JP2002171494A - Digital watermark information embedding method and apparatus - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a digital information embedding device capable of embedding a large amount of digital watermark information while reducing the influence on image quality. A digital watermark information embedding apparatus according to the present invention embeds digital watermark information in a code-compressed image signal and sends the digital signal to a digital code compression apparatus in a digital watermark information embedding apparatus. Sometimes MP
The embedding of digital watermark information 13 is performed for each I frame in GOP units of the system layer of the EG image information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for embedding digital watermark information in an image signal to be subjected to digital code compression, and more particularly to a method and apparatus for embedding digital watermark information to reduce the influence on image quality. About.

[0002]

2. Description of the Related Art Conventionally, a digital watermark information embedding device for embedding digital watermark information for protection of copyright and the like is disclosed in, for example, Japanese Patent Application Laid-Open No. 09-191394.

FIG. 7 is a block diagram showing a conventional digital watermark information embedding device.

As shown in FIG. 7, this conventional digital watermark information embedding device is composed of a frequency conversion unit 1, a digital watermark information embedding unit 2, and an inverse frequency conversion unit 3. The frequency conversion of the image signal is performed, the digital watermark information embedded separately is embedded in the digital watermark information embedding unit 2, the inverse frequency conversion is performed in the inverse frequency conversion unit 3, and the digital watermarked image signal is output.

[0005]

However, the conventional digital watermark information embedding device has the following problems. (1) When embedding the same digital watermark information in all image frames, image degradation on B pictures and P pictures code-compressed by MPEG is significant. (2) The amount of digital watermark information that can be embedded in one piece of image data is limited, and large ID information cannot be added. (3) It is premised that digital watermark information is embedded in an image signal in advance, and dynamic digital watermark information cannot be dynamically embedded according to the situation on the receiving side.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem. It is possible to reduce the influence on image quality and to embed a large amount of digital watermark information. Another object of the present invention is to provide a digital watermark information embedding method and apparatus which can further embed digital watermark information in response.

[0007]

A digital watermark information embedding method according to the present invention embeds digital watermark information in a code-compressed image signal and sends the image signal from a transmitting side to a receiving side. At the time of digital code compression, digital watermark information is embedded for each I frame in GOP units of the system layer of MPEG image information.

According to this method, it is possible to avoid embedding the digital watermark information in the B frame and the P frame, and to suppress the image quality deterioration.

The digital watermark information embedding method according to the present invention is a digital watermark information embedding method for embedding digital watermark information in a code-compressed image signal and transmitting the digital watermark information from a transmitting side to a receiving side. Sometimes, the digital watermark information is dispersed into a plurality of image frames, information on the interrelationship between the embedded digital watermark information is also embedded in the digital watermark information, and the receiving side performs the processing based on the information on the interrelationship. The dispersed digital watermark information is reconstructed, and the digital watermark information embedded in the image signal is collectively extracted.

According to this method, digital watermark information can be dispersed and embedded in image frames, and large information over a plurality of images can be embedded as digital watermark information.

The digital watermark information embedding method according to the present invention is a digital watermark information embedding method in which digital watermark information is embedded in a code-compressed image signal and transmitted from a transmission side to a reception side. Sometimes, the digital watermark information is dispersed into a plurality of continuous image frames together with the control code for synchronization, and the receiving side reconstructs the dispersed digital watermark information based on the control code and embeds the digital watermark information in the image signal. The obtained digital watermark information is collectively taken out.

According to this method, digital watermark information can be dispersed and embedded in image frames, and large information over a plurality of continuous images can be embedded as digital watermark information.

The digital watermark information embedding device of the present invention embeds digital watermark information in a code-compressed image signal and transmits the digital watermark information from a transmitting side to a receiving side. Means for transmitting from the receiving side to the transmitting side are provided, and the status of the receiving side is transmitted to the transmitting side to compensate for the loss of the digital watermark information on the receiving side.

With this configuration, the situation on the receiving side can be transmitted to the transmitting side, and the loss of digital watermark information on the receiving side can be compensated.

The digital watermark information embedding apparatus of the present invention embeds digital watermark information in a code-compressed image signal and transmits the digital watermark information from a transmitting side to a receiving side. Means for transmitting from the receiving side to the transmitting side, the receiver information of the receiving side transmitted at regular intervals from the receiving side is embedded as needed in the image signal as digital watermark information, and embedded in the image signal. Secondary management of the image signal is performed based on the recipient information.

