EP1287695A1 - Procede empechant la copie de donnees numeriques - Google Patents

Procede empechant la copie de donnees numeriques

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Publication number
EP1287695A1
EP1287695A1 EP00962711A EP00962711A EP1287695A1 EP 1287695 A1 EP1287695 A1 EP 1287695A1 EP 00962711 A EP00962711 A EP 00962711A EP 00962711 A EP00962711 A EP 00962711A EP 1287695 A1 EP1287695 A1 EP 1287695A1
Authority
EP
European Patent Office
Prior art keywords
data
data stream
identification information
identification code
identification
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP00962711A
Other languages
German (de)
English (en)
Inventor
Mark Thomas On-Digital plc BARRINGTON
Andrew Jim Kelley Headley Lodge GLASSPOOL
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ITV Digital PLC
Original Assignee
ITV Digital PLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ITV Digital PLC filed Critical ITV Digital PLC
Publication of EP1287695A1 publication Critical patent/EP1287695A1/fr
Withdrawn legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/45—Management operations performed by the client for facilitating the reception of or the interaction with the content or administrating data related to the end-user or to the client device itself, e.g. learning user preferences for recommending movies, resolving scheduling conflicts
    • H04N21/462—Content or additional data management, e.g. creating a master electronic program guide from data received from the Internet and a Head-end, controlling the complexity of a video stream by scaling the resolution or bit-rate based on the client capabilities
    • H04N21/4627—Rights management associated to the content
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/41—Structure of client; Structure of client peripherals
    • H04N21/4104—Peripherals receiving signals from specially adapted client devices
    • H04N21/4135—Peripherals receiving signals from specially adapted client devices external recorder
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/41—Structure of client; Structure of client peripherals
    • H04N21/418—External card to be used in combination with the client device, e.g. for conditional access
    • H04N21/4181—External card to be used in combination with the client device, e.g. for conditional access for conditional access
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
    • H04N21/44—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream or rendering scenes according to encoded video stream scene graphs
    • H04N21/4408—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream or rendering scenes according to encoded video stream scene graphs involving video stream encryption, e.g. re-encrypting a decrypted video stream for redistribution in a home network
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
    • H04N21/442—Monitoring of processes or resources, e.g. detecting the failure of a recording device, monitoring the downstream bandwidth, the number of times a movie has been viewed, the storage space available from the internal hard disk
    • H04N21/44204—Monitoring of content usage, e.g. the number of times a movie has been viewed, copied or the amount which has been watched
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N7/00—Television systems
    • H04N7/24—Systems for the transmission of television signals using pulse code modulation
    • H04N7/52—Systems for transmission of a pulse code modulated video signal with one or more other pulse code modulated signals, e.g. an audio signal or a synchronizing signal

