Decoding of encoded audio bitstream with metadata container located in reserved data space

Abstract

Apparatus and methods for generating an encoded audio bitstream, including by including program loudness metadata and audio data in the bitstream, and optionally also program boundary metadata in at least one segment (e.g., frame) of the bitstream. Other aspects are apparatus and methods for decoding such a bitstream, e.g., including by performing adaptive loudness processing of the audio data of an audio program indicated by the bitstream, or authentication and/or validation of metadata and/or audio data of such an audio program. Another aspect is 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.

What is claimed is: 
     
         1 . An audio processing unit, comprising:
 a buffer memory configured to store an encoded audio bitstream, wherein the encoded audio bitstream contains audio data and metadata, wherein the metadata includes a payload of loudness metadata, wherein the payload of loudness metadata includes metadata indicative of a loudness of at least some of the audio data;   a parser coupled to the buffer memory and configured to extract the audio data and the payload of loudness metadata from the encoded audio bitstream;   a decoder coupled to the parser and configured to decode the audio data to generate decoded audio data; and   a subsystem coupled to the parser and the decoder and configured to perform post-processing on the decoded audio data in response to the metadata indicative of the loudness of at least some of the audio data.   
     
     
         2 . The audio processing unit of  claim 1 , wherein the metadata indicative of the loudness of at least some of the audio data includes metadata indicative of a measured loudness of an audio program. 
     
     
         3 . The audio processing unit of  claim 2 , wherein the payload of loudness metadata further includes an indication of a measurement method used to determine the measured loudness of the audio program. 
     
     
         4 . The audio processing unit of  claim 3 , wherein the measurement method is defined in ITU-R BS.1770. 
     
     
         5 . The audio processing unit of  claim 1 , wherein the metadata indicative of the loudness of at least some of the audio data includes metadata indicative of a short-term loudness of an audio program. 
     
     
         6 . The audio processing unit of  claim 5 , wherein the payload of loudness metadata further includes an indication of a measurement method used to determine the short-term loudness of the audio program. 
     
     
         7 . The audio processing unit of  claim 6 , wherein the measurement method is defined in ITU-R BS.1771. 
     
     
         8 . The audio processing unit of  claim 1 , wherein the payload of loudness metadata further includes an indication of a true peak sample value of an audio program. 
     
     
         9 . The audio processing unit of  claim 8 , wherein the payload of loudness metadata further includes an indication of a measurement method used to determine the true peak sample value of the audio program. 
     
     
         10 . The audio processing unit of  claim 9 , wherein the measurement method is defined in ITU-R BS.1770. 
     
     
         11 . An audio processing method, comprising steps of:
 receiving an encoded audio bitstream, wherein the encoded audio bitstream contains audio data and metadata, wherein the metadata includes a payload of loudness metadata, wherein the payload of loudness metadata includes metadata indicative of a loudness of at least some of the audio data;   extracting the audio data and the payload of loudness metadata from the encoded audio bitstream;   decoding the audio data to generate decoded audio data; and   performing post-processing on the decoded audio data in response to the metadata indicative of the loudness of at least some of the audio data.   
     
     
         12 . A computer-readable medium, which is a non-transitory medium, and on which is stored a computer program for causing one or more processors to perform the method of  claim 11 .