With this configuration, it is possible to perform secondary use management of the image signal using the recipient information embedded in the image signal.

Further, the digital watermark information embedding device of the present invention embeds the digital watermark information in a code-compressed image signal, and transmits the digital watermark information from a transmission side to a receiver via a network. Transmitting means for simultaneously transmitting the plurality of receivers to the plurality of receivers, and transmitting means for transmitting individual information from the plurality of receivers to the transmitting side, wherein the reception is transmitted from the receiver at regular intervals. The digital watermark information to be embedded in the image signal is changed as needed based on the individual information of the device, and statistical management of user trends on the network is performed.

With this configuration, the digital watermark information embedded by the transmitting side in the provided image signal is changed at any time based on the individual information of the receiving side provided at regular intervals from the receiver, and statistical management of user trends on the network is performed. It can be performed.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a digital watermark information embedding device according to a first embodiment of the present invention, FIG. 1A is a block diagram of a transmitting side system, and FIG. FIG. 2 shows a block diagram of a receiving system.

As shown in FIG. 1A, an MPEG code compression section 11 compresses an image signal with an MPEG code and converts the image signal into an MPEG code.
Input to the system multiplexing unit 12. When configuring the MPEG system, the MPEG system multiplexing unit 12 extracts a sequence header (hereinafter, referred to as SH), extracts the I frame at the head of the GOP, and inputs the I frame to the digital watermark information embedding unit 13.

The digital watermark information embedding unit 13 converts the digital watermark information received from the outside into the MPEG system multiplex unit 1.
After embedding in the I frame received from MPEG-2, MPEG
Return to the system multiplexing unit 12. MPEG system multiplexing unit 1
Numeral 2 sends to the receiving side as an MPEG stream in which the embedding of digital watermark information is completed.

As shown in FIG. 1B, the MPEG system separating section 14 separates the received MPEG stream, cuts out the SH, extracts the I frame at the head of the GOP, and inputs it to the digital watermark information extracting section 15. . After extracting the digital watermark information, the digital watermark information extracting unit 15
Output to outside of the device. MPEG system separation unit 1
The MPEG stream separated from the MPEG system from FIG. 4 is decoded by the MPEG decoding unit 16,
It is sent out of the device as an image signal. The stream configuration 17 indicates the position of an I frame in which digital watermark information is embedded in the MPEG stream.

Therefore, according to the digital watermark information embedding device of the first embodiment of the present invention, digital watermark information can be embedded only in the first I frame of a GOP in the MPEG system layer. The effect of image quality degradation can be minimized as compared with the case where digital watermark information is embedded in a B frame or a P frame.

FIG. 2 is a block diagram showing a receiving system of the digital watermark information embedding device according to the second embodiment of the present invention.

As shown in FIG. 2, the MPEG system separating section 21 separates the received MPEG stream and
By extracting H, the I frame at the head of the GOP is extracted and input to the watermark information-containing frame selecting unit 22. The digital watermark information-containing frame selecting unit 22 counts up the sequence number of the received I frame, selects an I frame in which the digital watermark information is embedded, and inputs it to the digital watermark information extracting unit 23.

The operation of selecting a frame with digital watermark information will be described in detail.

As shown in FIG. 2A, for example, the first 2 of the digital watermark information embedded in the I frame 26
7, the number of frames up to the I frame 28 in which the next digital watermark information to be distributed is embedded is set in advance on the transmission side.

Frame selection section 22 with digital watermark information
Receives the information of “the number of frames up to the next frame containing the electronic watermark information” at the head 27 of the electronic watermark information from the electronic watermark information extracting unit 23, and skips the I frame to the frame corresponding to the information. In this embodiment, N-1 frames up to frame #N are discarded. Upon receiving the frame #N, the frame selection unit with digital watermark information 22 inputs the frame to the digital watermark information extraction unit 23. The digital watermark information extraction unit 23 extracts the number of frames 29 from the frame 28 up to the next frame with digital watermark information, and inputs the extracted number to the frame selection unit 22 with digital watermark information.

The digital watermark information extracting unit 23 inputs the extracted digital watermark information to the digital watermark information assembling unit 24. The digital watermark information assembling section 24 combines the digital watermark information to assemble the digital watermark information into a form like the digital watermark information 210, and outputs the digital watermark information to the outside of the apparatus. Also, the MPEG system separation unit 21
The G stream is input to the MPEG decoding unit 25,
The EG decoding unit 25 decodes the input stream and outputs it as an image signal to the outside of the device.

