HK1068000B - Apparatus for processing digital data and copy protection method - Google Patents

Description

Digital data processing apparatus and copy prevention method

The present application is a divisional application of the invention application entitled "copy prevention method and apparatus for digital video system" in chinese patent application No.95120356.8 filed on 26.11/1995: the filing date of this patent application is filed on a divisional application entitled "copy prevention method and recording apparatus for digital data processing and recording system" on 3/20/2003 under the application number 03107336.0.

Technical Field

The present invention relates to a digital data processing apparatus for processing digital data and a copy protection technique for a recording system, and a recording medium for recording digital data in the system. And more particularly to a copy protection method for a digital VCR, in which encryption codes are introduced into the VCR to display an image only in the VCR including a corresponding encryption code therein, thereby preventing a magnetic tape from being copied; and to a recording medium having information for controlling the operation of a copy protection function in a digital data processing apparatus.

Background

Common copy protection methods for analog VCRs are disclosed in U.S. patent nos. 4819098, 4571642 and 4577216.

First, us patent 4819098 discloses a method in which an interference signal is inserted into a video waveform in an automatic gain control circuit (AGC) of a VCR. Here, the inserted signal does not affect the AGC of its monitor, but does affect the AGC of a VCR recording a precise level of signal on a video tape.

In us patent 4571642 a method is disclosed in which a phase noise or other correction signal is inserted into the color burst of a video waveform.

However, all known techniques use the difference between the circuitry of a monitor and the corresponding circuitry of a VCR to insert the distributed signal into the analog signal. Some VCRs can make normal copies despite copy protection. Some monitors cannot display the image of the original video tape. Copy protection, which is commonly introduced into an analog VCR system, is difficult to apply to a Digital Storage Medium (DSM).

Particularly in a satellite receiver or a high definition TV decoder, as shown in fig. 2, an MPEG bit stream received by a digital VCR is constructed to separately or simultaneously transmit a transport header, a packetized unit bit stream (PES) header, and audio and video data.

The PES header includes a PES header feature bit field of 14 bits and a PES header field having a variable length, where 14 bits is a field for DSM like a digital VCR. The PES header feature bit region includes: 1 bit Copyright (CR) feature bit, 1 bit original Or Copy (OC) feature bit, 2 bits PD feature bit, 1 bit TM feature bit, and 1 bit AC feature bit.

The PES header field varies in length and is partially provided with PD, TM, and AC feature bits, and if the value of the PD feature bit is "00", there is no PTS/DTS area. If the value is "10", it is 40 bits. If the value is "11", then the region is 80 bits. If the TM feature bit is "0", then no DSM policy mode field exists. If the TM flag is "1", then the field is 8 bits. If the AC signature bit is "1", then an additional copy information field is 8 bits.

When video data recorded and compressed using a satellite receiver or a high definition TV decoder is encoded in the encoder 101, it is converted into a packet form in the packet processing section 102, as shown in fig. 1. If compressed audio data is encoded in the audio encoder 103, the data is converted into a packet form in the packet processing section 104.

When the outputs of the packet processing sections 102 and 104 are multiplexed in the transport multiplexer 105, a fixed transport stream shown in fig. 2 is output to a digital VCR. In this case, in order to protect against copying, it is proposed in us patent 4200770 to apply a public cryptographic encryption code. It solves the drawbacks in cipher management or cipher distribution when a conventional unit cipher or stream cipher algorithm like the Data Encryption Standard (DES) uses only one secret cipher for encryption or decryption.

The public cipher encryption system makes all users U possess special encryption algorithm E^PKu and decryption algorithm D^PKu. In this case, the encryption algorithm E for public encryption^PKu is disclosed as a public password to the password providing section 107. Decryption algorithm D for secret passwords^PKu remains secret. E^PKu and D^PKThe characteristics of u are as follows.

First, according to all users U and the transmitted information m, D^PKu(E^PKu(m))＝m。

Second, encryption algorithm E^PKu and decryption algorithm D^PKu does not require complex calculations.

Third, from encryption algorithm E^PKu in D^PKU to satisfy D^PK*u(E^PKu (m)) ═ m is not possible.

In the encryption system having the above-described feature, as shown in fig. 3, when the user a transmits the information m to the user B, the common password algorithm E for the common password of the user B' received from the password supply section 107^PK _BThe encryptor 106 pair information m (E)^PK _B(m) c) and transmits the result to the decryption 109 by means of a common channel. Here, the common channel represents a channel in which data transmitted is not secured.

