Audio encoder and decoder with program information or substream structure metadata

Patent metadata

Field	Value
Publication number	US-2016196830-A1
Application number	US-201414770375-A
Country	US
Kind code	A1
Filing date	Jun 12, 2014
Priority date	Jun 19, 2013
Publication date	Jul 7, 2016
Grant date	—

Abstract

Apparatus and methods for generating an encoded audio bitstream, including by including substream structure metadata (SSM) and/or program information metadata (PIM) and audio data in the bitstream. Other aspects are apparatus and methods for decoding such a bitstream, and an audio processing unit (e.g., an encoder, decoder, or post-processor) configured (e.g., programmed) to perform any embodiment of the method or which includes a buffer memory which stores at least one frame of an audio bitstream generated in accordance with any embodiment of the method.

First claim

What is claimed is:

1 . An audio processing unit, including:
a buffer memory; and at least one processing subsystem coupled to the buffer memory, wherein the buffer memory stores at least one frame of an encoded audio bitstream, said frame including program information metadata or substream structure metadata in at least one metadata segment of at least one skip field of the frame and audio data in at least one other segment of the frame, wherein the processing subsystem is coupled and configured to perform at least one of generation of the bitstream, decoding of the bitstream, or adaptive processing of audio data of the bitstream using metadata of the bitstream, or at least one of authentication or validation of at least one of audio data or metadata of the bitstream using metadata of the bitstream, wherein the metadata segment includes at least one metadata payload, said metadata payload comprising: a header; and after the header, at least some of the program information metadata or at least some of the substream structure metadata.

2 . The audio processing unit of claim 1 , wherein the encoded audio bitstream is indicative of at least one audio program, and the metadata segment includes a program information metadata payload, said program information metadata payload comprising:
a program information metadata header; and after the program information metadata header, program information metadata indicative of at least one property or characteristic of audio content of the program, said program information metadata including active channel metadata indicative of each non-silent channel and each silent channel of the program.

3 . The audio processing unit of claim 2 , wherein the program information metadata also includes at least one of:
downmix processing state metadata indicative of whether the program was downmixed, and if so, a type of downmixing that was applied to the program; upmix processing state metadata indicative of whether the program was upmixed, and if so, a type of upmixing that was applied to the program; preprocessing state metadata indicative of whether preprocessing was performed on audio content of the frame, and if so, a type of preprocessing that was performed on said audio content; or spectral extension processing or channel coupling metadata indicative of whether spectral extension processing or channel coupling was applied to the program, and if so, a frequency range that the spectral extension or channel coupling was applied.

4 . The audio processing unit of claim 1 , wherein the encoded audio bitstream is indicative of at least one audio program having at least one independent substream of audio content, and the metadata segment includes a substream structure metadata payload, said substream structure metadata payload comprising:
a substream structure metadata payload header; and after the substream structure metadata payload header, independent substream metadata indicative of number of independent substreams of the program, and dependent substream metadata indicative of whether each independent substream of the program has at least one associated dependent substream.

5 . The audio processing unit of claim 1 , wherein the metadata segment includes:
a metadata segment header; after the metadata segment header, at least one protection value useful for at least one of decryption, authentication, or validation of at least one of the program information metadata or the substream structure metadata or the audio data corresponding to said program information metadata or said substream structure metadata; and after the metadata segment header, metadata payload identification and payload configuration values, wherein the metadata payload follows the metadata payload identification and payload configuration values.

6 . The audio processing unit of claim 5 , wherein the metadata segment header includes a syncword identifying the start of the metadata segment, and at least one identification value following the syncword, and the header of the metadata payload includes at least one identification value.

7 . The audio processing unit of claim 1 , wherein the encoded audio bitstream is an AC-3 bitstream or an E-AC-3 bitstream.

8 . The audio processing unit of claim 1 , wherein the buffer memory stores the frame in a non-transitory manner.

9 . The audio processing unit of claim 1 , wherein the audio processing unit is an encoder.

10 . The the audio processing unit of claim 9 , wherein said processing subsystem includes:
a decoding subsystem configured to receive an input audio bitstream and to extract input metadata and input audio data from the input audio bitstream; an adaptive processing subsystem coupled and configured to perform adaptive processing on the input audio data using the input metadata, thereby generating processed audio data; and an encoding subsystem coupled and configured to generate the encoded audio bitstream in response to the processed audio data, including by including the program information metadata or the substream structure metadata in said encoded audio bitstream, and to assert the encoded audio bitstream to the buffer memory.

11 . The audio processing unit of claim 1 , wherein the audio processing unit is a decoder.

12 . The the audio processing unit of claim 11 , wherein the processing subsystem is a decoding subsystem coupled to the buffer memory and configured to extract the program information metadata or the substream structure metadata from the encoded audio bitstream.

13 . The audio processing unit of claim 1 , including:
a subsystem coupled to the buffer memory and configured to extract the program information metadata or the substream structure metadata from the encoded audio bitstream and to extract the audio data from the encoded audio bitstream; and a post-processor, coupled to the subsystem and configured to perform adaptive processing on the audio data using at least one of the program information metadata or the substream structure metadata extracted from the encoded audio bitstream.

14 . The audio processing unit of claim 1 , wherein said audio processing unit is a digital signal processor.

15 . The audio processing unit of claim 1 , wherein the audio processing unit is a pre-processor configured to extract the program information metadata or the substream structure metadata and the audio data from the encoded audio bitstream, and to perform adaptive processing on the audio data using at least one of the program information metadata or the substream structure metadata extracted from the encoded audio bitstream.

16 . A method for decoding an encoded audio bitstream, said method including steps of:
receiving an encoded audio bitstream; and extracting metadata and audio data from the encoded audio bitstream, wherein the metadata is or includes program information metadata and substream structure metadata, wherein the encoded audio bitstream comprises a sequence of frames and is indicative of at least one audio program, the program information metadata and the substream structure metadata are indicative of the program, each of the frames includes at least one audio data segment, each said audio data segment includes at least some of the audio data, each frame of at least a subset of the frames includes a metadata segment, and each said metadata segment includes at least some of the program information metadata and at least some of the substream structure metadata.

17 . The method of claim 16 , wherein the metadata segment includes a program information metadata

Assignees

• Dolby Lab Licensing Corp

Inventors

• Riedmiller Jeffrey
• Ward Michael

Classifications

• G10L21/0316

  by changing the amplitude · CPC title

• G10L19/26

  Pre-filtering or post-filtering · CPC title

• G10L19/16

  Vocoder architecture · CPC title

• H04S3/00

  Systems employing more than two channels, e.g. quadraphonic (H04S5/00, H04S7/00 take precedence) · CPC title

• G10L19/167 Primary

  Audio streaming, i.e. formatting and decoding of an encoded audio signal representation into a data stream for transmission or storage purposes · CPC title