Therefore, according to the digital watermark information embedding apparatus according to the second embodiment of the present invention, the digital watermark information is dispersed into a plurality of image frames, and the information of the interrelationship between the embedded digital watermark information is obtained. The digital watermark information can also be embedded in the digital watermark information, and the receiving side can collectively extract the digital watermark information based on the information and embed large digital watermark information that cannot be accommodated by one MPEG I frame.

FIG. 3 is a block diagram showing a receiving system of the digital watermark information embedding device according to the third embodiment of the present invention.

As shown in FIG. 3, the MPEG system separating section 31 separates the received MPEG stream and
By extracting H, the I frame at the head of the GOP is extracted and input to the digital watermark information extraction unit 32. The digital watermark information extracting unit 32 extracts digital watermark information from the received I frame and inputs the digital watermark information to the digital watermark information frame assembling unit 33.

The operation of the digital watermark information frame assembling section 33 will be described in detail.

As shown in FIG. 3A, for example, a start synchronization flag 36 indicating the start of one cycle of digital watermark information is provided at the head 36 of the digital watermark information dispersedly embedded in the I frame 35. Is set on the transmitting side. The digital watermark information frame assembling section 33 searches for the start synchronization flag 36 and starts buffering of the continuous digital watermark information from the frame # 1 with the start synchronization flag 36 as a starting point. Digital watermark information frame assembling unit 3
3 searches for the end synchronization flag 38 while continuing the buffering, and upon receiving the frame 37 having the end synchronization flag 38, the digital watermark information 3 for one cycle.
9 is completed. The digital watermark information frame assembling unit 33 outputs one cycle of digital watermark information 39 to the external device as digital watermark information.

Further, the MPEG system separation unit 31
The PEG stream is input to the MPEG decoding unit 34,
The MPEG decoding unit 34 decodes the input stream and outputs it as an image signal to the outside of the apparatus.

Therefore, according to the digital watermark information embedding device of the third embodiment of the present invention, large digital watermark information that cannot be accommodated by one MPEG I frame can be embedded, and Thus, even from an arbitrary point in the stream, data from the beginning to the end of the digital watermark information can be received within two cycles of the transmission time of the entire embedded digital watermark information.

FIG. 4 is a block diagram of a digital watermark information embedding device according to a fourth embodiment of the present invention, FIG. 4 (A) is a block diagram of a transmission side system, and FIG. FIG. 4C shows a block diagram of the receiving side system, and FIG. 4C shows digital watermark information for one cycle.

As shown in FIG. 4A, the MPEG code compression section 41 compresses the image signal by the MPEG code and inputs it to the system multiplexing section 42. MPEG system multiplexing unit 42
Is used to extract G when configuring the MPEG system.
The I frame at the head of the OP is extracted and input to the digital watermark information embedding unit 43.

The digital watermark information embedding unit 43 embeds the digital watermark information received from the outside into the I frame received from the MPEG system multiplexing unit 42,
Return to the G system multiplexing unit 42. At this time, the digital watermark information embedding unit 43 embeds the digital watermark information start flag and the digital watermark information end flag described in the digital watermark information embedding device according to the third embodiment at the beginning of the digital watermark information. deep. The MPEG system multiplexing section 42 sends the stream to the receiving side as an MPEG stream in which digital watermark information has been embedded.

As shown in FIG. 4B, the MPEG system separating section 44 separates the received MPEG stream, cuts out the SH, extracts the I frame at the head of the GOP, and inputs it to the digital watermark information extracting section 45. . The digital watermark information extracting unit 45 extracts digital watermark information from the received I frame and inputs the digital watermark information to the digital watermark information frame assembling unit 46.

The operation of the digital watermark information frame assembling section 46 will be described in detail.

As shown in FIG. 4C, when the digital watermark information 48 for one cycle is received, for example, upon receiving the end synchronization flag of the digital watermark information #N, the digital watermark information frame assembling unit 46 Then, the validity of the received data is confirmed using error confirmation data such as a CRC embedded in advance. At this time, the received digital watermark information 48
As shown in (1), when a frame is lost in the middle, the digital watermark information frame assembling unit 46 sends a resynchronization request to the digital watermark information embedding unit 43 on the transmission side. Upon receiving the resynchronization request, the digital watermark information embedding unit 43 embeds the digital watermark information into the frame for transmitting the continuous digital watermark information starting from the synchronization flag for starting again, and starts sending the digital watermark information for one cycle.