Definitions

  • the present invention relates to digital video broadcasting, in particular broadcasting compliant with the DVB standards as issued by ETSI which themselves cite the MPEG Video Standard: ISO/IEC 13818-2: Information technology - generic coding of moving pictures and associated audio information: Video (1996) (a a ITU-T Rec. H-262 (1996)) (hereinafter referred to as the MPEG-2 standard) .
  • the present invention also relates to broadcasting to a population of receivers compliant with the DVB standard EN50221 : 1997.
  • a known method employs scrambling or encryption of the data content of one or more of the data streams of a programme for which access is to be restricted.
  • an interface definition is included in the standard to enable provision of corresponding descra bling in a module known as a controlled access module, where this module is separate from a host apparatus .
  • the present invention advantageously provides a form of copy protection that is applicable to arrangements such as DVB.
  • the form of copy protection provided can operate independently of the existing descrambling procedure provided for example by the DVB standards.
  • the form of copy protection provided by the present invention can be employed to effectively avoid the existence of an in the clear signal between a controlled access module and a host apparatus without necessarily having to have a device within the host apparatus to enable reading of copy protected programmes .
  • the present invention provides a digital broadcast system which enables real time viewing but inhibits copying of the broadcasts by including misinformation in the broadcast.
  • the present invention provides apparatus for generating a digital data stream for transmission wherein information indicating the location in the data stream of a particular broadcast or a part of a broadcast (for example a video or audio data stream or portion thereof) is deliberately corrupted or falsified.
  • the present invention also provides a digital data stream generated by apparatus in accordance with the second aspect.
  • the present invention provides apparatus for extracting a broadcast from a digital data stream generated by apparatus in accordance with the second aspect despite the deliberate corruption or falsification of location information by using previously provided information or information provided with the digital data stream in, for example, an encrypted or scrambled form.
  • Figure 1 is a schematic illustration of a broadcasting arrangement in accordance with the present invention.
  • Figure 2 schematically illustrates the components of a broadcast system of an embodiment of the invention
  • Figure 3 illustrates functionally a broadcast processor of an embodiment of the invention
  • Figure 4 illustrates a portion of a multiplex stream of data employed in an embodiment of the invention
  • Figure 5 shows the processing operations performed by a broadcast processor in an embodiment of the invention
  • Figure 6A shows a multiplexed data stream provided in an embodiment of the invention
  • Figure 6B schematically illustrates PAT and PMT tables employed in an embodiment of the invention
  • Figure 7 shows the processing steps performed in the generation of PSI information tables in an embodiment of the invention
  • Figure 8 schematically illustrates functionally a receiver employed in an embodiment of the invention
  • Figure 9 shows the processing steps employed in the operation of a demultiplexer under the control of a microprocessor in an embodiment of the invention
  • Figure 10 shows a schematic functional diagram illustrating one example of a receiver in combination with a video recorder employed in an embodiment of the invention
  • Figure 11 shows a schematic functional block diagram illustrating another example of a receiver in combination with a video recorder.
  • FIG 1 schematically illustrates a broadcasting arrangement according to the present embodiment.
  • Broadcaster 2 broadcasts television programmes which in the present embodiment are received by receivers 4 , 6 and 8 via transmission links 10, 12 and 14 respectively.
  • Broadcaster 2 broadcasts the television programmes in the format defined by the DVB standards.
  • Receivers 4, 6 and 8 are similarly compliant with the DVB standards including EN50221.1997. Although only three receivers 4, 6 , 8 are shown in Figure 1 , in practice many more receivers will be arranged to receive broadcasts from broadcaster 2.
  • Various forms of transmission link are employed by broadcaster 2 in the present embodiment. In the case of those shown in Figure 1, transmission link 10 represents terrestrial broadcast, transmission link 12 represents satellite broadcast and transmission link 14 represents cable broadcast.
  • Broadcaster 2 includes an arrangement, shown in Figure 2, for integrating and transmitting a plurality of television programmes in a single broadcast.
  • the arrangement includes a broadcast processor 20 whose input is coupled to programme store 22 storing pre-recorded programmes and programme feed 26 for supplying live programmes.
