MXPA97009578A - Method and apparatus for the protection against copy in different means of registration, using unahuella de vi - Google Patents

Abstract

The present invention relates to a method for providing copy protection for program distribution means, comprising the steps of: adding an authentication signature to a track portion of the medium to be protected against copies; add a fingerprint signal to the program data, encode the program data with the fingerprint, record this encoded data in the medium, detect the authentication signature in a media player, detect the encoded data recorded from the medium, decode the encoded data detected, detect the fingerprint signal, enter the decoded data to an output device when the authentication signal and the fingerprint signal are detected, and enter decoded data to the data output device when the signal to strike is not detected

Description

METHOD AND APPARATUS FOR THE PROTECTION AGAINST COPY IN DIFFERENT MEANS OF REGISTRATION. USING A VIDEO FOOTPRINT REFERENCE WITH RELATED REQUESTS This application is a partial continuation of the application with Serial No. 08 / 267,635 ('635), filed on June 29, 1994, entitled "METHOD AND APPARATUS FOR COPY PROTECTION FOR VARIOUS RECORDING MEDIA" by John O Ryan. This application is also a partial continuation of the application with Serial No. 08 / 294,983 ('983), filed on August 24, 1994, entitled "A Video Finger Print Method and Apparatus".

BACKGROUND The optical compact disc (CD) is universally recognized as a supreme means of storing digital data. Its high packing density, its low manufacturing cost, and its relative immunity to poor handling can not be compared with other means. The success of the compact disc as a high-fidelity audio carrier is likely to be repeated in the Multimedia realm, where the technology has been adapted for the broader task of storing digitized audio, video, and alphanumeric information for a variety of purposes, which are satisfied with a plethora of standards such as DVD, CD-ROM, CD-Video, CD-I, and so on. To date, the copyright owners of the CD-ROM software have not had to contend with the imminent piracy (unauthorized copying) that afflicts the media of video cartridges and audio cartridges. This is almost entirely due to the large capital investment costs associated with performing replica masters and CDs, which creates substantial financial barriers to piracy. However, compact disc recording machines capable of making perfect copies of the data from CDs previously recorded for professional users for approximately two thousand dollars are now available, and it is very likely that in many years, the data will be widely available. reproductive-recorders that can be covered by the consumer. This will create a serious conflict between the needs of software products to sell their product for $ 50 +, to have profits, and the resulting ability of consumers to make a perfect copy for the price of a blank disk, projected early in the range from $ 10 to $ 20. It is possible that the problem is much more severe than the piracy that afflicts the video business, because, although few people want to watch a movie more than once, many multimedia software is intended to be used repeatedly, so that it is possible that the rule is property rather than rent. The fundamental problem solved by this invention, is to ensure that consumers can only enjoy products from the software manufacturer, by reproducing legitimately manufactured CDs. An approach to this problem of piracy, would be the inclusion of circuits against special copies inside CD recorders, bound by a general agreement between the manufacturers, similar to the System of Handling of Copies in Series (SCMS) developed for the medium of digital audio tape (DAT). With this scheme, the compact disc recorder would look for a special instruction of prohibition of copy in the digital data, and when finding it, it would stop the recording,. However, this system offers very limited protection. Even when the SCMS system was first proposed for the DAT environment, it was fully appreciated that it presented little protection from professional pirates or even amateurs, who, knowing the format of the data, could, and subsequently did, build "black boxes" (electronic circuits) to remove the copy prohibition instruction, thus making it possible for the recorders to make unlimited copies. Applicants believe that all systems against copies that rely on instructions that prohibit copies inserted in the data stream, they can be canceled by black boxes of the same order of complexity and cost as those of the circuits that are inside the compact disc recorders that look for these instructions. Therefore, these systems are of limited effectiveness. The black box would connect online between the compact disc player and a compact disc recorder, and would look for special instructions to prohibit copies in the data stream, and would simply re or modify these instructions. Therefore, it should be expected that if this kind of systems were adopted against copies, economic black boxes would proliferate. An additional difficulty with this approach to copy protection is the need to ensure that all manufacturers of compact discs include the necessary detection circuits in their products. Some manufacturers may not comply, perhaps in the expectation of increasing their market share. The presence of even a small percentage of machines that do not comply in the market could damage the viability of this type of copy protection scheme. For the above reasons, there is a need for a copy protection system for compact disc media that provides a high level of protection to software rights owners, that is immune to black boxes, and that is not compromised by the refusal of a few hardware manufacturers to comply with the standard.

