Video game system using pre-encoded digital audio mixing

• US 20070105631A1
• Filed: 01/05/2007
• Published: 05/10/2007
• Est. Priority Date: 07/08/2005
• Status: Active Grant

• Current Assignee: ActiveVideo Networks, Inc. (CommScope Holding Company, Inc.)
• Original Assignee: ActiveVideo Networks, Inc. (CommScope Holding Company, Inc.)
• Inventors: Sigmund, Ulrich, Herr, Stefan
• Granted Patent: US 8,270,439 B2
• Time in Patent Office: Days
• US Class Current: 463/42
• CPC Class Codes: G07F 17/32 for games, toys, sports, or amusements
• CPC Class Codes: G10L 19/008 Multichannel audio signal coding or decoding using interchannel correlation to reduce redundancy, e.g. joint-stereo, intensity-coding or matrixing
• CPC Class Codes: G10L 19/032 Quantisation or dequantisation of spectral components
• CPC Class Codes: G10L 19/24 Variable rate codecs, e.g. for generating different qualities using a scalable representation such as hierarchical encoding or layered encoding
• CPC Class Codes: H04S 2420/03 Application of parametric coding in stereophonic audio systems
• CPC Class Codes: H04S 3/008 in which the audio signals are in digital form, i.e. employing more than two discrete digital channels data reduction aspects thereof based on psychoacoustics G10L19/02

Abstract

A method and related system of encoding audio is disclosed. In the method, data representing a plurality of independent audio signals is accessed. The data representing each respective audio signal comprises a sequence of source frames. Each frame in the sequence of sources frames comprises a plurality of audio data copies. Each audio data copy has an associated quality level that is a member of a predefined range of quality levels, ranging from a highest quality level to a lowest quality level. The plurality of source frame sequences is merged into a sequence of target frames that comprise a plurality of target channels. Merging corresponding source frames into a respective target frame includes selecting a quality level and assigning the audio data copy at the selected quality level of each corresponding source frame to at least one respective target channel.

Claims

1. A method of encoding audio, comprising:

accessing data representing a plurality of independent audio signals, the data representing each respective audio signal comprising a sequence of source frames;

wherein each frame in the sequence of sources frames comprises a plurality of audio data copies, each audio data copy having an associated quality level, the quality level of each copy being a member of a predefined range of quality levels that range from a highest quality level to a lowest quality level; and

merging the plurality of source frame sequences into a sequence of target frames, wherein the target frames comprise a plurality of target channels, the merging including, for a respective target frame and corresponding source frames, selecting a quality level and assigning the audio data copy at the selected quality level of each corresponding source frame to at least one respective target channel.

2. The method of claim 1, wherein a respective audio data copy comprises one or more fractional mantissa groups, wherein each fractional mantissa group is full.

3. The method of claim 1, wherein a first one of the accessed source frame sequences comprises a continuous source of non-silent audio data and a second one of the accessed source frame sequences comprises an episodic source of non-silent audio data that includes sequences of audio data representing silence.

4. The method of claim 1, wherein a first one of the accessed source frame sequences comprises a first episodic source of non-silent audio data that includes sequences of audio data representing silence and a second one of the accessed source frame sequences comprises a second episodic source of non-silent audio data that includes sequences of audio data representing silence.

5. The method of claim 1, wherein a first one of the accessed source frame sequences comprises a first continuous source of non-silent audio data and a second one of the accessed source frame sequences comprises a second continuous source of non-silent audio data.

6. A method of encoding audio, comprising:

receiving audio data from a plurality of respective independent sources;

encoding the audio data from each respective independent source into a sequence of source frames, to produce a plurality of source frame sequences; and

merging the plurality of source frame sequences into a sequence of target frames, wherein the target frames comprise a plurality of independent target channels and each source frame sequence is uniquely assigned to one or more target channels of the plurality of independent target channels.

7. The method of claim 6, further comprising:

receiving a command, and

transmitting the sequence of target frames.

8. The method of claim 6, wherein the audio data from a respective independent source is a pulse-code-modulated bitstream.

9. The method of claim 8, wherein the pulse-code-modulated bitstream is a WAV, W64, AU, or AIFF file.

10. The method of claim 6, wherein encoding the audio data comprises:

for a frame in the sequence of sources frames, generating a plurality of copies of the frame, each copy having an associated quality level, the quality level of each copy being a member of a predefined range of quality levels that range from a highest quality level to a lowest quality level.

11. The method of claim 10, wherein encoding the audio data further comprises:

for each copy, performing a bit allocation process; and

if the bit allocation process creates one or more incomplete fractional mantissa groups, modifying results of the bit allocation process to either fill or empty each incomplete fractional mantissa group.

12. The method of claim 11, wherein results of the bit allocation process are modified by performing delta bit allocation.

13. The method of claim 12, wherein the performed delta bit allocation is determined by a backtracking algorithm.

14. The method of claim 11, wherein for a respective copy, if each incomplete fractional mantissa group cannot be either filled or emptied, the respective copy is not included in the frame.

15. The method of claim 10, wherein the associated quality levels correspond to specified signal-to-noise ratios.

16. The method of claim 11, wherein merging the plurality of source frames sequences into the sequence of target frames comprises:

selecting a signal-to-noise ratio for a source frame; and

merging the copy having the selected signal-to-noise ratio into a target frame in the sequence of target frames.

17. The method of claim 16, wherein the signal-to-noise ratio is selected to maintain a constant bit rate for the sequence of target frames.