  • a first television programme will be input into broadcast processor 20 from programme store 22, and a second television programme will be input into broadcast processor 20 from programme feed 26.
  • An output of broadcast processor 20 is coupled to transmitter 28.
  • Transmitter 28 is arranged to transmit broadcasts via transmission links 10, 12 and 14.
  • the programmes are supplied from programme store 22 and programme feed 26 in the form of elementary data streams.
  • programme 1 as provided by programme store 22 is formed from two elementary data streams, that is one video stream 32 and one audio stream 33.
  • television programme 2 as provided by programme feed 26 consists of a single video stream 34, and two audio streams 33 and 35.
  • Broadcast processor 20 includes PID processor 30, where PID refers to Packet Identification Code as employed in the MPEG-2 standard which itself is employed in the DVB standard.
  • PID processor 30 is arranged to receive the elementary data streams 32 to 36 described above.
  • PID processor 30 also includes a programme specific information (PSI) generator 38.
  • PSI programme specific information
  • PID processor 30 is coupled to packetiser 40 such as to forward the elementary data streams 32 to 36 and an output of PSI generator 38 to packetiser 40.
  • Packetiser 40 is coupled to multiplexer 42. An output of multiplexer 42 forms an output of broadcast processor 20 and is thus coupled to transmitter 28 as described earlier.
  • FIG. 4a shows a portion 50 of a multiplexed stream of such packets 52, 54 and 56.
  • Packets 52, 54 and 56 comprise respective headers 58,62 and 66 and respective payloads 60, 64, 68, each of the format defined in the MPEG-2 standard.
  • each header 58,62,66 is formed of the components shown in Figure 4b.
  • the part of the header shown as item 72 which carries the value of the PID.
  • the PID serves to identify the elementary data stream from which the payload of the particular packet was derived. As defined by the MPEG-2 standard, the PID consists of 13 bits, consequently its value can range from zero through to 8191.
  • Figure 5 shows the processing operations performed by broadcast processor 20 in this embodiment.
  • PID processor 30 identifies the source of each of the elementary data streams.
  • PID processor 30 allocates a respective PID value to each elementary data stream.
  • PSI information tables are generated, by PSI generator 38. In the present embodiment the PSI tables are of the form defined in the MPEG-2 standard.
  • PID value 20 is allocated to the single video stream of programme 1
  • PID value 30 is allocated to the single audio stream of programme 1
  • PID value 40 is allocated to the single video stream of programme 2
  • PID value 50 is allocated to audio stream 1 of programme 2
  • PID value 60 is allocated to audio stream 2 of programme 2.
  • each data stream is packetized by packetizer 40, and similarly the PSI tables are packetized by packetizer 40.
  • Each packet produced consists of a payload of 188 bits and a header containing the appropriate allocated PID value.
  • the packets are multiplexed into a single multiplexed data stream shown schematically in Figure 6A.
  • Figure 6A shows by way of example one packet for each of the PID values employed in the present embodiment.
  • packet 80 contains content from the single video stream of programme 1 and has PID value 20
  • packet 82 contains content from the single audio stream of programme 1 and has PID value 30
  • packet 84 contains content from the video stream 1 of programme 2 and has PID value 40
  • packet 86 contains content from audio stream 1 of programme 2 and has PID value 50
  • packet 88 contains content from audio stream 2 of programme 2 and has PID value 60
  • packet 90 contains the PMT for programme 1 and has PID value
  • packet 92 contains the PMT for programme 2 and has PID value 77
  • packet 94 contains the PAT and has PID value zero.
  • Step S15 in which the PSI generator generates the PSI information tables will now be described in more detail with reference to Figure 7.
  • the PAT is generated in a manner consistent with the MPEG-2 standard.
  • the correct PID values for each respective TV programme are inserted into the PAT, thus forming the PAT shown as item 100 in Figure 6B in which TV programme 1 is associated with PID value 25 and programme 2 is associated with PID value 77.
  • a PMT is prepared for the first television programme to be considered, which in the present case is programme 1.
  • Preparation of the PMT consists of listing each data stream that contains content of that television programme.
  • the list of data streams consists of a single video stream and a single audio stream.
  • the allocated PID values for these data streams are collected, i.e. PID value 20 for the video stream and PID value 30 for the audio stream.
  • the PSI generator determines whether the programme under consideration is to be copy protected. Such determination can be carried out dependent on a manual intervention by an operator, or can be based on criteria prestored in a memory of the PID processor 30. In the present example programme 1 is indeed to have copy protection applied thereto.