SUMMARY OF THE INVENTION In accordance with the invention, a Conditional Reproduction System provides copyright protection for material previously registered in different media, for example compact disc media or Digital Video Discs. Since the invention to be described is applicable to many different media, and one skilled in the art could easily adapt the teachings of this invention to other media, the following description will describe its application to the Digital Video Disc (DVD) medium. , a version of the medium of compact discs. The invention overcomes the drawbacks of the system described above. The Conditional Playback System does not try to prevent DVD recorders from copying data from protected DVDs. Instead, it is a method by which DVD players can determine whether a particular DVD is a legitimate original or an illicit copy. If it is legitimate, the player plays the DVD normally. If it is not, the player is disabled, and may display an appropriate copyright warning message. During the manufacturing of the master disk, an Authentication Signature is printed on the disk, in a way that can not be read by a normal optical DVD player, but can be easily detected by other means. The nature of this Authentication Signature is such that it is faithfully transferred to all production discs made from this master. However, if an illicit copy of a production disc is made using a DVD recorder, the copy may contain a faithful replica of the disc's program data, but the Authentication Signature is not transferred to the Copy. All DVD players that conform to this copy protection standard would include a subsystem to search for the Authentication Signature. If the signature is not found, the DVD player will not play the disc. For CD applications, such as the DVD, the Preference Authentication Signature is printed on the master disk by modulating the radial position of the writing head that creates the master disk by a few tens of nanometers peak to peak around the normal position of the head. Then you can read this Authentication Signature in the DVD player with a minimum increase in the complexity of the player, taking advantage of the existing radial tracking servo system in the player, as will be described now. In all DVD players, the optical reading head is kept on the track by a sophisticated error detection system, as a normal part of the reproductive function. For example, if the head moves slightly to either side of the track, or the track moves from under the head due to an out-of-phase central spindle, an error is detected, and after amplification, it is applied to the actuator radial to re-center the head of the track. Since the optical read head must also track a radially induced position-modulation in a deliberate manner that defines an Authentication Signature, therefore, this error voltage contains a signal component corresponding to this, along with other corresponding signals. to elliptical and similar errors. Accordingly, by proper processing of this error voltage, the Authentication Signature can be detected.

The position-modulation signal can be a simple frequency sinusoidal, so that an integral number of cycles is printed during each revolution of the disk, or that a full cycle is printed during an integral number of revolutions of the disk. In any case, the extraction of the Authentication Signature from the different other tracking error signals is simplified. A relevant point of abnormal exploration is described in the Patent of the United States of America Number 5, 247,507 by Morimoto (incorporated by reference), which describes a fluctuation of the normal tracking signal, which causes the tracking to wander on a sinusoidal path around a main frequency. Clearly, this copy protection system can not be compromised by any external black box connected between a signal output from the DVD player and a signal input from the DVD recorder, since the Authentication Signature is not transferred to the tape recorder. Nor does the system compromise if a few manufacturers choose not to build the authentication system on their DVD players, because pirated record manufacturers would have to label their products as being able to reproduce only on the limited set of DVD players that do not. comply, which are in the market. The manufacturer of pirated discs, in effect, would be advertising the illegality of their product, and inviting prosecution. In the present three forms of these Systems of Conditional Reproduction are described. A common element of the three Conditional Reproduction Systems is the use of the special Authentication Signature described above, which is printed on legitimately manufactured DVDs, or in other media, in such a way that this Authentication Signature is not part of the sign of the registered "program", and therefore, it is not passed on to an illicit copy. The first of these Conditional Playback Systems, requires that all DVD players that conform to the particular standard in question - DVD, for example - should look for the Authentication Signature on each individual DVD that is going to be played. The control system of the DVD player would be designed to stop the reproduction of the DVD if the Authentication Signature was missing. As mentioned above, since an illicit copy of a DVD would not have the Authentication Signature, in effect, these copies would be useless. Accordingly, effective copy protection is performed, even when the illicit copy may contain a perfect replica of the program information.