Cipher decoder 108 receiving cipher information from cipher providing section 107 outputs and addsCipher algorithm E^PKB corresponds to an algorithm D^PKB, decryption algorithm D for decryptor 109^PK _BDecrypt the encryptor 106 output (D)^PK _B(c) M) and then transmitted to the user B. In other words, only user B can match with encryption algorithm E^PK _BRelative decoding algorithm D^PK _BAnd (6) decrypting.

One principle that is improved by public key encryption is disclosed in us patent 4405829. Such public cryptographic encryption systems are known as RSA systems. A method for efficiently computing RSA public key encryption using batch processing is disclosed in us patent 4964164.

However, such public cryptographic encryption is not applicable to high-speed encryption. One CA system is to prevent illegal copying. However, there is no way to protect programs provided via a digital storage medium in a digital VCR.

Disclosure of Invention

It is, therefore, an object of the present invention to provide an illegal copy prevention method for a digital video system, in which control copy information and data recording are both recorded on a digital medium, so that only a reproducing apparatus that can detect the control copy information can normally reproduce the digital medium, thereby preventing illegal copying.

In order to achieve the above object of the present invention, there is provided a copy preventing method comprising the steps of: (a) generating copy control information for controlling a copy prevention operation and identification information for indicating the presence of the copy control information, the copy control information indicating whether copying of the digital data is permitted; and (b) recording the copy control information, the identification information, and the digital data on the digital recording medium.

In order to achieve the above object of the present invention, there is provided a copy preventing method comprising the steps of: (a) receiving copy control information necessary for determining copy permission of the digital content; and (b) selectively recording the digital content on the digital recording medium based on a state of the received copy control information, wherein when the copy control information indicates that copying is not permitted, the recording step is not performed, and when the copy control information indicates that copying is permitted at least once, the recording step is performed, and when the recording step is performed, updated copy control information and identification information indicating that the copy control information is contained are also recorded on the digital recording medium.

In order to achieve the above object of the present invention, there is provided a copy preventing method comprising the steps of: (a) reading control data recorded in the digital recording medium, the control data including copy control information indicating whether copying of the digital content recorded on the digital recording medium is permitted and an identifier indicating whether the copy control information exists; and (b) outputting copy control information based on the identifier to be effectively controlled in the recording and/or reproducing apparatus.

In order to achieve the above object of the present invention, there is provided a copy preventing method comprising the steps of: detecting indication information indicating whether or not there is copy control information necessary for determining whether or not to allow copying of the digital content; detecting copy control information based on the indication information; and controlling the copy prevention function based on the detected copy control information.

In order to achieve the above object of the present invention, there is provided a copy preventing method comprising the steps of: determining whether copy control information is present based on identification information indicating whether the copy control information is present, the copy control information indicating whether copying of the digital content is permitted; detecting copy control information based on the identification information, wherein the identification information and the copy control information are detected from a control data portion followed by the digital content; and controlling a copy prevention function of the digital content based on the copy control information.

In order to achieve the above object of the present invention, there is provided a recording medium comprising: a copy control information area including an identifier to indicate whether copy control information is included, for identifying the presence of the copy control information, and copy control information to indicate whether copying of the digital data is permitted; and a digital data area that is decomposed into a plurality of first data units including a plurality of second data units each including a header portion and a data portion.

In order to achieve the above object of the present invention, there is provided a recording medium comprising: a digital data area, which is divided into a plurality of first data units including a plurality of second data units each including a header portion and a data portion, each of the second data units including a header portion and a data portion. Wherein the header portion includes copy control information indicating whether copying of the digital data is permitted, and an identifier indicating whether the copy control information is included so as to identify the presence of the copy control information.

In order to achieve the above object of the present invention, there is provided a recording medium comprising: a digital data area which is divided into a plurality of first data units, the first data units including a plurality of second data units each including a header portion and a data portion; and a copy control information area for storing copy control information indicating whether copying of the digital data is permitted and an identifier indicating whether the copy control information is included so as to identify the presence of the copy control information, wherein the copy control information area is followed by the first data unit.

In order to achieve the above object of the present invention, there is provided a copy preventing method comprising the steps of: detecting copy control information necessary for determining whether to allow copying of the digital content; determining whether to record the digital content based on a state of the copy control information; and if the status of the copy control information indicates that copying of the digital content is permitted, updating the copy control information to indicate that a copy was made.