  • the collected PID values i.e. PID value of 20 for the video stream and PID value 30 for the audio stream, are adjusted. In the present embodiment each PID value is adjusted by having its value reduced by 1.
  • PID value 20 is adjusted to PID value 19, and PID value 30 is adjusted to PID value 29.
  • final PID values are determined as being equal to the adjusted PID values described immediately above.
  • the final PID values in this case PID value 19 for the single video stream and PID value 29 for the single audio stream, are inserted into the PMT for programme 1, forming the complete PMT for programme 1 which is as shown as item 96 in Figure 6B. It can be seen by comparing Figure 6B with Figure 6A that the PID values for the data streams of programme 1 in PMT 96 are different from the PID values actually allocated to the packets carrying those data streams as payloads.
  • programme 2 is still to be processed so the process returns to S40 where the PMT is prepared for programme 2.
  • the list of data streams consists of a single video stream plus audio stream 1 and audio stream 2 .
  • the allocated PID values for these data streams are collected, i.e. PID value 40 for the video stream and PID values 50 and 60 for audio streams 1 and 2 respectively.
  • step S50 it is determined in the present embodiment that programme 2 is not required to have copy protection. Consequently the process moves to step S65 where the final PID values are set equal to the allocated PID values, in other words no adjustment of PID values takes place.
  • the PID values inserted are 40, 50 and 60 respectively, providing correct correspondence to the PID values allocated to the actual packets as shown in Figure 6A. Since programme 2 is the last programme to be considered in the present example, at step S75 the process continues on to step S20 as shown in Figure 5 and described earlier.
  • Receiver 4 includes host apparatus 202, controlled or conditional access module 204 and display/loudspeaker apparatus 216.
  • Host apparatus 202 and controlled access module 204 both comply with the DVB and MPEG-2 standards.
  • the display/loudspeaker apparatus 216 will generally be integrated with the host apparatus 202 to form a digital television set.
  • Host apparatus 202 includes tuner 206 coupled to demodulator 208 which itself is coupled to output 209. Host apparatus 202 further includes input 210 coupled to demultiplexer 212 which itself is coupled to MPEG decoder 214. MPEG decoder 214 is coupled to an output which is connected to display/loudspeaker apparatus 216. Host apparatus 202 further includes microprocessor 211 which is coupled to demultiplexer 212 and is also coupled to input/output 213.
  • Controlled access module 204 includes de-scrambler 218 which is coupled to input 220 and output 222. Controlled access module 204 also includes microprocessor 224 which is coupled to input/output 226 of controlled access module 204. In the present arrangement output 209 of the host apparatus is connected to input 220 of the controlled access module, and output 222 of controlled access module 204 is connected to input 210 of host apparatus 202. These two connections form an interface which is defined in the DVB standards and termed the MPEG-2 transport stream interface. Input/output 213 of host apparatus 202 is coupled to input/output 226 of controlled access module 204. This latter connection forms a further logical interface which is defined in the DVB standards and called the command interface.
  • an RF broadcast signal is received by tuner 206.
  • Tuner 206 tunes to the appropriate RF frequency enabling it to forward the signal or channel, to demodulator 208.
  • Demodulator 208 demodulates the broadcast multiplexed data stream from the RF carrier frequency. The frequency to which the tuner is tuned will depend upon the digital channel selected by the user.
  • the demodulated multiplexed packet stream is passed from output 209 of host apparatus 202 to input 220 of controlled access module 204 and then to descrambler 218.
  • the programme contents within the respective video streams and audio streams have been scrambled in compliance with the DVB standards and in conventional fashion, for commercial reasons. It should be understood that this scrambling is separate to the additional copy protection selectively applied by adjusting PID-values in the present embodiment.
  • Descrambler 218 of controlled access module 204 descrambles the programme contents.
  • the data stream output from descrambler 218 consists of the packets described above with reference to Figure 6A.
  • This data stream is passed from output means 222 of controlled access module 204 via input means 210 of host apparatus 202 to demultiplexer 212 of host apparatus 202.
  • Demultiplexer 212 under control of microprocessor 211, demultiplexes the data stream using the PSI tables to extract a user-selected TV programme under instructions received from microprocessor 211.
  • the demultiplexer 212 will be unable to extract the copy-protected programme 1 simply by using the PMT 96 for programme 1 because the PID values in the PMT 96 for programme 1 are false and do not correspond to the actual PID values for that programme.
