Chunk Header Incorporating Binary Flags and Correlated Variable-Length Fields

• US 20090132721A1
• Filed: 11/17/2008
• Published: 05/21/2009
• Est. Priority Date: 11/16/2007
• Status: Active Grant

• Current Assignee: Sonic IP Incorporated (Endeavor Group Holdings Inc.)
• Original Assignee: DivX, LLC (f/k/a DivX CF Holdings LLC) (SoftBank Group Corp.)
• Inventors: Funnell, John, Vashisht-Rota, Jerome, Floyd, Michael, Frantz, William, Soroushian, Kourosh, Osborne, Roland, Priyadarshi, Shaiwal, Salmonsen, Dan, Braness, Jason
• Granted Patent: US 8,301,793 B2
• Time in Patent Office: Days
• US Class Current: 709/231
• CPC Class Codes: G06F 16/4393 Multimedia presentations, e.g. slide shows, multimedia albums
• CPC Class Codes: G11B 27/105 of operating discs
• CPC Class Codes: G11B 27/30 on the same track as the main recording
• CPC Class Codes: G11B 27/34 Indicating arrangements indicating means incorporated in magazine or cassette G11B23/046 and G11B23/0875; indicating measured values in general G01D
• CPC Class Codes: H04L 67/10 in which an application is distributed across nodes in the network software deployment G06F8/60; multiprogramming arrangements G06F9/46
• CPC Class Codes: H04N 9/79 Processing of colour television signals in connection with recording

Abstract

Playback and distribution systems and methods for multimedia files are provided. The multimedia files are encoded with flags associated with the content data of the multimedia files. Through the use of the flags, playback of the content is enhanced without significantly increasing the file size of the multimedia file.

Claims

1. A method of playing back content by a playback device stored in a media file supplied by a media server, comprising:

providing a media file having content data and header, the content data having a plurality of media frames and the header having a plurality of flags or elements;

decoding the content data by a playback device;

displaying content on a display screen from the decoded content data;

receiving a user request;

identifying a flag or element from the plurality of flags or elements based on the received user request; and

decoding one or more media frames from the subset of the plurality of media frames based on the identified flag or element.

2. The method of claim 1 wherein the header further comprises a plurality of data fields and wherein the plurality of flags and data fields of the header references portions of the content data.

3. The method of claim 1 wherein the plurality of flags are ordered from highest importance to lowest importance.

4. The method of claim 1 wherein the plurality of elements each contain a unique identification field, size and data fields.

5. The method of claim 4 wherein at least one unique identification field corresponds to a forward access identifier and at least one data field follows the forward access identifier and includes a forward offset data field having a offset value relative to a position of a frame being displayed or a start point of the media file.

6. The method of claim 4 wherein at least one unique identification field corresponds to a backward access identifier and at least one data field follows the backward access identifier and includes a backward offset data field.

7. The method of claim 6 wherein the backward offset data field has a pointer to a previous key-frame block.

8. The method of claim 6 wherein the backward offset data field has a value corresponding to a previous key-frame time code.

9. The method of claim 2 wherein the plurality of flags include a forward access flag and the plurality of data fields include a forward offset data field, the forward access flag referencing the forward offset data field.

10. The method of claim 2 wherein the plurality of flags include a backward access flag and the plurality of data fields include a backward offset data field, the backward access flag referencing the backward offset data filed.

11. The method of claim 9 wherein the forward offset data field has a pointer to a next key-frame chunk, the next key-frame chunk arranged to be decoded independently of any other chunks and providing an access point during trick-play operations.

12. The method of claim 11 wherein the pointer is an offset value calculated from a position of a frame being displayed.

13. The method of claim 9 wherein the forward offset data field defines a bit-field representation relative to a start point in the media file.

14. The method of claim 2 wherein each flag of the plurality of flags has a one to one corresponding reference to each data field of the plurality of data fields.

15. The method of claim 2 wherein the plurality of flags and the plurality of data fields include information located within a chunk in the content data.

16. The method of claim 14 further comprising decoding the chunk in which at least one flag of the plurality of flags is decoded.

17. The method of claim 16 further comprising bypassing decoding of a remainder of the chunk based on the decoded flag.

18. The method of claim 17 further comprising bypassing decoding of a portion of the chunk based on the decoded flag.

19. The method of claim 16 further comprising decoding only a portion of the chunk based on the decoded flag.

20. The method of claim 16 further comprising decoding another chunk within the media file based on the decoded flag.

21. The method of claim 19 wherein the decoded flag references a data field of the plurality of data fields that points directly to a particular media frame of the content data.

22. The method of claim 4 further comprising decoding the chunk in which at least one element of the plurality of elements is decoded.

23. The method of claim 22 further comprising bypassing decoding of a remainder of the chunk based on the decoded element.

24. The method of claim 22 further comprising bypassing decoding of a portion of the chunk based on the decoded element.

25. The method of claim 22 further comprising decoding only a portion of the chunk based on the decoded element.

26. The method of claim 22 further comprising decoding another chunk within the media file based on the decoded element.

27. The method of claim 22 wherein the decoded element references a data field of the plurality of data fields that points directly to a particular media frame of the content data.

28. A playback device for decoding a media file, the device comprising:

a de-multiplexer arranged to receive and decipher a media file having content data and a header having a plurality of flags or uniquely defined elements;

a video decoder coupled to the de-multiplexer and arranged to receive video portions of the deciphered media file;

an audio decoder coupled to the de-multiplexer and arranged to receive audio portions of the deciphered media file;

wherein the de-multiplexer selects the video portions and the audio portions to be transmitted to the respective video and audio decoder based on the plurality of flags or uniquely defined elements from the deciphered media file.

29. The device of claim 28 further comprising:

a storage media storing the media file; and

a controller coupled to the storage media and arranged to retrieve the media file from the storage media based on a user request and transmit to the media file to the de-multiplexer.

30. The device of claim 29 further comprising a synchronization circuitry coupled to the video and audio decoders, the video and audio decoders decoding respective video and audio chunk data and supplying the decoded video and chunk data to the synchronization circuitry.

31. The device of claim 30 wherein the de-multiplexer extracts timing information from the plurality of flags or uniquely defined elements from the deciphered media file and supplies the timing information to the synchronization circuitry, the synchronization circuitry synchronizing playback of the decoded video and chunk data from the video and audio decoders based on the supplied timing information.

32. The device of claim 31 wherein the plurality of flags or uniquely defined elements include a forward access flag or unique element and the media file includes a plurality of data fields having a forward offset data field, the forward access flag or unique element referencing the forward offset data field, the forward offset data field having a pointer to a key-frame chunk and accessible by the de-multiplexer.

33. The device of claim 32 wherein the de-multiplexer supplies the key-frame chunk to the video and audio decoders to be decoded independently of any other chunks based on the pointer from the forward offset data field.

34. The device of claim 31 wherein the plurality of flags or unique elements include a backward access flag and the media file includes a plurality of data fields having a backward offset data field, the backward access flag referencing the backward offset data field, the backward offset data field having a pointer to a key-frame chunk and accessible by the de-multiplexer.

35. The device of claim 34 wherein the de-multiplexer supplies the previous and next key-frame chunk to the video and audio decoders to be decoded independently of any other chunks based on the pointer from the backward offset data field.