Audio encoder and decoder with dynamic range compression metadata

Abstract

An audio processing unit (APU) is disclosed. The APU includes a buffer memory configured to store at least one frame of an encoded audio bitstream, where the encoded audio bitstream includes audio data and a metadata container. The metadata container includes a header and one or more metadata payloads after the header. The one or more metadata payloads include dynamic range compression (DRC) metadata, and the DRC metadata is or includes profile metadata indicative of whether the DRC metadata includes dynamic range compression (DRC) control values for use in performing dynamic range compression in accordance with at least one compression profile on audio content indicated by at least one block of the audio data.

What is claimed is: 
     
         1 . An audio processing method, comprising:
 receiving a block of encoded audio data;   receiving encoded audio metadata associated with the block of audio data;   performing a cryptographic hash on the audio metadata and on at least a portion of the audio data, to produce a currently-computed hash;   retrieving, from a data field associated with the encoded audio metadata, a previously-computed hash; and   performing an authentication process that involves comparing the currently-computed hash with the previously-computed hash.   
     
     
         2 . The audio processing method of  claim 1 , further comprising disabling or altering at least one operation to be performed on the audio data if the authentication process succeeds. 
     
     
         3 . The audio processing method of  claim 1 , wherein the metadata comprises dynamic range compression metadata. 
     
     
         4 . The audio processing method of  claim 1 , wherein the metadata comprises loudness processing state metadata. 
     
     
         5 . The audio processing method of  claim 1 , further comprising decoding at least a portion of the audio metadata or the audio data. 
     
     
         6 . A non-transitory medium having software stored thereon, the software including instructions for performing an audio processing method, the audio processing method comprising:
 receiving a block of encoded audio data;   receiving encoded audio metadata associated with the block of audio data;   performing a cryptographic hash on the audio metadata and on at least a portion of the audio data, to produce a currently-computed hash;   retrieving, from a data field associated with the encoded audio metadata, a previously-computed hash; and   performing an authentication process that involves comparing the currently-computed hash with the previously-computed hash.   
     
     
         7 . The non-transitory medium of  claim 6 , wherein the audio processing method further comprises disabling or altering at least one operation to be performed on the audio data if the authentication process succeeds. 
     
     
         8 . The non-transitory medium of  claim 6 , wherein the metadata comprises dynamic range compression metadata. 
     
     
         9 . The non-transitory medium of  claim 6 , wherein the metadata comprises loudness processing state metadata. 
     
     
         10 . The non-transitory medium of  claim 6 , wherein the audio processing method further comprises decoding at least a portion of the audio metadata or the audio data. 
     
     
         11 . An audio processing unit comprising at least one processor configured for:
 receiving a block of encoded audio data;   receiving encoded audio metadata associated with the block of audio data;   performing a cryptographic hash on the audio metadata and on at least a portion of the audio data, to produce a currently-computed hash;   retrieving, from a data field associated with the encoded audio metadata, a previously-computed hash; and   performing an authentication process that involves comparing the currently-computed hash with the previously-computed hash.   
     
     
         12 . The audio processing unit of  claim 11 , wherein the at least one processor is configured for disabling or altering at least one operation to be performed on the audio data if the authentication process succeeds. 
     
     
         13 . The audio processing unit of  claim 11 , wherein the metadata comprises dynamic range compression metadata. 
     
     
         14 . The audio processing unit of  claim 11 , wherein the metadata comprises loudness processing state metadata. 
     
     
         15 . The audio processing unit of  claim 11 , wherein the at least one processor is configured for decoding at least a portion of the audio metadata or the audio data. 
     
     
         16 . An audio processing unit, comprising:
 means for receiving a block of encoded audio data;   means for receiving encoded audio metadata associated with the block of audio data;   means for performing a cryptographic hash on the audio metadata and on at least a portion of the audio data, to produce a currently-computed hash;   means for retrieving, from a data field associated with the encoded audio metadata, a previously-computed hash; and   means for performing an authentication process that involves comparing the currently-computed hash with the previously-computed hash.   
     
     
         17 . The audio processing unit of  claim 16 , further comprising means for disabling or altering at least one operation to be performed on the audio data if the authentication process succeeds. 
     
     
         18 . The audio processing unit of  claim 16 , wherein the metadata comprises dynamic range compression metadata. 
     
     
         19 . The audio processing unit of  claim 16 , wherein the metadata comprises loudness processing state metadata. 
     
     
         20 . The audio processing unit of  claim 16 , further comprising means for decoding at least a portion of the audio metadata or the audio data.