The drawback of this first system, is that all legitimate DVDs that are intended to be played on these special DVD players, must have an Authentication Signature added. Therefore, this system is only suitable for closed systems, where a system controller can order that all DVDs be protected against copying. However, it is desirable, from a marketing point of view, to be able to offer and load copy protection on a program-by-program basis. The second and third Conditional Reproduction Systems that will be described later, have this capability. In a second Conditional Reproduction System, the DVDs that will be protected against copies, would contain a special instruction to tell all the DVD players that look for the Authentication Signature, and that they do not reproduce the DVDs in the absence of it. The instruction could be recorded, for example, in the initialization section of the DVD - the part normally reserved for non-program information. It would act on the instruction by means of a special subsystem in all the DVD players that comply. As a result, only copy-protected originals of DVDs could be reproduced - illicit copies would be rejected. This instruction would be omitted from DVDs of programs that do not require copy protection, and for those programs, both the original DVDs and their copies would be played normally. In this way, protection against copying could be offered on a program-by-program basis, through the use or non-use of this "Search for an Authentication and Play Only if Found" instruction. However, although this second Conditional Reproduction System allows the copy protection feature to be offered on a program-by-program basis, in principle it could be compromised by the special black boxes connected in the signal line between the reproducer of DVD and the DVD burner. These black boxes would look for this "Search ..." instruction in the data stream from the DVD player, and would remove or modify it, so that the resulting illicit copy would not trigger the authentication procedure on the DVD players. . A third System of Conditional Reproduction, called the Programmable Conditional Reproduction System (PCPS), overcomes the disadvantages of the systems described above, and provides a copy protection scheme that can be activated on a program-by-program basis, and that also It is highly resistant to the attack of the black box. This was fully described in the '983 application. The concepts of the application '983 are applicable to a system where only licensed manufacturers, called legitimate, could actually make discs. The state of the system is based on the need to cryptically encode the data that goes to the disk under a public cryptic encoding and the private key. These keys have to be kept in each legitimate manufacturer of the master disk. If someone is trying to protect a consumer, the recordable device that one has must be able to make discs to be played on their own machines for their own use. With this in mind, the system described above would lack the security required once you start giving the keys to everyone. Therefore, the value of the above is supported by a closed system. Since a user does not want anyone else to make discs to play on these machines, it is not advisable to have an open format. In the event that someone made a universal disk recording, it would happen that it can be played on these machines, then the purpose of this system would be voided. However, most of the new Digital Video Disc (DVD) formats that are being discussed, are more open formats, in such a way that no one should be able to make the discs play in the players. It is anticipated that the next generation of digital formats will be to have a product recorded by the consumer within 5 years. Consumers will be able to use it as they currently use their VHS machines. Accordingly, any system that requires data to be extended under only a secret key as necessary is less desirable. A slightly different approach called the Conditional Trace Reproduction System is needed. To overcome the deficiencies of a closed system, you need to add an indicator in the video system, telling the player that you are going to play a disc only if you see a fluctuating track, or play the disc unconditionally. This signal can not be easy to remove. This indication would replace the cryptic encoding / decoding system described in application 08 / 267,635. One method to perform this indication is to add a video footprint signal to the input video at a low level. A similar video fingerprint system is described in the '983 application, filed on August 24, 1994, entitled "A Video Finger Print Method and Apparatus" by Gregory Copeland. The important elements of this video footprint are: 1) a low visibility in the video signal, 2) a detection facility, and 3) difficulty of derivation effect. One can not just add a bit in the vertical blank space because it is easily removed. In a video signal, the viewer can tolerate a certain amount of noise or error. The fingerprint system, as described in the '983 application, adds a small amount of low-level survey that can not be seen, but can be reliably extracted. With this footprint system, the goals mentioned above can be achieved. In the case of digital data, a bit or a single error in one bit can destroy a complete computer program. The destruction can be anything from minor to catastrophic. In the video, you can have many errors in the signal, as long as the net image is perfectly fine, and this does not happen. The video footprint is easy to remove within the video domain. Even, it is relatively easy to be removed in the digital video domain, but it is very difficult to be removed in the MPEG domain. The most relevant digital video systems will use one or more versions of the Group of Images in Motion (MPEG) format. These formats involve video compression techniques for more efficient data transfer. There is no way to see the MPEG data and locate something. MPEG is not a linear system. Therefore, there is nothing that you can point to in the MPEG data that tells you that the video is getting up or is not getting up. A pirate would have to decode the MPEG signal to the baseband video. At this point, the fingerprint could be removed, but now the pirate has to re-encode the MPEG to make his disk. Coding is a major operation. It is not trivial. This is not a foolproof system, if someone has access to an MPEG encoder. This device costs hundreds of moles of dollars. To increase the video footprint, add a Video Footprint signal to the video before MPEG encoding. The video footprint signal is implemented by adding a small amount of survey to field 1, approximately 1 millivolt to field 1, and subtracting 1 millivolt from the survey from field 2. This would be done all the time through the film or another video recording. The receiving device would continuously store field 1 and then subtract it from field 2. Because two opposites are being subtracted, the Video Footprint Signals would be added, and the video signal would be subtracted. The result is integrated over a period of time, and a few seconds will suffice. A voltage that can be detected will accumulate. The player detects this signal after decoding MPEG. If the signal is present, the player knows that the disk is a copy protected disk. The player will search if the track is fluctuating by seeing the servo signal. The indication detected in the video system tells the player to play a disc only if an Authentication Token. If a Video Footprint Signal is not detected, the player will not look for an Authentication Signal, and will reproduce unconditionally. The above description is based on the premise that the disc would be carrying a video signal. Many digital video discs can be used for computer data, due to its large data handling capacity. However, it is possible that in the vast majority of applications, the computer program also involves video. The following description describes a modality of the Conditional Playback System in a DVD system.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a block diagram of the hardware of the master realization process, which incorporates some elements of the invention. Figure 2 is a block diagram of the compact disk reproduction device incorporating other elements of the invention.

