METHODS AND SYSTEMS FOR SCALABLE VIDEO CHUNKING

• US 20110082945A1
• Filed: 07/23/2010
• Published: 04/07/2011
• Est. Priority Date: 08/10/2009
• Status: Active Grant

• Current Assignee: Bison Patent Licensing, LLC
• Original Assignee: SeaWell Networks, Inc. (CommScope Holding Company, Inc.)
• Inventors: Aitchison, Scott Ernest, Myers, Robert Linwood, Murray, Gregory Scott
• Granted Patent: US 8,566,393 B2
• Time in Patent Office: Days
• US Class Current: 709/231
• CPC Class Codes: H04L 65/60 Network streaming of media packets
• CPC Class Codes: H04N 21/234327 by decomposing into layers, e.g. base layer and one or more enhancement layers
• CPC Class Codes: H04N 21/2389 Multiplex stream processing, e.g. multiplex stream encrypting
• CPC Class Codes: H04N 21/4385 Multiplex stream processing, e.g. multiplex stream decrypting
• CPC Class Codes: H04N 21/4621 Controlling the complexity of the content stream or additional data, e.g. lowering the resolution or bit-rate of the video stream for a mobile client with a small screen arrangements for using the results of monitoring on user's side in broadcast systems H04H60/65; flow control in packet networks H04L47/10

Abstract

Methods and systems for creating and retrieving scalable media files using a chunking model. A plurality of network abstraction layer (NAL) units representing a scalable media presentation are grouped into a plurality of video chunks wherein each chunk represents only the NAL units of one layer and a specific time period. The plurality of video chunks are then stored in one or more scalable media files along with indexing information which provides information for retrieving the NAL units from each video chunk. In this manner, a client can request only the video chunks (and thus NAL units) that it needs or wants to achieve a specific bandwidth.

Claims

1. A method for generating a scalable media file, the method comprising:

(a) providing a plurality of network abstraction layer (NAL) units representing a scalable media presentation, each NAL unit being associated with one layer of a plurality of layers;

(b) grouping the plurality of NAL units into a plurality of video chunks, each video chunk comprising the NAL units associated with only one layer for a specific time period of the scalable media presentation;

(c) generating indexing information for each video chunk, the indexing information providing information for extracting the plurality of NAL units from the video chunk; and

(d) storing the plurality of video chunks and the associated indexing information in at least one scalable media file.

2. The method of claim 1, further comprising:

(e) generating retrieval information for the at least one scalable media file, the retrieval information providing information for retrieving the video chunks from the at least one scalable media file; and

(f) storing the retrieval information in the at least one scalable media file.

3. The method of claim 2, wherein the at least one scalable media file is comprised of a plurality of bytes and the retrieval information links each video chunk to a byte range of the at least one scalable media file.

4. The method of claim 3, wherein:

(A) the retrieval information comprises a byte range index and a plurality of byte range boxes;

(B) each byte range box specifies a plurality of byte ranges associated with a specific time period, each byte range corresponding to one video chunk of the plurality of video chunks; and

(C) the byte range index links each byte range with one layer of the plurality of layers.

5. The method of claim 1, further comprising:

(e) generating retrieval information for the at least one scalable media file, the retrieval information providing information for retrieving the video chunks from the at least one scalable media file; and

(f) storing the retrieval information in a separate scalable media file from the plurality of video chunks.

6. The method of claim 1, further comprising:

(e) providing a first plurality of audio samples associated with the plurality of NAL units, the first plurality of audio samples being associated with a first audio quality;

(f) grouping the first plurality of audio samples into a plurality of audio chunks, each audio chunk representing the first audio samples over a specific time period of the scalable media presentation; and

(g) storing the audio chunks in the at least one scalable media file.

7. The method of claim 6, further comprising:

(g) providing a second plurality of audio samples associated with the plurality of NAL units, the second plurality of audio samples being associated with a second audio quality;

(h) grouping the second plurality of audio samples into a plurality of audio chunks, each audio chunk comprising the second audio samples for a specific time period of the scalable media presentation; and

(i) storing the audio chunks in the at least one scalable media file.

