KR100850775B1 - Data structure, apparatus and method for controlling copy of Audio-visual data - Google Patents

Abstract

Disclosed is a data structure, apparatus and method for copy control of AV data in accordance with the present invention.

A data structure for copy control of AV data according to the present invention includes AV data having a format according to a protocol for a digital channel between a transmitting device and a receiving device, and copy control information for controlling copying of the AV data. .

According to the present invention as described above, copy control is possible for digital signals received and decoded by the DVI or HDMI protocol, and when converting the digital signals into analog signals, CGMS and macrovision signals for the analog signals can be inserted. Can be.

DVI, HDMI, CGMS, Macrovision, Piracy Protection

Description

Data structure, apparatus and method for controlling copy of Audio-visual data

1 is a block diagram showing the configuration of an HDMI source device and an HDMI sink device according to the prior art;

2 is a conceptual diagram illustrating a data structure for copy control of AV data according to an embodiment of the present invention;

3 is a diagram showing a data structure of copy control information according to another embodiment of the present invention;

4A and 4B show the contents of data byte 1 of the embodiment shown in FIG.

5A and 5B show the contents of data byte 2 of the embodiment shown in FIG.

6 is a block diagram showing the configuration of a transmitting device and a receiving device for copy control of AV data according to an embodiment of the present invention;

7 is a flowchart illustrating a copy control method in a transmission device according to an embodiment of the present invention;

8 is a flowchart illustrating a copy control method in a receiving device according to an embodiment of the present invention;

9 is a diagram for explaining operations of a transmitter and a receiver for copy control of AV data according to an embodiment of the present invention;

10 illustrates a signal structure of AV data according to an embodiment of the present invention.

The present invention relates to copy control of AV data, and more particularly, to a media transmission device having a data structure for preventing unauthorized copying of AV data in a device using a digital channel, and a copy control function using the data structure. A device and a method for controlling AV data copying in the devices.

Recently, when transmitting AV data from a digital media playback device (source device) to a display device or a recording device (sink device), DVI (Digital Video), a protocol for transmitting pure digital signals without an analog signal between the devices, is used. Interfaces (HDMI) and High Definition Multimedia Interface (HDMI) are widely used. The DVI and HDMI protocols protect content using High-Bandwidth Digital Content Protection (HDCP), an encryption technology made by Intel. HDCP prevents illegal copying of data and prevents data leakage to a third device through encryption and decryption of AV data transmitted from a source device to a sync device. Therefore, to export images to the projector via an HDCP DVD player using a DVI or HDMI connection, the projector must be equipped with an HDCP module. Also, to display content on two projectors simultaneously, a DVI or HDMI distribution amplifier must be equipped with an HDCP module.

1 is a block diagram illustrating a configuration of an HDMI source device and an HDMI sink device according to the prior art.

HDMI source devices are playback devices such as digital set-top boxes or DVD players. Referring to FIG. 1, the source device 110 transmits AV data generated through the video processor 112, the video scaler 114, and the like to the sink device 120 through the HDMI TX 116 which is a signal transmitter. The HDMI TX 116 is a block for converting an AV signal into HDMI Transition Minimized Differential Signaling (TMDS) format, and includes an HDCP scrambler that encrypts AV data. The HDMI TX 116 transmits the encrypted data through an HDMI interface, which is a digital channel.

The HDMI sink device refers to a device or a display device that records the received AV data in HDD, DVD-R or BD-R. Referring to FIG. 1, the sink device 120 includes an HDMI RX 122 that is a signal receiver. The HDMI RX 122 is a block for converting the data of the HDMI TMDS format into a general AV signal, and performs an HDCP authentication process for receiving a digital signal from the source device 110 and decoding the received signal. If you do not succeed in HDCP authentication, you will not be able to decrypt the password and you will not see the normal screen. For HDCP authentication, it is necessary to compare R0 and R0 'between the HDMI TX 116 and the HDMI RX 122 to confirm whether they match. In order to obtain R0 and R0 'between the HDMI devices 110 and 120, a key value called a key selection vector (KSV) is exchanged with each other, and this becomes a key for decryption. The HDCP authentication process does not end once but repeats every few milliseconds while the video is being viewed.If the R0 and R0 'do not match between the two devices (110, 120), the screen is invisible and the content is protected by this principle. do.

