UNIVERSAL CONTAINER FOR AUDIO DATA

• US 20080208601A1
• Filed: 04/25/2008
• Published: 08/28/2008
• Est. Priority Date: 07/02/2004
• Status: Active Grant

• Current Assignee: Douglas S. Wyatt, James E. Mccartney, William Stewart
• Original Assignee: Douglas S. Wyatt, James E. Mccartney, William Stewart
• Inventors: Stewart, William G., McCartney, James E., Wyatt, Douglas S.
• Granted Patent: US 8,095,375 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
• CPC Class Codes: G11B 27/105 of operating discs
• CPC Class Codes: G11B 27/3027 used signal is digitally coded
• CPC Class Codes: Y10S 707/99945 Object-oriented database structure processing
• CPC Class Codes: Y10S 707/99948 Application of database or data structure, e.g. distributed, multimedia, or image
• CPC Class Codes: Y10S 707/99953 Recoverability

Abstract

Storing audio data encoded in any of a plurality of different audio encoding formats is enabled by parametrically defining the underlying format in which the audio data is encoded, in audio format and packet table chunks. A flag can be used to manage storage of the size of the audio data portion of the file, such that premature termination of an audio recording session does not result in an unreadable corrupted file. This capability can be enabled by initially setting the flag to a value that does not correspond to a valid audio data size and that indicates that the last chunk in the file contains the audio data. State information for the audio data, to effectively denote a version of the file, and a dependency indicator for dependent metadata, may be maintained, where the dependency indicator indicates the state of the audio data on which the metadata is dependent.

Claims

1. A method for storing audio information, comprising:

storing, as part of an audio file,

audio data that represents an audio stream encoded in any one of a plurality of formats;

metadata information about said audio data;

wherein said metadata information includes information for identifying individual packets within said audio data, including

how many channels are in each sample frame; and

how many bits of sample data are for each channel in each sample frame.

2. The method of claim 1, wherein said metadata information further includes information that indicates:

how many sample frames per second are in said stream;

how many bytes are in each packet; and

how many sample frames are in each packet.

3. The method of claim 1, wherein:

said information about how many bytes are in each packet indicates that said audio data is encoded in a format, of said plurality of formats, that has a variable packet size; and

said metadata information further includes packet size information that indicates sizes for packets in said audio stream.

4. The method of claim 3, wherein said metadata information further includes:

metadata that indicates how many sample frames that said audio stream uses for priming or processing latency; and

metadata that indicates how many sample frames, in a last packet that contains actual audio data, in said audio stream follow a last sample frame of actual audio data.

5. The method of claim 1, wherein:

said information about how many sample frames are in each packet indicates that said audio data is encoded in a format, of said plurality of formats, that has a variable number of sample frames per packet; and

said metadata information further includes frame count information that indicates how many sample frames are in packets in said audio stream.

6. The method of claim 5, wherein said metadata information further includes:

metadata that indicates how many sample frames that said audio stream uses for priming or processing latency; and

metadata that indicates how many sample frames, in a last packet that contains actual audio data, in said audio stream follow a last sample frame of actual audio data.

7. The method of claim 1, further comprising:

sampling said audio stream to generate a set of statistics corresponding to data points in said audio stream; and

wherein said metadata information includes said set of statistics.

8. The method of claim 7, wherein said set of statistics includes a minimum amplitude and a maximum amplitude for each of said data points.

9. The method of claim 7, further comprising:

after said set of statistics has been stored in said audio file, reading said set of statistics from said audio file to generate a display of statistics associated with said audio stream.

10. The method of claim 7, wherein:

said set of statistics is one of a plurality of sets of statistics that are stored within said audio file; and

each set of statistics, of said plurality of sets of statistics, contains the same type of statistics, sampled at different resolutions.

11. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform:

storing, as part of an audio file,

audio data that represents an audio stream encoded in any one of a plurality of formats;

metadata information about said audio data;

wherein said metadata information includes information for identifying individual packets within said audio data, including

how many channels are in each sample frame; and

how many bits of sample data are for each channel in each sample frame.

12. The computer-readable medium of claim 11, wherein said metadata information further includes information that indicates:

how many sample frames per second are in said stream;

how many bytes are in each packet; and

how many sample frames are in each packet.

13. The computer-readable medium of claim 11, wherein:

said information about how many bytes are in each packet indicates that said audio data is encoded in a format, of said plurality of formats, that has a variable packet size; and

said metadata information further includes packet size information that indicates sizes for packets in said audio stream.

14. The computer-readable medium of claim 13, wherein said metadata information further includes:

metadata that indicates how many sample frames that said audio stream uses for priming or processing latency; and

metadata that indicates how many sample frames, in a last packet that contains actual audio data, in said audio stream follow a last sample frame of actual audio data.

15. The computer-readable medium of claim 11, wherein:

said information about how many sample frames are in each packet indicates that said audio data is encoded in a format, of said plurality of formats, that has a variable number of sample frames per packet; and

said metadata information further includes frame count information that indicates how many sample frames are in packets in said audio stream.

16. The computer-readable medium of claim 15, wherein said metadata information further includes:

metadata that indicates how many sample frames that said audio stream uses for priming or processing latency; and

metadata that indicates how many sample frames, in a last packet that contains actual audio data, in said audio stream follow a last sample frame of actual audio data.

17. The computer-readable medium of claim 11, wherein said one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform:

sampling said audio stream to generate a set of statistics corresponding to data points in said audio stream; and

wherein said metadata information includes said set of statistics.

18. The computer-readable medium of claim 17, wherein said set of statistics includes a minimum amplitude and a maximum amplitude for each of said data points.

19. The computer-readable medium of claim 17, wherein said one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform:

after said set of statistics has been stored in said audio file, reading said set of statistics from said audio file to generate a display of statistics associated with said audio stream.

20. The computer-readable medium of claim 17, wherein:

said set of statistics is one of a plurality of sets of statistics that are stored within said audio file; and

each set of statistics, of said plurality of sets of statistics, contains the same type of statistics, sampled at different resolutions.

21. A computer-readable medium storing an audio file, the audio file comprising:

a set of chunks that includes an audio data chunk and a plurality of metadata chunks;

wherein said audio data chunk includes one or more packets that correspond to a stream of encoded audio;

wherein each chunk of said set of chunks includes metadata indicating

a chunk version;

a chunk size; and

a chunk type;

wherein said set of chunks includes a format chunk that precedes said audio data chunk in said audio file, said format chunk including metadata indicating

a number of sample frames per second of said audio data in said stream;

data indicating the general kind of data in said stream;

how many bytes are in each packet of data;

how many sample frames are in each packet of data;

how many channels are in each frame of data;

how many bits of sample data are for each channel in a frame of data.

22. The computer-readable medium of claim 21, wherein said audio file further comprises:

state information for said stream; and

one or more dependency indicators associated with at least one of said plurality of metadata chunks.

23. The computer-readable medium of claim 21, wherein said audio file further comprises:

a field in a metadata chunk of said plurality of metadata chunks,

whose value acts as a flag while in a first state, to indicate that a last chunk in said audio file is said audio data chunk that contains said stream, and

whose value represents the size of said stream while in a second state that is different from said first state.

24. The computer-readable medium of claim 21, wherein said audio file further comprises:

a packet table chunk that includes

metadata that indicates how many sample frames that said stream uses for priming or processing latency; and

metadata that indicates how many sample frames, in a last packet that contains actual audio data, in said stream follow a last sample frame of actual audio data.

25. The computer-readable medium of claim 21, wherein said audio file further comprises:

a channel descriptions chunk that includes metadata information about each of one or more channels of encoded audio in said stream, wherein said metadata information describes a spatial layout of said one or more channels.