System for preventing playback of unauthorized digital video recordings

• US 6,466,670 B1
• Filed: 01/11/2000
• Issued: 10/15/2002
• Est. Priority Date: 05/21/1998
• Status: Expired due to Term

• Current Assignee: Synamedia Limited
• Original Assignee: NDS Limited (Cisco Systems, Inc.)
• Inventors: Sered, Yishai, Tsuria, Yossef
• Primary Examiner(s): Smithers, Matthew
• Application Number:
  US09/481,739
• Time in Patent Office: 1,008 Days
• Field of Search: 380/202, 380/201, 380/210, 380/214, 380/215, 380/217, 380/241, 380/242, 173/176, 173/168, 705/51, 705/57, 705/58
• US Class Current: 380/202
• CPC Class Codes: G06F 16/785 using colour or luminescence
• CPC Class Codes: G06V 20/40 in video content extracting overlay text G06V20/62; video retrieval G06F16/70; processing of video elementary streams in video servers H04N21/234; processing of video elementary streams in video clients H04N21/44
• CPC Class Codes: H04N 19/467 characterised by the embedded information being invisible, e.g. watermarking
• CPC Class Codes: H04N 2005/91335 the copy protection signal being a watermark
• CPC Class Codes: H04N 2005/91342 the copy protection signal being an authentication signal
• CPC Class Codes: H04N 21/4627 Rights management associated to the content security in data switching network management H04L41/28; security management or policies for network security H04L63/20; access security in wireless networks H04W12/08
• CPC Class Codes: H04N 21/8352 involving content or source identification data, e.g. Unique Material Identifier [UMID]
• CPC Class Codes: H04N 5/913 for scrambling ; for copy protection
• CPC Class Codes: H04N 7/162 Authorising the user terminal, e.g. by paying; Registering the use of a subscription channel, e.g. billing

Abstract

This invention discloses an anti-piracy system including video representation signature apparatus for computing a forbidden signature of a forbidden video representation, communication apparatus for communicating the forbidden signature to a playing device, and a playing device adapted to receive and play back a recorded video representation, the playing device including reception apparatus for receiving the forbidden signature communicated by the communication apparatus, recorded video representation signature apparatus for computing a signature of the recorded video representation, and playback control apparatus operative to prevent playback of the recorded video representation if the computed signature of the recorded video representation matches the forbidden signature communicated to the playing device

Claims

1. A method for assigning a signature to a video representation, the video representation comprising a plurality of frames, the method comprising:

choosing a chosen plurality of frames from among the plurality of frames comprised in the video representation;

for each of the chosen plurality of frames, computing a frame characteristic value, thus producing a plurality of frame characteristic values;

computing a function of the plurality of frame characteristic values and assigning a result of the function as the signature;

communicating the signature to a playing device;

providing a recorded video representation to the playing device;

computing a signature of the recorded video representation; and

preventing playback of the video representation in the playing device if the computed signature of the recorded video representation matches the signature communicated to the playing device.

2. A method according to claim 1 and wherein the function comprises concatenation of the plurality of frame characteristic values.

3. A method according to claim 1 and wherein the video representation comprises an MPEG representation, and

each of the chosen plurality of frames comprises an I-frame.

4. A method according to claim 1 and wherein the step of preventing playback comprises:

preventing playback of the video representation in the playing device if the computed signature of the recorded video representation is identical to the signature communicated to the playing device.

5. A method according to claim 1 and wherein the step of preventing playback comprises:

employing a signature comparison method to determine whether the computed signature of the recorded video representation matches the signature communicated to the playing device, and

the signature comparison method includes determining that a first signature and a second signature match even if the first signature is not identical to the second signature.

6. A method according to claim 1 and wherein the step of computing a frame characteristic value comprises:

dividing the frame into a plurality of regions;

choosing one of the plurality of regions; and

computing a region characteristic value of the chosen region and assigning the region characteristic value as the frame characteristic value.

7. A method according to claim 6 and wherein the region characteristic value comprises a function of average pixel value for the region.

8. A method according to claim 7 and wherein the function of average pixel value produces a 1-bit value.

9. A method according to claim 8 and wherein the function of average pixel value produces a 1-bit value of “

1”

for a first one of the chosen plurality of frames.

10. A method according to claim 6 and wherein the step of dividing the frame into a plurality of regions comprises, for each frame in the chosen plurality of frames, dividing the frame into a plurality of regions each corresponding to one of the plurality of regions into which every other frame of the chosen plurality of frames is divided.

11. A method according to claim 10 and wherein the step of choosing one of the plurality of regions comprises choosing, for each frame in the chosen plurality of frames, a region corresponding to the region chosen in every other frame of the chosen plurality of frames.

12. A method according to claim 10 and wherein the step of choosing one of the plurality of regions comprises choosing, for at least one frame in the chosen plurality of frames, a region not corresponding to a region chosen in at least one other frame of the chosen plurality of frames.

13. A system for assigning a signature to a video representation, the video representation comprising a plurality of frames, the system comprising:

frame selection apparatus for choosing a chosen plurality of frames from among the plurality of frames comprised in the video representation;

a frame characteristic determination unit operative, for each of the chosen plurality of frames, to compute a frame characteristic value, thus producing a plurality of frame characteristic values;

signature apparatus for computing a function of the plurality of frame characteristic values and assigning a result of the function as the signature; and

communication apparatus for communicating the signature to a playing device,

wherein the playing device comprises;

a receiving unit for receiving a recorded video representation;

signature apparatus for computing a signature of the recorded video representation; and

playback control apparatus for preventing playback of the video representation in the playing device if the computed signature of the recorded video representation matches the signature communicated to the playing device.

