Digital media universal elementary stream

• US 20050234731A1
• Filed: 10/14/2004
• Published: 10/20/2005
• Est. Priority Date: 04/14/2004
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Thumpudi, Naveen, Johnston, James D., Sirivara, Sudheer, Chen, Wei-ge, Smirnov, Sergey, Messer, Chris
• Granted Patent: US 8,131,134 B2
• Time in Patent Office: Days
• US Class Current: 704/500
• CPC Class Codes: G10L 19/167 Audio streaming, i.e. formatting and decoding of an encoded audio signal representation into a data stream for transmission or storage purposes

Abstract

Described techniques and tools include techniques and tools for mapping digital media data (e.g., audio, video, still images, and/or text, among others) in a given format to a transport or file container format useful for encoding the data on optical disks such as digital video disks (DVDs). A digital media universal elementary stream can be used to map digital media streams (e.g., an audio stream, video stream or an image) into any arbitrary transport or file container, including optical disk formats, and other transports, such as broadcast streams, wireless transmissions, etc. The information to decode any given frame of the digital media in the stream can be carried in each coded frame. A digital media universal elementary stream includes stream components called chunks. An implementation of a digital media universal elementary stream arranges data for a media stream in frames, the frames having one or more chunks.

Claims

1. In a digital media system, a method of mapping digital media data in a first format onto a transport format, the method comprising:

obtaining digital media data encoded in the first format;

arranging the obtained digital media data in a frame arrangement, the frame arrangement of digital media data having a size and comprising a digital media data chunk and a metadata chunk, the frame arrangement operable to allow a digital video disk decoder to access and decode the digital media data chunk; and

inserting the frame arrangement of digital media data in a digital media data stream in the transport format.

2. The method of claim 1, wherein the digital media data is audio, and the transport format is for storing audio data on a computer-readable optical data storage disk.

3. The method of claim 1 wherein the first format is a Windows Media Audio format and the second format is a DVD-A compressed audio format.

4. The method of claim 1 wherein the first format is a Windows Media Audio format and the second format is a DVD audio recording format.

5. The method of claim 1 wherein the metadata chunk comprises information indicating metadata size.

6. The method of claim 5 wherein the metadata chunk comprises information indicating metadata type.

7. The method of claim 1 wherein the frame arrangement further comprises a cyclic redundancy check chunk.

8. The method of claim 1 wherein the frame arrangement further comprises a synchronization chunk, the synchronization chunk comprising a length field for verifying a valid synchronization pattern.

9. The method of claim 1 wherein the frame arrangement further comprises a format header chunk, the format header chunk including stream properties.

10. The method of claim 1 wherein the frame arrangement further comprises content descriptor metadata.

11. The method of claim 1 wherein the size is a fixed size.

12. The method of claim 1 wherein the size is a variable size.

13. The method of claim 1 wherein the first format is a Windows Media Audio format and the second format is an MPEG-2 Program Stream format.

14. A computer-readable medium having stored thereon computer-readable instructions for causing a digital media processor to perform the method of claim 1.

15. In a digital signal processor, a method of mapping audio data to a format for storing audio data on a computer-readable optical data storage disk, the method comprising:

obtaining audio data;

converting the obtained audio data to an audio data access unit having a fixed size, the audio data access unit comprising an audio data chunk, a synchronization chunk, a metadata chunk, and a cyclic redundancy check chunk; and

inserting the audio data access unit in an audio data stream in the format for storing audio data on a computer-readable optical data storage disk.

16. In a digital media system, a method of decoding audio data in a format for storing audio data on a computer-readable optical data storage disk, the method comprising:

obtaining audio data encoded in the format for storing audio data on a computer-readable optical data storage disk, the obtained audio data in a frame arrangement having a fixed size and comprising an audio data chunk and a metadata chunk, the frame arrangement comprising audio data transcoded from an intermediate format; and

decoding the obtained audio data.

17. The method of claim 16 wherein the intermediate format is a Windows Media Audio format, and wherein the format for storing audio data on a computer-readable optical data storage disk is a DVD format.

18. In a digital media system, a method of encoding digital media data as a universal elementary stream for mapping into a transport container, the method comprising:

obtaining a digital media stream encoded according to a selected digital media codec;

arranging the obtained digital media stream in an elementary stream having a frame arrangement, wherein a frame comprises a plurality of syntax elements, including at least a metadata element, a synchronization pattern element and a length element denoting a distance from a synchronization pattern of a next proximate frame; and

inserting the elementary stream in the transport container.

19. A method of decoding digital media data encoded according to the method of claim 18, the method comprising:

separating the elementary stream from the transport container;

parsing the elementary stream to identify a first occurrence of the synchronization pattern and length;

parsing the elementary stream to identify a second occurrence of the synchronization pattern at a distance denoted by the length; and

identifying a frame of the elementary stream from the identified occurrences of the synchronization pattern.

20. The method of claim 18, wherein the syntax elements further include a plurality of optional chunk components, each chunk component having a syntax element denoting a type of the chunk component, the synchronization pattern and length syntax elements defining an extent of the frame irrespective of the inclusion in or omission from the frame of any particular types of chunk components.

21. The method of claim 20, wherein an encoding scheme of the type of chunk component syntax element includes an escape code for later extensions to the elementary stream definition.

22. The method of claim 18, wherein the syntax elements of another frame in the frame arrangement includes an end of block chunk component in lieu of the synchronization block to denote an end of such other frame.

23. In a digital media system, a method of encoding digital media data as a universal elementary stream for mapping into a transport container, the method comprising:

obtaining a digital media stream encoded according to a selected digital media codec;

arranging the obtained digital media stream in an elementary stream having a frame arrangement, wherein a frame comprises a plurality of syntax elements, including at least a codec properties chunk element denoting the selected digital media codec; and

inserting the elementary stream in the transport container.

24. The method of claim 23 wherein the codec properties chunk element denoting the selected digital media codec includes version information for the selected digital media codec.

25. A method of mapping digital media data in at least one raw format into a storage, transmission or delivery transport container format, the method comprising:

obtaining data of the at least one raw format, and any side, metadata, or ancillary information required to scan, parse, transmit, decode or present the at least one raw format;

arranging the data as a sequence of chunk components into an elementary stream, the chunk components being from a group of optionally inclusive chunk types encoded in a predefined chunk type header of the chunk components, wherein the arranging includes or omits chunk components of the optionally inclusive chunk types from coding into the bitstream as desired or required for the format, storage, transmission, delivery, or rendering of the digital media, said sequence of chunks consisting of at least one chunk component containing raw media data, and at least one chunk component containing said side, metadata or ancillary information;

combining the chunks of the elementary stream into a sequential set of packets or a serial stream of a transport container format for self-contained storage, transmission, delivery or rendering of the digital media.