In order to achieve the above object of the present invention, there is provided a copy preventing method comprising the steps of: detecting indication information indicating whether or not there is copy control information necessary for determining whether or not copying of the digital data is permitted; detecting copy control information based on the indication information; and determining whether to record the digital data based on the state of the copy control information.

In order to achieve the above object of the present invention, there is provided a copy preventing method comprising the steps of: generating copy control information necessary for determining whether to allow copying of the digital content and an identifier identifying whether the copy control information is included; the digital content, the identifier and the copy control information are transmitted.

In order to achieve the above object of the present invention, there is provided an apparatus for processing digital data, comprising: a detecting unit for detecting an identifier indicating whether or not copy control information is included so as to identify the presence of the copy control information, which is necessary for determining whether or not copying of the digital data is permitted; and a controller for controlling the copy prevention function based on a state of the copy control information.

In order to achieve the above object of the present invention, there is provided an apparatus for processing digital data, comprising: a detection unit for detecting a header portion followed by a data portion; an extracting unit for extracting, from the detected header portion, an identifier indicating whether or not copy control information is included in the header portion so as to identify the presence of the copy control information, and copy control information necessary for determining whether or not to permit copying of the digital data; and a controller for controlling the copy prevention function based on the state of the extracted copy control information.

In order to achieve the above object of the present invention, there is provided an apparatus for processing digital data, comprising: a transmission section for transmitting the digital data, an identifier indicating whether or not copy control information is included so as to identify the presence of the copy control information, and copy control information necessary for determining whether or not to allow copying of the digital data; an interface for transmitting and/or receiving digital data, an identifier and copy control information; and a receiving part for receiving the digital data, the identifier and the copy control information through the interface, wherein the receiving part comprises: a detection unit for detecting the identifier and the copy control information from the transmitted digital data, and a controller for controlling the copy prevention function based on a state of the detected copy control information.

Drawings

Fig. 1 is a block diagram of a conventional packet processing apparatus;

fig. 2 is a diagram showing an example of a general transmission bit stream;

FIG. 3 is a block diagram of a conventional public cryptographic encryption system;

FIG. 4 is a system connection diagram illustrating the present invention;

FIG. 5 is a block diagram of a copy protection apparatus for a digital video system of the present invention;

FIG. 6 is a block diagram of the copy protection information detector of FIG. 5;

FIG. 7 is a circuit diagram of the PES header detector of FIG. 6;

FIGS. 8a-8f are waveform diagrams of inputs/outputs on various portions of FIG. 7;

FIG. 9 is a circuit diagram of the copy protection information separator of FIG. 6;

FIGS. 10a-10g are waveform diagrams of inputs/outputs on corresponding portions of FIG. 9; and

fig. 11a-11d show an example of a bit stream according to the invention.

Detailed Description

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

Referring to fig. 5, a copy prevention apparatus of the present invention includes: a reproducing section 1 for reproducing data recorded on the magnetic tape; a cipher insertion section 2 for prepending a tape title start code and a cipher information set to the bit stream of the reproduction section 1; a decoding section 3 for decoding the output of the cipher inserting section 2 and transferring it as parallel data; a cipher check/correction section 4 for detecting a cipher information group from the parallel data transmitted from the decoding section 3; a copy prevention information detection section 5 for detecting a PES header from the detected cipher information group and separating copy prevention information; a copy prevention information correction section 6 for correcting, if necessary, an output of the copy prevention information detection section 5; an encryption section 7 for encrypting an output of the copy prevention information correction section 6; and a recording section 8 for recording the output of the encryption section 7 on the magnetic tape.

As shown in fig. 6, the copy prevention information detecting section 5 includes: a PES header detecting section 10 for searching parallel data in synchronization with a clock clk to detect PES headers, and a copy prevention information separator 20 which is activated by a PES header signal of the PES header detecting section 10 to detect a copy prevention information field.

Referring to fig. 7, the PES header detection section 10 includes: first and second flip-flops 11 and 12 for sequentially delaying parallel data according to a clock clk; a packet start code detector 13 for retrieving the parallel data and the outputs of the first and second flip-flops 11 and 12 to detect a packet start code of the PES header; a bit stream ID detector 14 for retrieving the output of the second flip-flop 12 to detect the bit stream ID of the PES header; a delay 15 for sequentially delaying the output is-pscp of the start code detector 13 according to a clock clk, and a detection signal generator 16 for logically multiplying the output of the delay 15 and the output of the bitstream ID detector 14 and outputting a PES header detection signal is-PES-header.

