Decoding audio bitstreams with enhanced spectral band replication metadata in at least one fill element

Patent metadata

Field	Value
Publication number	US-10134413-B2
Application number	US-201615546637-A
Country	US
Kind code	B2
Filing date	Mar 10, 2016
Priority date	Mar 13, 2015
Publication date	Nov 20, 2018
Grant date	Nov 20, 2018

Abstract

Embodiments relate to an audio processing unit that includes a buffer, bitstream payload deformatter, and a decoding subsystem. The buffer stores at least one block of an encoded audio bitstream. The block includes a fill element that begins with an identifier followed by fill data. The fill data includes at least one flag identifying whether enhanced spectral band replication (eSBR) processing is to be performed on audio content of the block. A corresponding method for decoding an encoded audio bitstream is also provided.

First claim

The invention claimed is:

1. An audio processing unit comprising:
a buffer configured to store at least one block of an encoded audio bitstream;
a bitstream payload deformatter coupled to the buffer and configured to demultiplex at least a portion of the at least one block of the encoded audio bitstream; and
a decoding subsystem coupled to the bitstream payload deformatter and configured to decode at least a portion of the at least one block of the encoded audio bitstream, wherein the at least one block of the encoded audio bitstream includes:
a fill element with an identifier indicating a start of the fill element and fill data after the identifier, wherein the fill data includes:
at least one flag identifying whether a base form of spectral band replication or an enhanced form of spectral band replication is to be performed on audio content of the at least one block of the encoded audio bitstream, wherein the base form of spectral band replication includes spectral patching, the enhanced form of spectral band replication includes harmonic transposition, one value of the flag indicates that said enhanced form of spectral band replication should be performed on the audio content, and another value of the flag indicates that said base form of spectral band replication but not said harmonic transposition should be performed on the audio content.

2. The audio processing unit of claim 1 wherein the fill data further includes enhanced spectral band replication metadata.

3. The audio processing unit of claim 2 wherein the enhanced spectral band replication metadata are contained in an extension payload of a fill element.

4. The audio processing unit of claim 2 wherein the enhanced spectral band replication metadata include one or more parameters defining a master frequency band table.

5. The audio processing unit of claim 2 wherein the enhanced spectral band replication metadata include envelope scalefactors or noise floor scalefactors.

6. A method for decoding an encoded audio bitstream, the method comprising:
receiving at least one block of an encoded audio bitstream;
demultiplexing at least a portion of the at least one block of the encoded audio bitstream; and
decoding at least a portion of at least one block of the audio bitstream,
wherein the at least one block of the encoded audio bitstream includes:
a fill element with an identifier indicating a start of the fill element and fill data after the identifier, wherein the fill data includes:
at least one flag identifying whether a base form of spectral band replication or an enhanced form of spectral band replication is to be performed on audio content of the at least one block of the encoded audio bitstream, wherein the base form of spectral band replication includes spectral patching, the enhanced form of spectral band replication includes harmonic transposition, one value of the flag indicates that said enhanced form of spectral band replication should be performed on the audio content, and another value of the flag indicates that said base form of spectral band replication but not said harmonic transposition should be performed on the audio content.

7. The method of claim 6 wherein the identifier is a three bit unsigned integer transmitted most significant bit first and having a value of 0x6.

8. The method of claim 6 wherein the fill data further includes enhanced spectral band replication metadata.

Assignees

• Dolby Int Ab

Inventors

• Villemoes Lars
• Purnhagen Heiko
• Ekstrand Per

Classifications

• G10L19/035

  Scalar quantisation · CPC title

• G10L19/24 Primary

  Variable rate codecs, e.g. for generating different qualities using a scalable representation such as hierarchical encoding or layered encoding · 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

• G10L21/038

  using band spreading techniques · CPC title

• G10L19/16

  Vocoder architecture · CPC title