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for protecting against different copies of program distribution means, such as the Digital Video Disc (DVD). This invention is applicable to all disc media, and the principles may be extended by one of ordinary skill in the art to other media, such as magnetic tape. The invention offers a high level of protection to owners of software rights, is immune to black boxes, and will not be compromised by the refusal of a few hardware manufacturers to comply with the standard. As mentioned above, it is desirable to be able to offer copy protection to copyright holders on a program-by-program basis, and receive a fee per program or a per-disc fee in exchange. This is done in a Conditional Footprint Reproduction System (FPCPS) that uses a combination of a video footprint system and an authentication signal to allow the DVD player to handle either copy-protected disks or non-copy-protected discs. , in a way that is difficult or prohibitively expensive and time consuming to commit, using black boxes. One mode of the FPCPS covers a device for making a master disk as in the Figure, and another portion in a DVD player, as in Figure 2. The FPCPS Master Disk Realization installation includes a protection recording device. against copies 10 which accepts a video signal from the conventional source, the input terminal 22, which is inserted into the Video Footprint Inserter 12. This conventional video source can be in a 525/60 format or in a 625 / format fifty. Additionally, Video Footprint Inserter 12 receives the Copyright Material Command Signal 22 from Switch 20, to insert a Video Footprint Signal into the video signal before MPEG encoding. The Video Footprint Signal is implemented by adding a small amount of survey to field 1, approximately 1 millivolt, and subtracting an i-volt of the survey from field 2. This alternating field insertion is done all the time through the movie or another video recording. The Video Footprint Inserter would insert the video fingerprint signal only when Switch 20 is in the Copyright Protection position, as shown in Figure 1. When Switch 20 is in the No Rights Protection position of Author, a video footprint insert does not take place. The output of the Video Footprint Inserter 12 is coupled with the MPEG Encoder 14. The MPEG Encoder 14 converts the conventional video signal with or without a video fingerprint signal to a signal in MPEG format. The output of the MPEG Encoder 14 is coupled to the Master Disk Device, to make master discs. The Switch 20 is also coupled with an Authentication Signature Generator input 24. The Authentication Signature Generator 24 generates an Authentication Signature 18, the nature and purposes of which were described above. Line 18 connects the Output Authentication Signature Generator 24, with the radial actuator inside the master disk system (not shown), only when the Copyright Protection mode is selected by Switch 20. The protection apparatus counterpart 30 copies, contained within the DVD player, is shown in Figure 2. The MPEG program data from the DVD on line 32, appropriately decoded and corrected for error, is input to the MPEG 36 Decoder, the which converts the MPEG program data into a video signal that may or may not include a video fingerprint signal. The output MPEG 36 Decoder is coupled to an input of the Switch 40, and to an input of the Video Footprint Detector 48. The Video Footprint Detector 48 continuously stores the field 1, and then subtracts it from the field 2 of each framework. The Video Footprint Detector 48 is subtracting two opposing video fingerprint signals, the sum of the video fingerprint signals, and the subtraction of the video signal. The Video Footprint Detector 48 integrates the result for a period of time, and a few seconds will suffice. A voltage build-up that can be detected is developed. If the Video Footprint Signal is present, the player knows that the disc contains copyrighted material. The output of the Video Footprint Detector generates a Copy Protection Signal 52, which is coupled to a first input of an AND (Y) 54 Gate. The error signal from the radio tracking servo amplifier of the DVD on line 34, it enters the Authentication Signal Detector 38. As explained above, this signal will have a component corresponding to the Authentication Signature. The Authentication Signature Detector 38 is designed to generate a binary output on line 50 corresponding to the presence or absence of the Authentication Signature at its input. For example, this output can be logical 1 in the presence of the Authentication Signature, and a logical 0 in its absence. The logic levels are selected to cause the AND (Y) gate 54 to cause an output when the Authentication Signature is detected. Gate AND (Y) 54 produces a signal 56 to Gate OR (or) 58, when both the video fingerprint signal and the Authentication Signature are detected. The second input to Gate OR (or) 58, is produced from the Video Footprint Detector, only when the video footprint is not selected. The output of the OR gate (or) 58, is coupled with the selector of the Switch 40, to connect the output of the MPEG Decoder with the Video and Audio Output System, only when both the Video Footprint Signal and the Authentication Signing Signs, or when the Video Footprint Signal is present. Now we can appreciate the operation of this System of Conditional Reproduction of Footprint, by examining its response under different circumstances. • When playing an original copy-protected or non-copy-protected disc, the presence or absence of the Video Footprint Signal causes the Switch 40 to correctly select the Decoded Video in MPEG. As a result, all the original discs will play normally. • When playing a copy of a non-copy protected disc, the absence of the Video Footprint also causes the S switch to correctly select the Decoded Video in MPEG, again allowing these discs to play normally. • However, when an illicit copy of a copy protected disc is reproduced, the absence of the Authentication Signature causes the S switch to not correctly select the Decoded Video Signal in MPEG. The security of the Video Footprint makes it very difficult or inexpensive for a pirate to make reproducible copies of protected discs. To make reproducible copies of copy-protected discs, that is, to override this scheme, a pirate must do one of the following: 1. detect and remove the Footprint signal.