As shown in fig. 9, the copy prevention information separator 20 includes: a D-flip-flop 21 for holding the parallel data output from the PES header detector 10; a D-flip-flop 22 for holding a PES header detection signal is-PES header of the PES header detector 10; a D-flip-flop 23 cleared by the output of the D-flip-flop 22 for holding a voltage (+5V) by a CR signal output from the D-flip-flop 21 and outputting a signal LCR; a D-flip-flop 24 cleared by the output of the D-flip-flop 22 for holding a voltage (+5V) by an OC signal output from the D-flip-flop 21 and outputting a signal LOR, a copy information prevention position operator 25 for retrieving parallel data of the PES header detector 10 and calculating the position of an additional copy information field; a counter 26 for counting the output of the copy information position operator 25, and a D-flip-flop 27 for holding an additional copy information field of the output of the D-flip-flop 21.

The operation and effect of the present invention will be described below. In the case of reproducing or copying recorded data on a magnetic tape in general, a connection between two systems is made as shown in fig. 4.

Through these connections, an MPEG bit stream reproduced by the VCR a is input to a satellite receiver or a high definition TV so that it cannot be recognized whether the bit stream is displayed on a screen or input to the VCR B and recorded on another video tape.

To this end, according to the present invention, in the case where a bit stream reproduced by VCR a is copied by VCR B, the copy-protected information is transferred from VCR a to VCR B. VCR B analyzes this information recorded with the bitstream.

Here, the insertion position of the copy prevention information included in a GA bit stream is very limited because it should not affect the decoding of a satellite receiver or a decoder of a high definition TV so that an image is normally displayed on a monitor. The copy protection information may be inserted into the front end of the MPEG bitstream or into the PES header.

When MPEG bit streams are decoded in units of a group of pictures (GOP), their GOP start codes are used to cause the corresponding GOPs to be classified. This is useful when transferring initialization data to a record-side VCR, because decoding is not affected even when a small amount of data is added to the front end of the MPEG bitstream.

It is useful to insert copy protection information into the PES header in the repeat transport information because copy protection of a recording medium such as DSM is determined using the CR and OC characteristic bits of the PES header and the additional copy information field. In this case, there are various anti-copy methods.

First, when a mode of "Copy impossible" ("No Copy") is detected from the additional Copy information field of the PES title, the VCR B cannot enter its recording mode.

Second, when a mode of "copy permitted" is detected for copy prevention such as the DAT mode, the VCR B starts recording, but the "copy impossible" mode is recorded in the additional copy information field to interrupt the re-copy from a copy tape. This means that: a second source strip can be formed from the original strip, i.e. the first source strip, but a third source strip cannot be formed.

Third, for "Back-up Copy", tape B copied by VCR B can only be reproduced normally in VCR A. According to this method, the reproduction-side VCR a encrypts the bit stream with its own inherent password and records it on the magnetic tape, so that only the reproduction-side VCR a can decrypt the MPEG bit stream recorded on the magnetic tape. For each VCR device, a special password is set which is encrypted by the VCR's password and recorded on the magnetic tape B. However, the VCR device used to record tape B is VCR B and tape B is encrypted by VCR a's password, so that VCR a's password requires a GA bit stream to be transmitted to VCR B.

Therefore, when the cryptographic information of the VCR a is transmitted as a title before the bit stream in the "backup copy", it is recorded on the front end of the magnetic tape B, which satisfies the above-mentioned insertion position of the copy prevention information.

Here, as shown in fig. 2, the additional copy information field position is changed in the PES header according to whether a Presentation Time Stamp (PTS)/decode time stamp (PTS) and a DSM policy approach field are present. The location of this change must be compensated for. Here, the information transmitted by the additional copy information is a copy prevention method to be performed by the VCR B on the recording side.

In the case of recording the bitstream shown in fig. 11a in the method of "backup copy", the format of the bitstream recorded on the magnetic tape is determined as shown in fig. 11 b.