18. The method of claim 6, wherein the target frames are in the AC-3 format.

19. A method of playing audio in conjunction with a speaker system, comprising:

in response to a command, receiving audio data comprising a sequence of frames containing a plurality of channels wherein each channel in the plurality of channels either (A) corresponds solely to an independent audio source, or (B) corresponds solely to a unique channel in an independent audio source;

if the number of speakers is less than the number of channels, down-mixing two or more channels and playing the audio data associated with the two or more down-mixed channels on a single speaker; and

if the number of speakers is equal to or greater than the number of channels, playing the audio data associated with each channel on a corresponding speaker.

20. The method of claim 19, wherein the received audio data is in the AC-3 format.

21. A system for encoding audio, comprising:

memory;

one or more processors;

one or more programs stored in the memory and configured for execution by the one or more processors, the one or more programs including;

instructions for accessing data representing a plurality of independent audio signals, the data representing each respective audio signal comprising a sequence of source frames;

wherein each frame in the sequence of sources frames comprises a plurality of audio data copies, each audio data copy having an associated quality level, the quality level of each copy being a member of a predefined range of quality levels that range from a highest quality level to a lowest quality level; and

instructions for merging the plurality of source frame sequences into a sequence of target frames, wherein the target frames comprise a plurality of target channels, the instructions for merging including, for a respective target frame and corresponding source frames, instructions for selecting a quality level and instructions for assigning the audio data copy at the selected quality level of each corresponding source frame to at least one respective target channel.

22. A system for encoding audio, comprising:

memory;

one or more processors;

one or more programs stored in the memory and configured for execution by the one or more processors, the one or more programs including;

instructions for receiving audio data from a plurality of respective independent sources;

instructions for encoding the audio data from each respective independent source into a sequence of source frames, to produce a plurality of source frame sequences; and

instructions for merging the plurality of source frame sequences into a sequence of target frames, wherein the target frames comprise a plurality of independent target channels and each source frame sequence is uniquely assigned to one or more target channels of the plurality of independent target channels.

23. A system for playing audio in conjunction with a speaker system, comprising:

memory;

one or more processors;

one or more programs stored in the memory and configured for execution by the one or more processors, the one or more programs including;

instructions for receiving, in response to a command, audio data comprising a sequence of frames containing a plurality of channels wherein each channel in the plurality of channels either (A) corresponds solely to an independent audio source, or (B) corresponds solely to a unique channel in an independent audio source;

instructions for down-mixing two or more channels and playing the audio data associated with the two or more down-mixed channels on a single speaker if the number of speakers is less than the number of channels; and

instructions for playing the audio data associated with each channel on a corresponding speaker if the number of speakers is equal to or greater than the number of channels.

24. A computer program product for use in conjunction with audio encoding, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism comprising:

instructions for accessing data representing a plurality of independent audio signals, the data representing each respective audio signal comprising a sequence of source frames;

wherein each frame in the sequence of sources frames comprises a plurality of audio data copies, each audio data copy having an associated quality level, the quality level of each copy being a member of a predefined range of quality levels that range from a highest quality level to a lowest quality level; and

instructions for merging the plurality of source frame sequences into a sequence of target frames, wherein the target frames comprise a plurality of target channels, the instructions for merging including, for a respective target frame and corresponding source frames, instructions for selecting a quality level and instructions for assigning the audio data copy at the selected quality level of each corresponding source frame to at least one respective target channel.

25. A computer program product for use in conjunction with audio encoding, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism comprising:

instructions for receiving audio data from a plurality of respective independent sources;

instructions for encoding the audio data from each respective independent source into a sequence of source frames, to produce a plurality of source frame sequences; and

instructions for merging the plurality of source frame sequences into a sequence of target frames, wherein the target frames comprise a plurality of independent target channels and each source frame sequence is uniquely assigned to one or more target channels of the plurality of independent target channels.

26. A computer program product for use in conjunction with playing audio on a speaker system, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism comprising:

instructions for receiving, in response to a command, audio data comprising a sequence of frames containing a plurality of channels wherein each channel in the plurality of channels either (A) corresponds solely to an independent audio source, or (B) corresponds solely to a unique channel in an independent audio source;

instructions for down-mixing two or more channels and playing the audio data associated with the two or more down-mixed channels on a single speaker if the number of speakers is less than the number of channels; and

instructions for playing the audio data associated with each channel on a corresponding speaker if the number of speakers is equal to or greater than the number of channels.

27. A system for encoding audio, comprising:

means for accessing data representing a plurality of independent audio signals, the data representing each respective audio signal comprising a sequence of source frames;

wherein each frame in the sequence of sources frames comprises a plurality of audio data copies, each audio data copy having an associated quality level, the quality level of each copy being a member of a predefined range of quality levels that range from a highest quality level to a lowest quality level; and

means for merging the plurality of source frame sequences into a sequence of target frames, wherein the target frames comprise a plurality of target channels, the means for merging including, for a respective target frame and corresponding source frames, means for selecting a quality level and means for assigning the audio data copy at the selected quality level of each corresponding source frame to at least one respective target channel.

28. A system for encoding audio, comprising:

means for receiving audio data from a plurality of respective independent sources;

means for encoding the audio data from each respective independent source into a sequence of source frames, to produce a plurality of source frame sequences; and

means for merging the plurality of source frame sequences into a sequence of target frames, wherein the target frames comprise a plurality of independent target channels and each source frame sequence is uniquely assigned to one or more target channels of the plurality of independent target channels.

29. A system for playing audio in conjunction with a speaker system, comprising:

means for receiving, in response to a command, audio data comprising a sequence of frames containing a plurality of channels wherein each channel in the plurality of channels either (A) corresponds solely to an independent audio source, or (B) corresponds solely to a unique channel in an independent audio source;

means for down-mixing two or more channels and playing the audio data associated with the two or more down-mixed channels on a single speaker if the number of speakers is less than the number of channels; and

means for playing the audio data associated with each channel on a corresponding speaker if the number of speakers is equal to or greater than the number of channels.