Video. 2. Re-encode the video signal into an MPEG signal. As discussed earlier, this is very expensive. 3. Add a viable Authentication Signature to the illicit copies, as the discs are recorded, in such a way that the reproducing DVD players reproduce these discs normally. This is possible, but to do so, the pirate needs to make major modifications to a DVD recorder to make it possible to extend the tracks modulated in the radial position. These modifications are beyond the capabilities of consumers and software merchants. However, it is unrealistic to insist that a well-financed pirate operation could not find a way to do it. There are different ways to make it harder for a pirate to "forge" an Authentication Signature, but all of these depend to a greater or lesser degree on the exact capabilities of the radial servo system (if any) on the available DVD recorders. For example, the signature may be in the form of a pulse function (instead of a simple sinusoidal) in such a way that the radial servo of a commercially available DVD recorder can not track it. Of course, if we allow this mythical pirate unlimited financial resources, he could invest in a professional master disc-making system, and make the necessary modifications. However, as a practical matter, the ability of this system and method to eliminate piracy at the level of the consumer, the distributor, and the professional with technical knowledge, should be extremely valuable. Although the above modalities have described a Conditional Playback System for DVD and other compact disc formats, the principles are also applicable to the magnetic tape format. For these applications, the Authentication Signature Signal could be added to the tape control track. Although the invention has been described in relation to the preferred embodiments, it will be appreciated by those skilled in the art that different changes can be made without departing from its spirit. If the coverage provided by the applicants is defined by the claims and their equivalents.