Referring to FIG. 1, the AV data outputted as a result of authentication completion in the HDMI RX 122 is input to the digital video processor 124, processed, displayed or recorded, or input to the D / A converter 126. Is converted into an analog signal and then displayed or recorded. That is, up to the point of time input to the D / A converter 126 is a section 130 existing as a digital signal, and thereafter, an analog signal section 140.

As described above, the content is protected by using HDCP in the DVI or HDMI protocol, but since there is no restriction in copying the AV data after the HDCP authentication is successfully completed and decrypted in the recording device operating as an HDMI sink device, After that, there is a problem that piracy is possible indefinitely. In addition, when the decoded HDMI signal is converted into an analog signal, there is a problem that there is no way to protect the analog signal from illegal copying. That is, in FIG. 1, a technique capable of controlling radiation for a digital signal passing through the HDMI RX 122 is required.

The present invention is to solve the above problems, to provide a data structure capable of controlling the copy of the AV data successfully authenticated according to the protocol for the digital channel, and to provide a copy control device and method using the data structure The purpose.

One feature of the present invention for solving the above problems is, in the data structure for copy control of AV data, AV data having a format according to a protocol for a digital channel between a transmitting device and a receiving device, and the AV It includes copy control information for controlling copying of data.

Preferably, the copy control information includes information for controlling copying of a digital signal output after the receiving device receiving the AV data has successfully authenticated the AV data according to a protocol for the digital channel. Include.

Preferably, the copy control information, when the receiving device receiving the AV data converts the digital signal outputted after the authentication process for the AV data successfully according to the protocol for the digital channel into an analog signal; Contains information for generating a copy control signal to be inserted into the analog signal. Preferably, the copy control signal to be inserted into the analog signal is a signal according to the CGMS (Copy Generation Management System) protocol and / or the Macrovision protocol.

Preferably, the AV data is in a format according to the HDMI (High Definition Multimedia Interface) protocol. Preferably, the copy control information is inserted in the Data Island Period of the AV data.

Preferably, the AV data is in a format conforming to the DVI (Digital Visual Interface) protocol.

According to another aspect of the present invention, a method of controlling copying of the AV data in a transmitting device transmitting AV data to a receiving device through a digital channel, the digital signal including the AV data according to a protocol for the digital channel And inserting information for controlling the copying of the AV data into the generated digital signal.

According to still another aspect of the present invention, there is provided a method of controlling copying of AV data at a receiving device that receives AV data from a transmitting device through a digital channel, the method comprising: receiving a digital signal according to a protocol for the digital channel; Authenticating the received digital signal according to a protocol for the digital channel, extracting copy control information stored in a predetermined register as a result of the authentication process, and referring to the extracted copy control information. And controlling copying of the AV data.

Advantageously, controlling the copying of the digital signal comprises generating and inserting a copy control signal into the analog signal when converting the AV data into an analog signal. Preferably, the step of generating and inserting the copy control signal includes generating and inserting a signal according to a copy generation management system (CGMS) protocol and / or a macrovision protocol into the analog signal.

A further aspect of the present invention provides a transmission device having a signal transmitter for transmitting AV data to a receiving device through a digital channel, wherein the copying of the AV data is controlled to a digital signal generated according to a protocol for the digital channel. And a microprocessor for controlling the signal transmitter to insert and transmit copy control information.

Another feature of the invention is a receiving device having a signal receiver for receiving a digital signal from a transmitting device over a digital channel and authenticating the received digital signal according to a protocol for the digital channel, wherein the authentication process is performed. Extracting copy control information stored in a predetermined register as a result, and referring to the extracted copy control information, a microprocessor for controlling copying of the AV data.