Here, a header area added to the front of the MPEG bit stream is formed with a tape header start code, i.e., a header identification code, and a cipher information group for storing cipher information. In the case of encrypting an MPEG bit stream in units of a GOP, the encrypted units are classified by using a packet start code header and a bit stream ID of a PES header. The encryption unit is a basic unit of encryption, and the encryption unit can be changed regardless of whether encryption is performed in the encryption unit, and the unit selected by the encryption algorithm and the password. Here, the encryption unit does not have to be encrypted up to the additional copy information field of the PES header. The encryption is performed after the copy information field is appended until the end of the encryption unit. The first "transfer header" is not encrypted.

The operation of "backup copy" by titling will be described below.

First, in the reproduction, when the recorded data of the magnetic tape a is encrypted, the reproduction-side VCR a decrypts it with the encryption information of the encryption information group to generate the information m. Its cryptographic information is added to the header and transmitted in the format of fig. 11 c.

The recording-side VCR B records the cipher information transmitted from the reproducing-side VCR a in the title of the copy tape B and then records the encrypted bit stream. Here, when the password information is transferred from the reproduction side to the recording side, a common password encryption can be used for the system for reliability because the information can be disclosed to an illegal dubber.

Even if the public key is disclosed, such a public key encryption system ensures the confidentiality of data because a large number of calculations cannot be processed in real time. Therefore, this system is not suitable when the MPEG bit stream is directly encrypted. "backup copy" can be accomplished when the MPEG bit stream is encrypted using a unit cipher algorithm such as DES or a bit stream cipher algorithm and a used cipher is encrypted in public cipher encryption.

In this case, each VCR u includes an encryption algorithm E corresponding to the public key^PKu and a decryption algorithm D corresponding to the secret code^PKu. Encryption algorithm E^PKu uses a valid password (a powe key) of VCR u, and decrypts algorithm D^PKu uses an internal password for VCR u.

Here, the internal password may be publicly disclosed. Since the other VCR encrypts with the internal password, the reproduction-side VCR a transmits the internal password on the password information group of the title. The recording side VCRB randomly selects a password Y used in a unit cipher algorithm such as DES and uses an external password E^PK _ATo encrypt it. The result is recorded on the encryption information group of the copy tape B.

The data is sequentially divided into encryption units and encrypted and recorded with a unit cipher algorithm using a cipher Y. In this way the bit stream of fig. 11d is recorded on the copy tape B.

When the copy tape B is reproduced in the reproduction-side VCR A, the decryption code D in which the data is appropriately decrypted is used^PK _A[E^PK _A(Y)]The password Y can be recovered. In other VCRs, no password could be foundY, which cannot decode the bitstream.

An embodiment of the invention shown in fig. 5 for performing this operation will be described below.

When reproduction for tape reproduction starts, the reproduction section 1 detects data recorded on the magnetic tape as shown in fig. 11a and amplifies the data by a predetermined level. As shown in fig. 11b, the cipher insertion section 2 adds a title having a tape title start code and a cipher information set to the GA bit stream of the reproduction section 1 shown in fig. 11 a. The copy protection information is added to the additional copy information field of the PES header to form the format shown in fig. 11 c. Here, the decoding section 3 decodes the bit stream formed in the cipher insertion section 2 and transmits it as parallel data to the recording-side VCR by means of an interface.

When the bit stream of fig. 11c is transferred to the recording-side VCR via the interface, the cipher detection/correction section 4 detects the cipher information group added to the bit stream and corrects the cipher information group if necessary.

The copy prevention information detection section 5 searches the PES header area to detect the additional copy information field. Here, although a small amount of information is recorded in the additional copy information region, redundant information is recorded in several regions of the bitstream in order to increase reliability of information transmission.

The copy prevention information detection section 5 separates the value of the AC flag from the PES header flag to calculate the position of the additional copy information field because the position varies in the PES header. Here, when the copy prevention information correction section 6 corrects the output of the copy prevention information detection section 5, the encryption section 7 performs encryption using a unit encryption algorithm such as DES. Here, the copy prevention information correction section 6 performs correction and the input data is stored in one RAM. Accordingly, the encryption section 7 records the encrypted bit stream on the magnetic tape in the recording section 8. Since the encryption information of the reproduction-side VCR is added to the copy tape, only the VCR having such encryption information can normally reproduce the magnetic tape.

As shown in fig. 6, in the copy protection information detecting section 5, the PES header detecting section 10 retrieves the output of the password detecting/correcting section 4 and outputs a header detection signal is-PES-header. When the title detection signal is-PES-title is input, the copy prevention information separator 20 detects the additional copy information field and the OC and CR flag bits.