The MPEG system separation unit 44
The PEG stream is input to the MPEG decoding unit 47,
The MPEG decoding unit 47 decodes the input stream and outputs it as an image signal to the outside of the apparatus.

Therefore, according to the digital watermark information embedding device of the fourth embodiment of the present invention, large digital watermark information that cannot be accommodated by one MPEG I frame can be embedded, and transmission error Also, even if the digital watermark information is lost on the receiving side due to disturbance factors such as stream editing, etc., the correct digital watermark information is embedded in the stream again from an arbitrary point and retransmitted by the notification from the receiving side. be able to.

FIG. 5 is a block diagram of a digital watermark information embedding device according to a fifth embodiment of the present invention, FIG. 5A is a block diagram of a transmission side system, and FIG. FIG. 2 shows a block diagram of a receiving system.

As shown in FIG. 5A, an MPEG code compression section 51 compresses an image signal by MPEG code and inputs the image signal to a system multiplexing section 52. MPEG system multiplexing section 52
Extracts the I frame at the head of the GOP by cutting out the SH when the MPEG system is configured, and inputs it to the digital watermark information embedding unit 53.

The digital watermark information embedding section 53 embeds the user ID information of the receiving side received from the user ID transmitting section 56 of the receiving side system into the I frame received from the MPEG system multiplexing section 52 and then embeds the MPEG system multiplexing section 52. Return to The MPEG system multiplexing section 52 sends the stream to the receiving side as an MPEG stream in which the digital watermark information has been embedded.

As shown in FIG. 5B, the MPEG system separating section 54 converts the received MPEG stream into an MP stream.
Input to the EG decoding unit 55 and the MPEG decoding unit 55
After decoding the input stream, the stream is output to the outside of the apparatus as an image signal.

Therefore, according to the digital watermark information embedding apparatus of the fifth embodiment of the present invention, under the control of the content transmission side, the content such as “when, to whom, and under what conditions” After embedding content management information, the content can be provided to the receiving side, and secondary usage of illegal content on the receiving side can be managed.

FIG. 6 is a block diagram showing a digital watermark information embedding device according to a sixth embodiment of the present invention.

As shown in FIG. 6, the MPEG code compression unit 6
In step 1, the image signal is MPEG-coded and input to the system multiplexing unit 62. The MPEG system multiplexing unit 62
When the EG system is configured, the I frame at the head of the GOP is extracted by cutting out the SH and input to the digital watermark information embedding unit 63.

The digital watermark information embedding section 63 embeds the information from the user terminal 67 received from the control information receiving section 65 into the I frame received from the MPEG system multiplexing section 62, and returns the information to the MPEG system multiplexing section 62. The MPEG system multiplexing section 62 inputs the MPEG stream in which the digital watermark information has been embedded to the on-air sending section 64 as an MPEG stream.
8 to the user terminal 67.

The operation of the control information receiving section 65 will be described in detail.

The user terminal 67 sends the user's individual information (eg, auction bidding price) to the control information receiving unit 65 via the uplink NW 66 at certain intervals. The control information receiving unit 65 statistically processes the collected information from the user terminal 67 (for example, the highest price in the case of an auction) in accordance with the content of the service to be provided, and inputs the processed information to the digital watermark information embedding unit 63. The information processed by the control information receiving unit 65 according to the above processing sequence is embedded in an MPEG stream in real time, and transmitted to the user terminal 67 of the viewer by a broadcast wave 68.

Therefore, according to the digital watermark information embedding apparatus according to the sixth embodiment of the present invention, the transmitting side transmits the provided image signal based on the receiving side individual information provided from the receiver at regular intervals. The digital watermark information to be embedded in the network can be changed at any time, and statistical management of user trends on the network can be performed.

[0057]

According to the digital watermark information embedding method of the present invention, in the digital watermark information embedding method in which digital watermark information is embedded in a code-compressed image signal and transmitted from the transmission side to the reception side, the image signal is digitally compressed. Sometimes MPEG
The embedding of digital watermark information is performed for each I frame in GOP units of the system layer of image information.

According to this method, it is possible to avoid embedding the digital watermark information in the B frame and the P frame, and to suppress the image quality deterioration.