Preferably, the receiving device further comprises a D / A converter for converting the AV data output as a result of the authentication process into an analog signal, wherein the microprocessor is configured for the analog signal with reference to the copy control information. Generate a copy control signal and control the D / A converter to insert the copy control signal into the converted analog signal.

Hereinafter, exemplary embodiments of the present invention will be described with reference to the accompanying drawings.

2 is a conceptual diagram illustrating a data structure for copy control of AV data according to an embodiment of the present invention.

Referring to FIG. 2, an information storage medium including data according to the present invention includes an AV data 200 having a format according to a protocol for a digital channel between a transmitting device as a source device and a receiving device as a sink device, and the AV data. Copy control information 210 for controlling copying. The AV data 200 is preferably data generated in a DVI or HDMI format. The copy control information 210 is information for controlling the copying of the digital signal outputted after the signal receiver of the sink device receiving the AV data successfully authenticates the AV data according to the protocol for the digital channel. Therefore, it is used to generate a radiation control signal to be inserted into the analog signal when converting the digital signal output from the signal receiver into an analog signal. In addition, the copy control information 210 is preferably inserted as part of the DVI or HDMI format so that the data structure according to the present invention is compatible with the DVI or HDMI format. For example, it can be inserted in the Data Island Period of the HDMI protocol.

3 is a data structure of copy control information according to another embodiment of the present invention, and illustrates a structure of a Samsung Video Content Protection (SVCP) packet inserted into a digital signal transmitted according to an HDMI protocol. When recording using the digital signal input through the above-mentioned HDMI RX or performing D / A conversion, it is necessary to comply with the copy control information recorded in the SVCP.

Referring to FIG. 3, the SVCP packet consists of 9 bytes in total. Areas containing copy control information are data byte 1 (Data Byte 1, 310) and data byte 2 (Data Byte 2, 320), and the remaining areas are type information (SVCP TYPE CODE) and version information (SVCP Version Number). ), Length of packet (Length of SVCP), checksum information (Data Byte 0), and the like are recorded.

A predetermined type code is recorded in the 'SVCP TYPE CODE' field. 1 is recorded in the 'SVCP Version Number' field, and an incremented number will be recorded when a later version is changed. In the 'Length of SVCP' field, the number of bytes of data of the SVCP packet is recorded. The checksum value of the SVCP packet is recorded in the 'Data Byte 0' field, and the checksum value is set to be 0 when the checksum value is subtracted from the sum of all bytes including the 'SVCP TYPE CODE' field. The information on the CGMS and the aspect ratio is recorded in the first data byte 310 field, and the APSs 324 and 326 and the ASB 322 are recorded in the second data byte 320 field. Data bytes 3 to 5 are reserved areas.

The copy control information recorded in the first data byte 310 and the second data byte 320 is used to control the copy of the digital signal output from the signal receiver of the sink device. Optionally, this information can be used to generate a radiation control signal for the analog signal when converting the digital signal into an analog signal at the sink device. For example, it is used to generate signals according to the Copy Generation Management System (CGMS) protocol and / or the Macrovision protocol. The CGMS protocol defines information about whether to allow copying of analog content. In case of NTSC (National Television System Committee) method, CGMS signal is inserted into 20th line and 283th line and PAL (Phase Alternation Line) method into 43rd progressive line. It is intended to indicate whether to allow, copy only once, or not to copy. In addition, according to the CGMS signal, macrovision, a copy protection technology, is performed. Macrovision is a technique that adds a series of electrical pulses to a video signal so that it does not appear when playing back the original videotape, but degrades significantly when playing back the tape.

4A and 4B show the contents of data byte 310 of the embodiment shown in FIG.