A PES header detector 10 for detecting PES headers is formed as shown in fig. 7. When the bit data stream data-in is inputted as shown in fig. 8a, the first flip-flop 11 synchronized with the clock clk delays for a predetermined time to output the delayed bit data stream as shown in fig. 8 b. The second flip-flop 12 delays the output of the first flip-flop 11 by a predetermined time and outputs the delayed bit stream as shown in fig. 8 c.

Here, the packet start code detecting section 13 retrieves the bit stream shown in fig. 8a and the outputs of the first and second flip-flops 11 and 12 shown in fig. 8b and 8c in order to detect the packet start code of the PES header. When the detection signal is-pscp is output as shown in fig. 8d, the delay 15 connected therein as a multi-stage flip-flop sequentially delays the detection signal is-pscp according to the clock clk.

Meanwhile, the bitstream ID code detector 14 retrieves the output of the second flip-flop 12 and detects the bitstream ID area of the PES header. Then, the detection signal is-sid shown in fig. 8e is output to the detection signal generator 16. The detection signal generator 16 logically multiplies the outputs of the delay 15 AND the bit stream ID code detector 14, AND the flip-flop holds the output of the AND gate in accordance with the clock clk, so that the PES header detection signal is-PES-header is output to the copy prevention information separator 20 as shown in fig. 8 f.

Here, a copy prevention information separator 20 for detecting copy prevention information is formed, as shown in fig. 9. When the parallel data output from the PES header detector 10 and shown in fig. 10a is held and output as shown in fig. 10b, the D-flip-flop 22, which is synchronized with the PES header detection signal is-PES-header of the PES header detector 10 shown in fig. 8f, holds the voltage of +5V, so that a HIGH signal is output to the clear terminals of the D-flip-flops 23, 24, and 27 to release the clear state.

The D-flip-flop 23 is synchronized with the CR characteristic phase of the output of the D-flip-flop 21 shown in fig. 10b to hold the voltage Vcc so that a HIGH signal LCR is output as shown in fig. 10 c. The D-flip-flop 24 is synchronized with the OC characteristic bit of the output of the D-flip-flop 21 to hold the voltage Vcc so that a HIGH signal LOC is output, as shown in fig. 10D.

The copy prevention position detector 25 retrieves the characteristic bits of PD, TM, and AC of the parallel data of the PES header detector 10 shown in fig. 10a to calculate the position of the additional copy information field, the result of which is output to the counter 26, as shown in fig. 10 e. The calculator 26 receiving the 4-bit value counts so that a HIGH signal is output at a predetermined count value, as shown in fig. 10 f.

The D-flip-flop 27, which is synchronized with the HIGH output rco of the counter 26, holds an additional copy information field of the parallel data from the D-flip-flop 21 shown in fig. 10 b. This information field is output as shown in fig. 10 g.

As described above, in the copy prevention method and apparatus for a digital video system of the present invention, a cipher information is recorded with a bit stream so that a VCR having the cipher information normally reproduces a magnetic tape, thereby preventing illegal copying of the magnetic tape. Further, for the transmission of the password information, a common password encryption code is introduced so that an illegal copier cannot release the copy prevention, thereby increasing the reliability of the copy prevention.

Claims (61)

1. An anti-copy method, comprising the steps of:

(a) generating copy control information for controlling a copy prevention operation and identification information for indicating the presence of the copy control information, the copy control information indicating whether copying of the digital data is permitted; and

(b) the copy control information, the identification information, and the digital data are recorded on a digital recording medium.

2. The method of claim 1, further comprising:

the digital data is decomposed into at least a plurality of first data units and then recorded based on the data units.

3. The method of claim 2, wherein the first data unit comprises a unit of at least one group of picture unit formed in MPEG data.

4. A method according to claim 3, wherein the first data unit is broken down into a plurality of second data units each comprising a header portion and a data portion.

5. The method of claim 4, wherein the copy control information and the identification information are recorded in a header portion of the second data unit.

6. The method of claim 2, further comprising:

a control data unit is added to a first data unit including at least one image group unit, and then the control data unit and the first data unit are recorded in a digital recording medium.

7. The method of claim 6, wherein the copy control information and the identification information are contained within a control data unit.