[Brief description of the drawings]

FIG. 1 is a block diagram of a digital watermark information embedding device according to a first embodiment of the present invention, FIG. 1A is a block diagram of a transmitting system, and FIG. 1B is a block diagram of a receiving system;

FIG. 2 is a block diagram of a receiving side system of a digital watermark information embedding device according to a second embodiment of the present invention;

FIG. 3 is a block diagram of a receiving side system of a digital watermark information embedding device according to a third embodiment of the present invention;

FIG. 4 is a block diagram of a digital watermark information embedding device according to a fourth embodiment of the present invention, FIG. 4 (A) is a block diagram of a transmission side system, FIG. 4 (B) is a block diagram of a reception side system,
FIG. 4C is a diagram showing digital watermark information for one cycle.

FIG. 5 is a block diagram of a digital watermark information embedding device according to a fifth embodiment of the present invention, FIG. 5 (A) is a block diagram of a transmitting system, and FIG. 5 (B) is a block diagram of a receiving system;

FIG. 6 is a block diagram of a digital watermark information embedding device according to a sixth embodiment of the present invention;

FIG. 7 is a block diagram of a conventional digital watermark information embedding device.

[Explanation of symbols]

11, 41, 51, 61 MPEG code compression section 12, 42, 52, 62 System multiplexing section 13, 43, 53, 63 Digital watermark information embedding section 14, 21, 31, 44, 54 MPEG system separation section 15, 23 , 32, 45 Digital watermark information extracting unit 16, 25, 34, 47, 55 MPEG decoding unit 17 MPEG stream configuration 22 Frame selecting unit with digital watermark information 24 Digital watermark information assembling unit 33, 46 Digital watermark information frame assembling unit 56 User ID transmitting section 64 On-air transmitting section 65 Control information receiving section 66 Uplink NW 67 User terminal 68 Broadcast wave

Claims (6)

[Claims] In a digital watermark information embedding method for embedding digital watermark information in a code-compressed image signal and transmitting the digital watermark information from a transmitting side to a receiving side, when the image signal is digitally code-compressed, the GOP of the MPEG image information system layer A digital watermark information embedding method, wherein digital watermark information is embedded for each I frame in units. 2. A digital watermark information embedding method for embedding digital watermark information in a code-compressed image signal and transmitting the digital watermark information from a transmitting side to a receiving side when digitally compressing an image signal. Distributed to
The information of the interrelationship between the embedded digital watermark information is also embedded in the digital watermark information, and the receiving side reconstructs the digital watermark information dispersed based on the information of the interrelationship and embeds it in the image signal. Electronic watermark information embedding method, wherein the extracted digital watermark information is collectively extracted. 3. A digital watermark information embedding method for embedding digital watermark information in a code-compressed image signal and transmitting the digital watermark information from a transmitting side to a receiving side when digitally compressing an image signal. Dispersing the digital watermark information into a plurality of continuous image frames together with the code, reconstructing the distributed digital watermark information based on the control code on the receiving side, and collectively extracting the digital watermark information embedded in the image signal. A digital watermark information embedding method. 4. A digital watermark information embedding device for embedding digital watermark information in a code-compressed image signal and transmitting the digital watermark information from a transmitting side to a receiving side, means for transmitting the reception status of the image signal from the receiving side to the transmitting side. Wherein the status of the receiving side is transmitted to the transmitting side to compensate for the loss of digital watermark information on the receiving side. 5. An electronic watermark information embedding apparatus for embedding digital watermark information in a code-compressed image signal and transmitting the digital watermark information from a transmission side to a reception side, means for transmitting a reception status of the image signal from the reception side to the transmission side. The receiver information transmitted from the receiver at regular intervals is embedded in the image signal as digital watermark information as needed, and the receiver information embedded in the image signal is used as the secondary information of the image signal. An electronic watermark information embedding device for performing usage management. 6. A digital watermark information embedding apparatus for embedding digital watermark information in a code-compressed image signal and transmitting the digital signal to a receiver via a network from a transmission side, wherein the image signal is transmitted to a plurality of the receivers simultaneously. Transmitting means for transmitting the individual information from the plurality of receivers to the transmitting side, based on the individual information of the receiver transmitted at regular intervals from the receiver, the image signal An electronic watermark information embedding apparatus, wherein electronic watermark information to be embedded in a network is changed at any time, and statistical management of user trends on the network is performed.