Referring to FIG. 4A, whether to allow copy is recorded in bit 1 316 and bit 0 318 of the data byte 310. That is, information such as whether copying is allowed, copying is not possible, or only one copying is allowed. Referring to FIG. 4B, the screen ratio and the screen display format are recorded in the fourth bit 314 and the fifth bit 312 of the first data byte 310, respectively.

5A and 5B show the contents of data byte 320 of the embodiment shown in FIG.

Referring to FIG. 5A, four types of macrovision are recorded in bit 1 324 and bit 0 326 of data byte 320, and referring to FIG. 5B, data byte 320 is described. Bit 4 (322) records whether the analog prerecord package media is a DVD, and this information is referenced to generate a macrovision signal.

The transmission device and the reception device according to the present invention have a configuration similar to that of the conventional device, and are preferably connected by a DVI or HDMI cable supporting a protocol for a digital channel. However, it differs from the conventional apparatus in that the microprocessor or microcontroller of the two apparatuses processes the copy control information according to the present invention. Therefore, the data structure of the AV data according to the present invention can be used even in a conventional device, and has perfect compatibility.

FIG. 6 is a block diagram illustrating a configuration of a transmitting device and a receiving device for copy control of AV data according to an embodiment of the present invention, and is an example of a device supporting HDMI.

Referring to FIG. 6, the HDMI transmitting device 610 according to the present invention includes an HDMI signal transmitter 612 for transmitting AV data to the receiving device 620 through a digital channel. The microprocessor 614 controls the signal transmitter 612 to insert and transmit copy control information for controlling the copying of the AV data in the digital signal generated according to the protocol for the digital channel. The copy control information may be inserted in the data island period of the HDMI signal.

Referring to FIG. 6, the HDMI receiving device 620 according to the present invention receives a digital signal from the transmitting device 610 through a digital channel and authenticates the received digital signal according to a protocol for the digital channel. Receiver 622 is provided. Since the copy control information inserted in the HDMI signal is recorded in a predetermined register (not shown) by the HDMI RX 622, the microprocessor 624 of the sink device 620 stores the information in this register in a memory (not shown). ) To control the copying of AV data. As a register for storing copy control information, a predetermined register (for example, InfoFrame) among the registers of the HDMI RX IC 622 may be used.

In addition, according to the embodiment, a D / A converter 626 for converting the AV data output as a result of the authentication process into an analog signal may be further included. At this time, the microprocessor 624 generates a copy control signal for the analog signal with reference to the extracted copy control information, and controls the D / A converter 626 to insert the copy control signal into the analog signal.

7 is a flowchart illustrating a copy control method in a transmission device according to an embodiment of the present invention.

Referring to FIG. 7, the transmitting device generates a digital signal including AV data according to a DVI or HDMI protocol (702). Information for controlling the copying of the AV data is inserted into the generated digital signal (704). The inserted copy control information is information separate from the data structure or authentication information defined in the protocol for the digital channel such as DVI or HDMI, and is for controlling the post copy of the AV data decoded according to the protocol. The digital signal in which the copy control information is inserted is transmitted to the receiving device which is the sink device (706) and reproduced or copied to the recording medium.

8 is a flowchart illustrating a copy control method in a receiving device according to an embodiment of the present invention.

Referring to FIG. 8, first, a digital signal including AV data is received from a transmission device as a source device (802). The received digital signal is authenticated and decrypted by the HDMI RX according to the protocol for the corresponding digital channel (804). At this time, since the copy control information inserted into the HDMI signal by the transmitting device is stored in a predetermined register by the HDMI protocol, the copy control information is extracted from this register (806). Next, the copy of the AV data is controlled with reference to the extracted copy control information (808). In the case of converting and recording AV data into analog, a copy control signal for CGMS and macrovision is generated and inserted into the analog signal based on the copy control information.

9 illustrates operations of a transmitting device and a receiving device for copy control of AV data according to an embodiment of the present invention.