8. The method of claim 1, further comprising:

receiving original copy control information; and

determining whether copying of the digital data is permitted based on the original copy control information, wherein

The steps (a) and (b) are performed only when the original copy control information indicates that the copying is allowed.

9. The method of claim 8, wherein the copy control information indicates that copying is not allowed in step (a).

10. An anti-copy method, comprising the steps of:

(a) receiving copy control information necessary for determining copy permission of the digital content; and

(b) selectively recording the digital content on a digital recording medium based on a state of the received copy control information,

wherein when the copy control information indicates that copying is not permitted, the recording step is not performed, and when the copy control information indicates that copying is permitted at least once, the recording step is performed, and when the recording step is performed and the copy control information is updated, updated copy control information and identification information indicating that the copy control information and the updated copy control information are included are information that changes the received copy information to reflect that recording of the digital content has been performed are also recorded on the digital recording medium.

11. The method of claim 10, wherein the encrypted content is recorded in step (b).

12. The method of claim 10, wherein the updated copy control information indicates that no more copies are allowed.

13. The method of claim 12, wherein the updated copy control information and the identification information are recorded in a control area followed by the digital content.

14. The method of claim 10, wherein the digital content is recorded as a unit including a header portion and a data portion, and the copy control information and the identification information are recorded within the header portion of the digital content.

15. The method of claim 10, wherein the copy control information and the identification information are recorded in an area followed by the digital content, the digital content being decomposed into image group units.

16. The method according to claim 14 or 15, wherein the digital content is encrypted content.

17. An anti-copy method, comprising the steps of:

(a) reading control data recorded in the digital recording medium, the control data including copy control information indicating whether copying of the digital content recorded on the digital recording medium is permitted and an identifier indicating whether the copy control information exists; and

(b) copy control information is output based on the identifier to be effectively controlled in the recording and/or reproducing apparatus.

18. The method of claim 17, wherein the digital recording medium is a recordable or rewritable medium.

19. The method according to claim 18, wherein the copy control information has been updated and the copy control information having the updated state has been recorded on the recording medium.

20. The method of claim 19, wherein the updated status indicates that no more copies are allowed.

21. The method of claim 20, wherein the state is updated in a case where the digital content has been recorded when a previous state of the copy control information indicates "one copy generation is allowed".

22. The method of claim 17, further comprising:

whether to record the digital content is determined based on the copy control information.

23. An anti-copy method, comprising the steps of:

detecting indication information indicating whether or not there is copy control information necessary for determining whether or not to allow copying of the digital content;

detecting copy control information based on the indication information; and

the copy prevention function is controlled based on the detected copy control information.

24. The method of claim 23, wherein the copy protection function includes digital content recording, the digital content recording being performed when the copy control information indicates that at least one copy is allowed, and the digital content recording being not performed when the copy control information indicates that no more copies are allowed.

25. The method of claim 24, further comprising:

the updated copy control information is recorded together with the digital content when the recording is performed, wherein the update status indicates that no more copies are allowed.

26. The method of claim 25, wherein the digital content is recorded as a plurality of units each preceded by a header portion.

27. The method of claim 26, wherein the copy control information is recorded in a header portion.

28. The method of claim 25, wherein the copy control information is recorded in an area followed by the digital content, and the digital data is decomposed into image group units.

29. The method of claim 27, wherein the copy protection function includes digital content reproduction, the digital content reproduction including the steps of: the digital content is output together with the copy control information so that operation control is performed based on the copy control information in the recording mode.

30. The method of claim 29, further comprising:

the identification information followed by the copy control information is output.

31. The method of claim 29, wherein the reproducing step includes a decryption process for the encrypted digital content.

32. An anti-copy method, comprising the steps of:

determining whether copy control information is present based on identification information indicating whether the copy control information is present, the copy control information indicating whether copying of the digital content is permitted;

detecting copy control information based on the identification information, wherein the identification information and the copy control information are detected from a control data portion followed by the digital content; and

the copy prevention function of the digital content is controlled based on the copy control information.

33. The method of claim 32, wherein the copy protection function includes digital content recording, the digital content recording being performed when the copy control information indicates that at least one copy is allowed, and the digital content recording being not performed when the copy control information indicates that no more copies are allowed.

34. The method of claim 33, further comprising:

if recording is performed, the updated copy control information is recorded together with the digital content, wherein the update status indicates that no more copies are allowed.

35. The method of claim 34, wherein the digital content is recorded as a plurality of units each preceded by a header portion.