  • the microprocessor 224 Upon receipt of an input signal at input 220, the microprocessor 224 checks the time and date information which is transmitted in the multiplexed data stream and, provided this time and date information is not earlier than that of the microprocessor's internal clock and calendar, then the microprocessor 224 supplies signals across the command interface using a standard command, known as the tune command (which is defined in the DVB standards) to enable the microprocessor 221 to adjust the false PID values to the correct PID values.
  • the tune command which is defined in the DVB standards
  • the tune command can include such instructions for more than one initial PID value.
  • This tune command can conventionally be employed for the purpose of controlled access module 204 arranging for an alternative visual or audio output to be provided to the user when that user is not authorised to have the content of the originally selected programme descrambled by descrambler 218.
  • the PID values to which microprocessor 211 redirects the multiplexer 212 will conventionally lead to the display of some type of message explaining that the requested programme cannot be viewed.
  • the tune command is employed to enable microprocessor 211 to redirect the multiplexer 212 back to the correct PID values of the requested television programme.
  • data identifying the PID values for such redirection is required, and the PID values to which the multiplexer 212 must be redirected are stored in the memory associated with microprocessor 224 until the required adjustment, being determined by the protocol used by PSI generator 38 of PID processor 30 to generate PSI tables of the present embodiment.
  • microprocessor 211 of host apparatus 202 receives a programme selection from a user of host apparatus 202. Any conventional user interface means, for example push button controls or infrared remote control, can be employed.
  • microprocessor 211 requests the contents of packets with PID value equal to zero from demultiplexer 212. These packets will contain the information forming PAT table 100.
  • demultiplexer 212 supplies the corresponding packet contents to microprocessor 211 which therefore receives the information content of PAT table 100.
  • microprocessor 211 reads off the PID value corresponding to the selected programme.
  • the PID value read off is PID value 25.
  • microprocessor 211 requests demultiplexer 212 to extract packets with PID value equal to 25 in the header.
  • demultiplexer 212 duly extracts the packets with PID value 25, that is the packets whose contents constitute the PMT for programme 1 (shown as item 96 in Fig. 6B) and supplies these packets to microprocessor 211.
  • Microprocessor 211 now processes the PMT for programme 1 by reading off the PID values for the data streams that hold the content of programme 1.
  • microprocessor 211 reads off PID value 19 for the video stream and PID value 29 for the audio stream.
  • microprocessor 211 determines whether any of the read off PID values correspond to PID values for which retune commands have been received from microprocessor 224, as described earlier above.
  • the microprocessor 224 will have instructed the microprocessor 211 to adjust the PID values.
  • the tune command would have instructed microprocessor 211 to adjust any PID values 19 to an adjusted value of 20 and any PID values of 29 to an adjusted value of 30. Accordingly, at step S136 the read off PID values of 19 and 29 are adjusted to 20 and 30, respectively.
  • microprocessor 211 sets a parameter called the "decided PID value", equal to the adjusted PID values of 20 and 30 in the present case.
  • microprocessor 211 instructs demultiplexer 212 to extract packets with the decided PID values that have been established as above, which in the present case are PID value 20 and PID value 30.
  • demultiplexer 212 has been instructed to extract packets whose PID values are the correct values for extracting the contents of programme 1, thus correctly enabling access to the copy protected programme.
  • MPEG decoder 214 decodes the extracted packets and at S160 the display/loudspeaker apparatus 216 successfully presents the requested programme contents of programme 1.
  • programme 2 is a programme which has not been copy protected according to the method of the present invention, in other words it is a programme that is allowed to be included 'in the clear' when passed from descrambler 218 of controlled access module 204 to demultiplexer 212 of host apparatus 202.
  • programme 2 is selected by a user, the process already described for programme 1 with reference to Figure 9 is similarly followed, except that at step S132 it is determined that none of the read off PID values were included in the received tune commands. Consequently the process moves to step S144 where the parameter called "decided PID value" is simply set equal to the actual read off PID values.
  • programme 2 will be extracted from the multiplexed data stream and successfully presented by display/loudspeaker apparatus 216.
