection result of the watermark information and notifies the digital watermark superimposing unit 23 of the watermark information, the watermark information can be appropriately superimposed. This effect will be described in detail below.

  The process of determining the amount of watermark information superimposition after confirming the contents of the original image in advance is determined by rules based on experience, etc., and therefore depends on the skill of the person performing the watermark information superimposition processing. . However, by using the present invention, it is possible to superimpose watermark information of a certain quality regardless of the skill of the practitioner.

  In addition, in order to confirm the contents of the original image in advance, at least the actual time for reproducing the original image is required, and then the watermark information is superimposed, so that the real time is not completed until the processing is completed. Twice or more time is required. On the other hand, according to the present invention, since the superimposition process is performed while determining the superimposition amount and the superimposition method of the watermark information while reproducing the original image, the entire processing time can be greatly shortened. For example, even for an original image whose contents cannot be grasped in advance, such as live video, by using the present invention, watermark information with a constant quality can be obtained in a short time regardless of the skill of the person who performs the superimposition processing. Can be superimposed.

  Finally, the digital watermark information superimposing apparatus 200 and the digital watermark information evaluation apparatus 300 described in the present embodiment can be constructed as a program, installed in a computer and executed, or distributed via a communication network. is there.

DESCRIPTION OF SYMBOLS 1 ... Digital watermark information embedding system 100 ... Original image transmission apparatus 200 ... Digital watermark information superimposition apparatus 21 ... Digital watermark information storage part 22 ... Digital watermark generation part 23 ... Digital watermark superimposition part 300 ... Digital watermark information evaluation apparatus 31 ... Digital watermark Detection unit 32 ... digital watermark evaluation unit 33 ... evaluation information storage unit 400 ... video display device 500 ... watermark information detection terminal S101 to S108, S201 to S210, S301 to S305 ... step

Claims (10)

Superimposing means for superimposing watermark information on the received image frame;
Detecting means for detecting watermark information superimposed on the image frame;
An evaluation unit that determines a superimposition amount or a superimposition method of watermark information based on the detection result of the watermark information, and notifies the superimposition unit ;
The detection means includes
An electronic watermark information embedding system, wherein a determination reference value used for determining whether or not to detect watermark information is changed according to an image frame or a screen size on which an image frame is displayed . The evaluation means includes
2. The digital watermark information embedding system according to claim 1, wherein the amount of watermark information superimposed is changed according to whether or not the watermark information can be detected. The evaluation means includes
3. The digital watermark information embedding system according to claim 1, wherein a superposition method having a different superposition degree is selected depending on whether or not the watermark information can be detected. The superimposing means includes
4. The digital watermark information embedding system according to claim 1, wherein watermark information is re-superimposed on the same image frame by the notified superposition amount or superposition method. The image frame is an image frame constituting a moving image,
The superimposing means includes
5. The digital watermark information embedding system according to claim 1, wherein watermark information is superimposed on the next and subsequent image frames by the notified superposition amount or superposition method. The detection means includes
6. The digital watermark information embedding system according to claim 1, wherein whether or not the watermark information can be detected is determined based on a watermark information detection rate. The detection means includes
7. The digital watermark information embedding system according to claim 1, wherein whether or not to detect watermark information is determined based on a change amount of a pixel value between corresponding pixels between two image frames. The evaluation means includes
8. The digital watermark information embedding system according to claim 1, wherein an amount of watermark information to be superimposed is determined using an environmental value for eliminating a disturbance factor applied to an image frame display device. Computer
A superimposing step of superimposing watermark information on the received image frame by the superimposing means;
A detection step of detecting watermark information superimposed on the image frame by detection means;
An evaluation unit that determines an amount or method of superimposing watermark information based on the detection result of the watermark information, and performs an evaluation step of notifying the superimposing unit;
In the detection step,
An electronic watermark information embedding method, wherein a determination reference value used for determining whether or not to detect watermark information is changed according to an image frame or a screen size on which an image frame is displayed. A digital watermark information embedding program for causing a computer to function as the digital watermark information embedding system according to any one of claims 1 to 8.

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