36. The method of claim 35, wherein the copy control information is recorded in a header portion.

37. The method of claim 36, wherein the copy protection function includes digital content reproduction, the digital content reproduction including the steps of: the digital content is output together with the copy control information so that operation control is performed based on the copy control information in the recording mode.

38. The method of claim 33, further comprising:

the identification information followed by the copy control information is output.

39. The method according to claim 33 or 37, wherein the copy protection function comprises encryption or decryption of encrypted digital content.

40. An anti-copy method, comprising the steps of:

detecting copy control information necessary for determining whether to allow copying of the digital content;

determining whether to record the digital content based on a state of the copy control information; and

if the status of the copy control information indicates that copying of the digital content is permitted, the copy control information is updated to indicate that a copy was made.

41. The method of claim 40, further comprising:

the updated copy control information, the identifier indicating the presence of the copy control information, and the digital content are recorded on the recording medium.

42. The method of claim 41, wherein the updated copy control information and the identifier are recorded in an area of a start portion of the digital content or a header portion of the digital content, the digital content being divided into the header portion and the data portion.

43. The method of claim 40, wherein the updated copy control information indicates that no more copies are allowed.

44. The method of claim 42, wherein the detecting step detects the copy control information based on a flag indicating whether the copy control information exists.

45. An anti-copy method, comprising the steps of:

detecting indication information indicating whether or not there is copy control information necessary for determining whether or not copying of the digital data is permitted;

detecting copy control information based on the indication information; and

based on the state of the copy control information, it is determined whether to record digital data.

46. The method of claim 45, further comprising:

if the copy control information indicates that at least one copy is permitted, the digital data, the identifier, and the updated copy control information are recorded on the recording medium.

47. The method of claim 46, wherein the updated control information indicates that no more copies are allowed.

48. The method of claim 47, wherein the updated copy control information and the identifier are recorded on an area followed by digital data of the image group unit.

49. The method of claim 47, wherein the digital data is recorded in a plurality of packets, the packets respectively including a header portion and a data portion,

wherein the updated copy control information and the identifier are recorded in a header portion followed by a data portion.

50. An anti-copy method, comprising the steps of:

generating copy control information necessary for determining whether to allow copying of the digital content and an identifier identifying whether the copy control information is included;

the digital content, the identifier and the copy control information are transmitted.

51. The method of claim 50, wherein the digital content is transmitted in a plurality of packet units, the packet units each including a header portion and a data portion, and the identifier and the copy control information are inserted in the header portion within the packet.

52. The method of claim 50, wherein the identifier and the copy control information are both transmitted in front of the digital content.

53. The method of claim 50, further comprising:

the digital content is encrypted before the transmitting step, and then the encrypted digital content, the identifier, and the copy control information are transmitted.

54. An apparatus for processing digital data, comprising:

a detecting unit for detecting an identifier indicating whether or not copy control information is included so as to identify the presence of the copy control information, which is necessary for determining whether or not copying of the digital data is permitted; and

and a controller for controlling the copy prevention function based on a state of the copy control information.

55. The apparatus of claim 54, wherein the copy protection function comprises encrypting or decrypting digital data.

56. The apparatus of claim 54, wherein the controller controls the copy prevention function such that the digital data is recorded on the recording medium only when the copy control information indicates that at least one copy is permitted.

57. The apparatus of claim 56, wherein the copy control information is updated to indicate that the copy is made when the digital data is recorded on the recording medium.

58. An apparatus for processing digital data, comprising:

a transmission section for transmitting the digital data, an identifier indicating whether or not copy control information is included so as to identify the presence of the copy control information, and copy control information necessary for determining whether or not to allow copying of the digital data;

an interface for transmitting and/or receiving digital data, an identifier and copy control information; and

a receiving section for receiving the digital data, the identifier and the copy control information through the interface,

wherein the receiving means comprises:

a detection unit for detecting the identifier and the copy control information from the transmitted digital data, an

A controller for controlling the copy prevention function based on the detected state of the copy control information.

59. The apparatus of claim 58, wherein the copy protection function comprises encrypting or decrypting digital data.

60. The apparatus of claim 59, wherein the controller controls the copy prevention function such that the digital data is recorded on the recording medium when the copy control information indicates that at least one copy is permitted.

61. The apparatus of claim 60, wherein the copy control information is updated to indicate that the copy is made when the digital data is recorded on the recording medium.