  • FIG 10 shows the receiver of Figure 8 coupled to a digital video recorder 242 to illustrate the effect of the copy-protection.
  • Digital video recorder 242 includes a microprocessor 252 coupled to an input/output 254, a recording means 260 and a playback means 270 coupled to an output 250.
  • Microprocessor 252 of the digital recorder 242 is coupled to the microprocessor 211 of the host apparatus 202 via input/output 254 of the digital video recorder 252 and a further input/output 230 of the host apparatus, this connection forming another example of the earlier described command interface compliant with the DVB standard.
  • Output 250 of the digital video recorder 242 is connected to an additional input 240 of the host apparatus 202.
  • Input 210 of the host apparatus is connected by switch SWl to the demultiplexer 212.
  • Input 240 is also directly connected to the demultiplexer 212.
  • Switch SWl is closed when the digital video recorder is not present but is otherwise open.
  • An output 241 of the host apparatus 202 is connected to the record means 260 through input 251 of the digital video recorder.
  • the input 251 and output 250 of the digital video recorder 242 are coupled by a switch SW2 which is open for playback and closed during recording or when the digital video recorder 242 is idle.
  • Controlled access module 204 and host apparatus 202 function as previously described except that the output 222 of the controlled access module is coupled to the demultiplexer 212 via input 251, switch SW2 and output 250 of the digital video recorder 242 and input 240 of the host apparatus rather than directly through input 210 of the host apparatus.
  • the copy protected television programme can be presented successfully for viewing directly in real time, that is at the time the programme is broadcast.
  • the digital video recorder 242 records the whole multiplexed data stream.
  • the signal output by the playback means 270 is supplied directly to the demultiplexer 212 via the input 240.
  • the microprocessor 226 does not supply instructions over the command interface to the microprocessor 221 to adjust any false PID values.
  • the demultiplexer 212 selects the false PID values and is not able to extract the required packets from the received multiplex data stream.
  • the demultiplexed signal supplied to the MPEG encoder 214 is incorrect and the display/loudspeaker apparatus 216 does not present the required programme despite the fact that this content was recorded by the digital video recorder 242.
  • the owner of the equipment shown in Figure 10 cannot record copy protected programmes for later viewing. This enables the broadcasters and suppliers of the broadcast to restrict or inhibit recording of certain programmes whilst still allowing immediate viewing of those programmes. This is of particular interest for, for example, the broadcast of recently released films or movies.
  • the digital video recorder 242 records the entire multiplexed data stream.
  • the digital video recorder may be provided with its own demultiplexer and MPEG decoder to enable an operator of the video recorder to select a particular programme for recording (which may be different from a programme being presented in real time on the display/loudspeaker apparatus 216). It will, however, be appreciated that because the digital video recorder 242 does not receive any instructions from the microprocessor 226 of the controlled access module to adjust any false PID values, the digital video recorder will not be able to compensate for any false PID values and accordingly will not be able to copy any programme carrying the copy protection described above.
  • Figure 11 shows a schematic functional block diagram similar to Figure 10 in which the positions of the digital video recorder 242 and controlled access module have been switched so that the microprocessor 252 of the digital video recorder is connected to the input/output 213, the record means 260 of the digital video recorder is connected to the output 209 of the host apparatus, the output 250 from the playback means 270 of the digital video recorder 242 is connected to the descrambler 218 of the controlled access module 204 via input 210 and output 241 of the host apparatus 202 and input 220 of the controlled access module 204.
  • the descrambler 218 is connected via output 222 to the input 240 and then the demultiplexer 212 of the host apparatus.
  • switch SWl is closed when the controlled access module is not present but is otherwise open.
  • Switch SW2 is open only during playback by the digital video recorder.
  • the controlled access module 204 cannot tell whether the signal received on input 220 comes directly from the demodulator 208 or is being received from the playback means 270 and that therefore it would not be possible for the controlled access module 204 to determine whether the signal being received is a real-time broadcast or a recorded signal.
  • the multiplexed data stream includes time and date information in a TDTSI signal which is transmitted periodically in the multiplexed transport stream and may also include time and date information in the proprietary data stream.
