Dynamic composition of pre-encrypted video on demand content

• US 20050094808A1
• Filed: 03/16/2004
• Published: 05/05/2005
• Est. Priority Date: 10/31/2003
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.), Sony Electronics Inc. (Sony Group Corp.)
• Inventors: Pedlow, Leo M. Jr., Agnihotri, Davender
• Granted Patent: US 7,346,163 B2
• Time in Patent Office: Days
• US Class Current: 380/200
• CPC Class Codes: G11B 27/005 Reproducing at a different information rate from the information rate of recording for television signals H04N5/783
• CPC Class Codes: G11B 27/322 used signal is digitally coded
• CPC Class Codes: H04N 21/23439 for generating different versions
• CPC Class Codes: H04N 21/23473 by pre-encrypting
• CPC Class Codes: H04N 21/23476 by partially encrypting, e.g. encrypting the ending portion of a movie
• CPC Class Codes: H04N 21/2362 Generation or processing of Service Information [SI]
• CPC Class Codes: H04N 21/2387 Stream processing in response to a playback request from an end-user, e.g. for trick-play
• CPC Class Codes: H04N 21/47202 for requesting content on demand, e.g. video on demand
• CPC Class Codes: H04N 21/8453 by locking or enabling a set of features, e.g. optional functionalities in an executable program
• CPC Class Codes: H04N 7/1675 Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58
• CPC Class Codes: H04N 7/17336 Handling of requests in head-ends

Abstract

According to certain embodiments consistent with the present invention, a method of processing digital video content, wherein the digital video content comprises intra-coded frames and inter-coded frames, involves selecting a plurality of the intra-coded frames for encryption to produce selected frames; encrypting the selected frames under a first encryption algorithm to produce first encrypted frames; storing the inter-coded frames in a first file; and storing the intra-coded frames, whether encrypted under the first encryption algorithm or unencrypted, in a second file. For a multiple encryption embodiment consistent with the present invention, the method further involves duplicating the intra-coded frames; encrypting duplicates of the selected frames under a second encryption algorithm to produce second encrypted frames; storing the intra-coded frames, whether encrypted under the second encryption algorithm or unencrypted, in a third file. This abstract is not to be considered limiting, since other embodiments may deviate from the features described in this abstract.

Claims

1. A method of processing digital video content, wherein the digital video content comprises intra-coded frames and inter-coded frames, the method comprising:

selecting a plurality of the intra-coded frames for encryption to produce selected frames;

encrypting the selected frames under a first encryption algorithm to produce first encrypted frames;

storing the inter-coded frames in a first file; and

storing the intra-coded frames, whether encrypted under the first encryption algorithm or unencrypted, in a second file.

2. The method according to claim 1, further comprising:

duplicating the intra-coded frames;

encrypting duplicates of the selected frames under a second encryption algorithm to produce second encrypted frames;

storing the intra-coded frames, whether encrypted under the second encryption algorithm or unencrypted, in a third file.

3. The method according to claim 2, further comprising:

receiving a request from a subscriber terminal for the digital content;

determining that the subscriber is enabled for decryption of content under the second encryption algorithm;

retrieving the content from the first file and the third file; and

sending the content to the subscriber terminal.

4. The method according to claim 3, wherein the content is retrieved from the first and third files in an order of sequential frames in the content.

5. The method according to claim 2, further comprising:

receiving a request from a subscriber terminal for the digital content;

determining that the subscriber is enabled for decryption of content under the first encryption algorithm;

retrieving the content from the first file and the second file; and

sending the content to the subscriber terminal.

6. The method according to claim 5, wherein the content is retrieved from the first and second files in an order of sequential frames in the content.

7. The method according to claim 1, further comprising:

receiving a request from a subscriber terminal for the digital content;

determining that the subscriber is enabled for decryption of content under the first encryption algorithm;

retrieving the content from the first file and the second file; and

sending the content to the subscriber terminal.

8. The method according to claim 7, wherein the content is retrieved from the first and second files in an order of sequential frames in the content.

9. The method according to claim 2, further comprising:

receiving a request from a subscriber terminal for the digital content in a trick play mode;

determining that the subscriber is enabled for decryption of content under the second encryption algorithm;

retrieving the intra-coded frames from the third file; and

sending the inter-coded frames to the subscriber terminal.