Claims (10)

NOVELTY OF THE INVENTION Having described the above invention, it is considered as a novelty, and therefore, the content of the following is claimed as property: CLAIMS

1. A method for providing copy protection for program distribution means, which comprises adding an authentication signature to a tracking portion of the medium to be protected against copies, entering program data (22), adding a footprint signal (12) to the program data, coding the program data with the fingerprint (14), registering this encoded data in the medium (16), detecting the authentication signature in a middle reproducer (38), detecting the encoded data recorded from the medium, and decoding the detected encoded data (32), detect the fingerprint signal (48), characterized in that the input of the decoded data to a data output device (42) is only realized when the signal is detected of authentication (50) and the fingerprint signal (48), or when the fingerprint signal (48) is not detected.

2. A method according to claim 1, characterized in that the program data comprises a video signal.

3. A method according to claim 2, characterized in that the footprint signal comprises a small additional survey on the video signal on a first field, and a smaller low survey on a second field during multiple frames of the video signal.

4. A copy protection system for a program distribution means comprising an element for adding an authentication signature to a track portion of this medium, for protection against copies, a means for entering program data (2), means for adding a fingerprint signal to the program data (12), a means for coding the program data with footprint (14), means for recording this data encoded in the medium (16), a means for detecting the signature of authentication in a media player (38), a means for detecting the encoded data recorded from the medium, a means for decoding the detected encoded data (36), and a means for detecting the trace signal (48), characterized in that the decoded data is put into a data output device when the authentication signal (50) and the fingerprint signal (48) are detected, or when the fingerprint signal is not detected.

5. A reproduction apparatus for protecting against copies of a program distribution means, which comprises a first detector for detecting an authentication signature from a track portion of the medium (38), a second detector for detecting the encoded data registered from the middle, a decoder for decoding this detected coded data (36), a third detector for detecting the presence of the fingerprint signal within the decoded data, a fourth detector for detecting the presence of the authentication signature and the fingerprint , or the absence of the fingerprint signal (54), characterized in that a selector controlled by the fourth detector allows an output of the decoded data medium, to put the decoded data into a data output device, when both the signature is detected of authentication such as the fingerprint, or when the absence of the fingerprint is detected.

6. A method for providing protection against copying in a master making process of a recording medium, which comprises the steps of inserting a data stream, inserting a fingerprint signal into this data stream (12), coding the data stream with fingerprint (14), and generating an authentication signature signal, characterized in that the fingerprint data stream is recorded in the recording medium, and the authentication signature signal is coupled with a control mechanism with time base of a recording device, to modify the time base control mechanism according to an authentication signature signal.

7. A method according to claim 6, characterized in that the recording medium is an optical compact disc.

8. A method according to claim 6, characterized in that the recording medium is a DVD disc.

9. A method according to claim 6, characterized in that the recording medium is a magnetic tape.

10. A method according to claim 6, characterized in that the data stream is a video signal.