  • the time and date information in the signal will only match its own or be later than its own if the signal at the input 220 is a real-time broadcast signal received directly from the demodulator 208 via the closed switch SW2. If the signal received at the input 220 is a recorded signal from the playback means 270, then the time and date information in the received signal will relate to an earlier time and possibly also an earlier date. When the microprocessor 226 determines that the time and date information in the signal received at input 220 is earlier than its own time and date information, then the microprocessor 226 will not send instructions over the command interface to the microprocessor 211 to enable any false PID values to be adjusted.
  • the demultiplexer 212 will not be able to extract the required packets from the received multiplexed recorded data stream and hence the signal supplied to the MPEG decoder 214 will be incorrect and the display/loudspeaker apparatus 216 will not present the required programme.
  • Persons authorised by the broadcaster to make copies may be provided with a digital video recorder in which microprocessor 252 is equipped with suitable compensation information, thereby enabling microprocessor 252 to initiate PID-value adjustment. This enables recording of the data streams of television programme 1.
  • programme 2 and any other programmes can be similarly copy protected if required.
  • copy protection can be applied to other types of data streams in addition to video and audio, for example text data streams.
  • the PID values as contained within a PMT were adjusted and effectively rendered false.
  • one or more PID values within a PAT are varied instead of PID values in a PMT.
  • PID values from both one or more PMTs and the PAT are adjusted.
  • the number of PID values changed in each table may be one or more than one.
  • each PID value to be changed was changed in a systematic fashion consisting of reducing its value by one e.g. PID value 20 was changed to PID value 19. It is to be appreciated however that the present invention is not limited to this specific alteration.
  • the PID value can be reduced by an amount greater than one, alternatively it can be increased by a specific value of one or more, or different PID values can be changed by different amounts.
  • any specific PID value can be varied by different amounts as a function of time.
  • the amount by which a PID value is changed is varied whenever a new television programme starts, or at advertisement breaks between programmes, and so on.
  • the amount by which PID values are to be changed can vary according to predetermined periods of time, e.g. every 30 minutes.
  • algorithms are employed to provide a more complicated function by which PID value variation amounts themselves vary over time or in response to certain events and inputs.
  • any of the above ways of adjusting PID values to provide copy protection can be applied intermittently, thus alternating with in the clear transmission. This would mean that access to a particular programme was only intermittently copy protected, however, that can sometimes be sufficient to fulfil the commercial or other reasons underlying the intention to copy protect a specific program.
  • microprocessor 224 is pre-programmed with the algorithms or information necessary to achieve the required compensation.
  • microprocessor 211 of host apparatus 202 can instead be preprogrammed with the required compensation information and algorithms to check that the time and date information in the multiplexed data stream is the same as or later than the time and date information from its own clock and calendar before adjusting any PID values.
  • the preprogramming takes place in conjunction with preplanning of how the false PID values are to be included in the multiplexed packet streams. This tie-in will not always be ideal, and if details thereof needed to be changed, then the microprocessor will need to be amended.
  • the required compensation information can be supplied after installation of microprocessors 224 and 211, and/or regularly updated, in various ways.
  • microprocessor 224 of controlled access module 204 has the relevant information input into it from a smart card.
  • a smart card could therefore be provided on a conventional commercial basis.
  • the smart card may also serve as a conventional smart card enabling descrambling on a commercial basis, or could be an additional smart card.
  • the correction instructions can themselves be supplied as part of the broadcasts received by host apparatus 202 and controlled access module 204. In this case microprocessor 224 would be preprogrammed to extract the relevant correction information from broadcasts. Such correction instructions could themselves be scrambled requiring descrambling by descrambler 218.
  • the present invention can also be embodied in other digital TV arrangements and systems, and also in any other suitable communications systems, including ones other than television, for example radio, telephony and so on.