10. The method according to claim 1, further comprising:

receiving a request from a subscriber terminal for the digital content in a trick play mode;

determining that the subscriber is enabled for decryption of content under the first encryption algorithm;

retrieving the intra-coded frames from the second file; and

sending the inter-coded frames to the subscriber terminal.

11. The method according to claim 1, wherein the digital content comprises MPEG encoded digital content, and wherein the intra-coded frames comprise I-frames, and wherein the inter-coded frames comprise B-frames and P-frames.

12. A method of processing digital video content, wherein the digital video content comprises intra-coded frames and inter-coded frames, the method comprising:

duplicating the intra-coded frames;

selecting a plurality of the intra-coded frames for encryption to produce selected frames;

encrypting the selected frames under a first encryption algorithm to produce first encrypted frames;

encrypting the duplicates of the selected frames under a second encryption algorithm to produce second encrypted frames;

storing the inter-coded frames in a first file;

storing the intra-coded frames, whether encrypted under the first encryption algorithm or unencrypted, in a second file; and

storing the intra-coded frames, whether encrypted under the second encryption algorithm or unencrypted, in a third file.

13. The method according to claim 12, further comprising:

receiving a request from a subscriber terminal for the digital content;

determining that the subscriber is enabled for decryption of content under the second encryption algorithm;

retrieving the content from the first file and the third file; and

sending the content to the subscriber terminal.

14. The method according to claim 13, wherein the content is retrieved from the first and third files in an order of sequential frames in the content.

15. The method according to claim 12, further comprising:

receiving a request from a subscriber terminal for the digital content;

determining that the subscriber is enabled for decryption of content under the first encryption algorithm;

retrieving the content from the first file and the second file; and

sending the content to the subscriber terminal.

16. The method according to claim 15, wherein the content is retrieved from the first and second files in an order of sequential frames in the content.

17. The method according to claim 12, further comprising:

receiving a request from a subscriber terminal for the digital content in a trick play mode;

determining that the subscriber is enabled for decryption of content under the second encryption algorithm;

retrieving the intra-coded frames from the third file; and

sending the inter-coded frames to the subscriber terminal.

18. The method according to claim 12, further comprising:

receiving a request from a subscriber terminal for the digital content in a trick play mode;

determining that the subscriber is enabled for decryption of content under the first encryption algorithm;

retrieving the intra-coded frames from the second file; and

sending the inter-coded frames to the subscriber terminal.

19. A method of processing digital video content, wherein the digital video content comprises intra-coded frames and inter-coded frames, the method comprising:

selecting a plurality of the intra-coded frames for encryption to produce selected frames;

encrypting the selected frames under a first encryption algorithm to produce first encrypted frames;

storing the inter-coded frames in a first file;

storing the intra-coded frames, whether encrypted under the first encryption algorithm or unencrypted, in a second file;

duplicating the intra-coded frames;

encrypting duplicates of the selected frames under a second encryption algorithm to produce second encrypted frames;

storing the intra-coded frames, whether encrypted under the second encryption algorithm or unencrypted, in a third file;

receiving a request from a subscriber terminal for the digital content;

determining that the subscriber is enabled for decryption of content under the second encryption algorithm;

retrieving the content from the first file and the third file; and

sending the content to the subscriber terminal.

20. The method according to claim 19, wherein the content is retrieved from the first and third files in an order of sequential frames in the content.

21. A computer readable storage device for storing digital video content, comprising:

at least one computer readable storage medium;

a first file stored on the storage medium containing un-encrypted inter-coded frames of the digital video content;

a second file stored on the storage medium containing intra-coded frames of the digital video content encrypted under a first encryption algorithm;

a third file stored on the storage medium containing intra-coded frames of the digital video content encrypted under a second encryption algorithm;

a first reference table that relates frames in the first file to frames in the second file; and

a second reference table that relates frames in the first file to frames in the third file.

22. The storage device according to claim 21, wherein the digital content comprises MPEG encoded digital content, and wherein the intra-coded frames comprise I-frames, and wherein the inter-coded frames comprise B-frames and P-frames.