8. The method of claim 1, wherein the indexing information comprises a decoding order number for each NAL unit of the associated video chunk.

9. The method of claim 1, wherein the indexing information comprises an offset and a length for each NAL unit of the associated video chunk.

10. The method of claim 1, further comprising:

(e) generating mapping information for each time period of the scalable media presentation, each mapping information providing information for retrieving the video chunks for the time period; and

(f) linking each mapping information with at least one video chunk of a preceding time period; and

(g) storing the mapping information in the at least one scalable media file.

11. The method of claim 10, wherein each mapping information is stored in the at least one scalable media file as part of the at least one video chunk of the preceding time period.

12. The method of claim 1, further comprising updating the at least one scalable media file with additional video chucks as additional NAL units are provided.

13. The method of claim 1, wherein the plurality of video chunks are stored in a single scalable media file.

14. The method of claim 13, wherein the plurality of video chunks are stored in the scalable media file in a contiguous manner, the order of the video chunks being based on inter-dependencies between the layers.

15. The method of claim 1, wherein the first NAL unit of each video chunk is an I-frame.

16. A method for receiving a scalable media presentation over a communications network, the method comprising:

(a) transmitting a request from a client device to a server for a scalable media presentation;

(b) receiving retrieval information from the server in response to the request for the scalable media presentation, the retrieval information providing information for retrieving a plurality of video chunks associated with the scalable media presentation, each video chunk comprising network abstraction layer (NAL) units associated with only one layer of a plurality of layers for a specific time period of the scalable media presentation;

(c) selecting a time period of the scalable media presentation to retrieve;

(d) selecting at least one video chunk associated with the selected time period based on the retrieval information;

(e) transmitting a request to the server for the at least one video chunk; and

(f) receiving the at least one video chunk and indexing information associated with the at least one video chunk from the server, the indexing information providing information for extracting the plurality of NAL units from the at least one video chunk; and

(g) extracting the NAL units from the at least one video chunk based on the indexing information associated with the at least one video chunk.

17. The method of claim 16, further comprising:

(h) selecting a subsequent time period of the scalable media presentation to retrieve; and

(i) repeating steps (d) to (h) until there are no more time periods of the scalable media presentation to retrieve.

18. The method of claim 16, wherein the indexing information comprises an offset and a length for each NAL unit in the associated video chunk, and step (g) comprises extracting each NAL unit from the at least one video chunk using the offset and length.

19. The method of claim 16, wherein the indexing information comprises a decoding order number for each NAL unit in the associated video chunk;

and the method further comprises ordering the extracted NAL units based on the decoding order numbers.

20. The method of claim 16, wherein the retrieval information links each video chunk to a specific byte range of an associated scalable media file;

and the request for the at least one video chunk is a byte range request based on the retrieval information.

21. The method of claim 20, wherein:

(A) the retrieval information comprises a byte range index and at least one byte range box;

(B) the at least one byte range box specifies a plurality of byte ranges associated with a specific time period, each byte range being associated with one video chunk; and

(C) the byte range index links each of the plurality of byte ranges with one layer of the plurality of layers.

22. The method of claim 16, wherein:

(A) the at least one video chunk comprises mapping information for retrieving the video chunks of a subsequent time period; and

(B) the method further comprises selecting at least one second video chunk to retrieve based on the mapping information of the at least one video chunk received.

23. The method of claim 16, wherein the retrieval information further provides information for retrieving a plurality of audio chunks, each audio chunk comprising audio samples for a specific time period of the scalable media presentation;

and the method further comprises;

(h) selecting at least one audio chunk associated with the selected time period based on the retrieval information;

(i) transmitting a request to the server for the selected at least one audio chunk;

(j) receiving the at least one audio chunk and indexing information associated with the at least one audio chunk; and

(k) extracting the audio samples from the at least one audio chunk based on the indexing information associated with the at least one audio chunk.

24. The method of claim 16, wherein the server is a web server and the request for the at least one video chunk is a HTTP byte range request.