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Databases & Information Systems (AREA)
  • Computer Security & Cryptography (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Two-Way Televisions, Distribution Of Moving Picture Or The Like (AREA)

Abstract

L'invention concerne un procédé et un système de génération de données de radiodiffusion numérique destinés à la transmission. Des paquets contenant des données provenant de trains de données élémentaires et des codes d'identification correspondant sont formés. Des paquets contenant des informations d'identification indiquant la correspondance entre les codes d'identification et les trains de données élémentaires sont également formés. Les paquets sont constitués en un train de données multiplexé. Une indication erronée de la correspondance d'au moins un code d'identification est utilisée. L'invention concerne également un procédé et un système qui traitent les données de radiodiffusion numérique comprenant lesdits codes d'identification erronés en corrigeant les codes erronés. On décrit un procédé interdisant la copie. Le procédé élimine également la nécessité d'un signal univoque entre le module de contrôle d'accès et un appareil hôte. Le procédé de l'invention s'applique à des systèmes de radiodiffusion conformes aux normes DVB et MPEG-2.
EP00962711A 1999-09-27 2000-09-22 Procede empechant la copie de donnees numeriques Withdrawn EP1287695A1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
GB9922862A GB2354677A (en) 1999-09-27 1999-09-27 Copy protection of digital video broadcast data
GB9922862 1999-09-27
PCT/GB2000/003653 WO2001024529A1 (fr) 1999-09-27 2000-09-22 Procede empechant la copie de donnees numeriques

Publications (1)

Publication Number Publication Date
EP1287695A1 true EP1287695A1 (fr) 2003-03-05

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Family Applications (1)

Application Number Title Priority Date Filing Date
EP00962711A Withdrawn EP1287695A1 (fr) 1999-09-27 2000-09-22 Procede empechant la copie de donnees numeriques

Country Status (4)

Country Link
EP (1) EP1287695A1 (fr)
AU (1) AU7435700A (fr)
GB (1) GB2354677A (fr)
WO (1) WO2001024529A1 (fr)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
PL367377A1 (en) * 2004-04-19 2005-10-31 Advanced Digital Broadcast Ltd. Method for transmission protection, method for transmission, method for reception, transmitter and receiver of radio or tv data
KR100810318B1 (ko) * 2006-02-08 2008-03-07 삼성전자주식회사 디지털 멀티미디어 방송 제한 서비스 시스템 및 그 방법
FR2970616B1 (fr) * 2011-01-17 2014-06-13 Sist Holding Procede d'acces a des programmes a partir de postes de television et systeme associe.

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB8310315D0 (en) * 1983-04-15 1983-05-18 British Broadcasting Corp Multiplexed digital data transmission
US5649029A (en) * 1991-03-15 1997-07-15 Galbi; David E. MPEG audio/video decoder
FI100684B (fi) * 1995-11-30 1998-01-30 Nokia Oy Ab Pakettivälitteisen tiedonsiirtomuodon pakettitunnisteiden käyttö vasta anottajien osoittamiseen
US5757922A (en) * 1995-12-08 1998-05-26 Nippon Telegraph & Telephone Corp. Method and system for packet scrambling communication with reduced processing overhead
US5844478A (en) * 1996-05-31 1998-12-01 Thomson Consumer Electronics, Inc. Program specific information formation for digital data processing
JP3216531B2 (ja) * 1996-07-24 2001-10-09 三菱電機株式会社 再多重化装置および再多重化方法
JPH1093914A (ja) * 1996-09-18 1998-04-10 Sony Corp データ伝送方法、データ送信装置、データ受信装置のパラメータ設定方法、データ受信装置、データ伝送システム、再生方法、及び再生装置
JP2000514271A (ja) * 1996-10-08 2000-10-24 ティアナン・コミュニケーションズ・インコーポレーテッド マルチサービストランスポートの多重化装置およびその方法
JP4018823B2 (ja) * 1997-10-24 2007-12-05 株式会社大宇エレクトロニクス Ｍｐｅｇ−２放送プログラムの貯蔵及び再生システム

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0124529A1 *

Also Published As

Publication number Publication date
GB9922862D0 (en) 1999-12-01
GB2354677A (en) 2001-03-28
WO2001024529A1 (fr) 2001-04-05
AU7435700A (en) 2001-04-30

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