14. A method for assigning a signature to a video representation, the video representation comprising a plurality of frames, the method comprising:

choosing a chosen plurality of frames from among the plurality of frames comprised in the video representation;

for each of the chosen plurality of frames, computing a frame characteristic value, thus producing a plurality of frame characteristic values;

computing a function of the plurality of frame characteristic values and assigning a result of the function as the signature; and

communicating the signature to a playing device,

wherein the step of computing a frame characteristic value comprises;

dividing the frame into a plurality of regions;

choosing one of the plurality of regions; and

computing a region characteristic value of the chosen region and assigning the region characteristic value as the frame characteristic value, and

the region characteristic value comprises a function of average pixel value for the region, and

the function of average pixel value produces a 1-bit value.

15. A method according to claim 14 and wherein the function comprises concatenation of the plurality of frame characteristic values.

16. A method according to claim 14 and wherein the video representation comprises an MPEG representation, and

each of the chosen plurality of frames comprises an I-frame.

17. A method according to claim 14 and also comprising:

providing a recorded video representation to the playing device;

computing a signature of the recorded video representation; and

preventing playback of the video representation in the playing device if the computed signature of the recorded video representation matches the signature communicated to the playing device,

wherein the step of preventing playback comprises;

preventing playback of the video representation in the playing device if the computed signature of the recorded video representation is identical to the signature communicated to the playing device.

18. A method according to claim 14 and also comprising:

providing a recorded video representation to the playing device;

computing a signature of the recorded video representation; and

preventing playback of the video representation in the playing device if the computed signature of the recorded video representation matches the signature communicated to the playing device,

wherein the step of preventing playback comprises;

employing a signature comparison method to determine whether the computed signature of the recorded video representation matches the signature communicated to the playing device, and

the signature comparison method includes determining that a first signature and a second signature match even if the first signature is not identical to the second signature.

19. A method according to claim 14 and wherein the function of average pixel value produces a 1-bit value of “

1”

for a first one of the chosen plurality of frames.

20. A method according to claim 14 and wherein the step of dividing the frame into a plurality of regions comprises, for each frame in the chosen plurality of frames, dividing the frame into a plurality of regions each corresponding to one of the plurality of regions into which every other frame of the chosen plurality of frames is divided.

21. A method according to claim 20 and wherein the step of choosing one of the plurality of regions comprises choosing, for each frame in the chosen plurality of frames, a region corresponding to the region chosen in every other frame of the chosen plurality of frames.

22. A method according to claim 20 and wherein the step of choosing one of the plurality of regions comprises choosing, for at least one frame in the chosen plurality of frames, a region not corresponding to a region chosen in at least one other frame of the chosen plurality of frames.

23. A system for assigning a signature to a video representation, the video representation comprising a plurality of frames, the system comprising:

frame selection apparatus for choosing a chosen plurality of frames from among the plurality of frames comprised in the video representation;

a frame characteristic determination unit operative, for each of the chosen plurality of frames, to compute a frame characteristic value, thus producing a plurality of frame characteristic values;

signature apparatus for computing a function of the plurality of frame characteristic values and assigning a result of the function as the signature; and

communication apparatus for communicating the signature to a playing device,

wherein the frame characteristic determination unit is operative to compute the frame characteristic value by;

dividing the frame into a plurality of regions;

choosing one of the plurality of regions; and

computing a region characteristic value of the chosen region and assigning the region characteristic value as the frame characteristic value, and

the region characteristic value comprises a function of average pixel value for the region, and

the function of average pixel value produces a 1-bit value.

24. An anti-piracy method comprising:

computing a forbidden signature of a forbidden video representation;

communicating the forbidden signature to a playing device;

providing a recorded video representation to the playing device;

computing a signature of the recorded video representation; and

preventing playback of the recorded video representation in the playing device if the computed signature of the recorded video representation matches the forbidden signature communicated to the playing device.

25. A method according to claim 24 and also comprising:

storing the forbidden signature at the playing device; and

retrieving the forbidden signature before performing the preventing playback step.

26. An anti-piracy system comprising:

video representation signature apparatus for computing a forbidden signature of a forbidden video representation;

communication apparatus for communicating the forbidden signature to a playing device; and

a playing device adapted to receive and play back a recorded video representation, the playing device comprising;

reception apparatus for receiving the forbidden signature communicated by the communication apparatus;

recorded video representation signature apparatus for computing a signature of the recorded video representation; and

playback control apparatus operative to prevent playback of the recorded video representation if the computed signature of the recorded video representation matches the forbidden signature communicated to the playing device.

27. A system according to claim 26 and wherein the reception apparatus is operative to receive the forbidden signature during playback of a non-forbidden recorded video representation.

28. A system according to claim 27 and wherein the reception apparatus is also operative to receive an authorization message authorizing playback of the non-forbidden recorded video representation, and

the authorization message comprises the forbidden signature.

29. A playing device adapted to receive and play back a recorded video representation the playing device comprising:

reception apparatus for receiving a forbidden signature of a forbidden video representation;

recorded video representation signature apparatus for computing a signature of the recorded video representation; and

playback control apparatus operative to prevent playback of the recorded video representation if the computed signature of the recorded video representation matches the forbidden signature received by the playing device.

30. Apparatus according to claim 29 and also comprising:

forbidden signature storage apparatus operative to store the forbidden signature, and wherein

the playback control apparatus receives the forbidden signature from the forbidden signature storage apparatus.