Referring to FIG. 9, first, a video signal and an audio signal are input to an HDMI TX IC 910 from an AV device such as a DVD or a set top box (①, ②). The CGMS information of the video signal is already decoded by the MPEG IC or the like and transmitted to the microcontroller 916 (3). The microcontroller 916 generates SVCP packet data with reference to the input CGMS information and then writes the SVCP packet data in the register 914 (④, ⑤). The encoder / serializer 912 of the HDMI TX IC 910 converts the input video data, the audio data, and the SVCP packet data into the TMDS format and outputs the data through the HDMI cable (6). At this time, the SVCP packet data is transmitted in a data island period of channel 1.

The TMDS signal transmitted through the HDMI cable is separated into a plurality of signals at the decoder 922 of the HDMI RX IC 920. SVCP packet data among the separated signals is recorded in the register 924 (7). Among the separated signals, video data and audio data are input to a video processor or video encoder 928. The microcontroller 926 reads SVCP packet data from the register 924 (8), performs copy control with reference to the read data (9), or the CGMS and the analog video signal output from the video encoder 928. Insert a macrovision pulse or the like (⑩).

10 illustrates a signal structure of AV data according to an embodiment of the present invention, and shows a structure of a digital signal transmitted through an HDMI cable. There is a Data Island Period (1002) in the empty space other than the Video Data Period, and various packet data is inserted and transmitted therein. SVCP packets according to the present invention may also be carried in the Data Island Period 1002.

The method according to the present invention as described above can be embodied as computer readable codes on a computer readable recording medium.

So far I looked at the center of the preferred embodiment for the present invention. Those skilled in the art will appreciate that the present invention can be implemented in a modified form without departing from the essential features of the present invention. Therefore, the disclosed embodiments should be considered in descriptive sense only and not for purposes of limitation. The scope of the present invention is shown in the claims rather than the foregoing description, and all differences within the scope will be construed as being included in the present invention.

According to the configuration of the present invention as described above, copy control is possible even for digital signals received and decoded by the DVI or HDMI protocol.

Also, when converting the digital signal into an analog signal, a CGMS and a macrovision signal for the analog signal may be inserted.

In addition, the structure of the AV data according to the present invention is compatible with the conventional DVI and HDMI protocols.

Claims (23)

delete delete delete delete delete delete delete delete delete delete delete delete A method for controlling copying of AV data at a receiving device that receives AV data from a transmitting device through a digital channel, Receiving a digital signal according to a protocol for the digital channel; Authenticating the received digital signal according to a protocol for the digital channel; Extracting copy control information stored in a predetermined register as a result of the authentication process; And controlling copying of the AV data by generating and inserting a copy control signal into the analog signal when converting the AV data into an analog signal with reference to the extracted copy control information. Copy control method. The method of claim 13, The generating and inserting of the copy control signal may include generating and inserting a signal according to a copy generation management system (CGMS) protocol and / or a macrovision protocol into the analog signal. How to control copying of data. delete delete delete delete delete A receiving device having a signal receiver for receiving a digital signal from a transmitting device through a digital channel and authenticating the received digital signal according to a protocol for the digital channel, A microprocessor that extracts copy control information stored in a predetermined register as a result of the authentication process, and controls copying of the AV data with reference to the extracted copy control information; And And a D / A converter for converting the AV data output as a result of the authentication process into an analog signal, The microprocessor generates a copy control signal for the analog signal with reference to the copy control information, and controls the D / A converter to insert the copy control signal into the converted analog signal. device. The method of claim 20, The copy control signal for the analog signal, characterized in that the signal according to the CGMS (Copy Generation Management System) protocol and / or Macrovision (Macrovision) protocol. The method of claim 20, The digital channel is a receiving device, characterized in that the digital interface according to the HDMI (High Definition Multimedia Interface) protocol. The method of claim 20, The digital channel is a receiving device, characterized in that the digital interface according to the DVI (Digital Visual Interface) protocol.

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