Data multiplexing apparatus

Abstract

A data processing apparatus (and method of data processing) that creates a plurality of audio packs from audio streams including a plurality of audio frames, includes an audio buffer occupancy calculator that calculates an occupancy of an audio buffer for temporarily storing the audio streams, and a payload length setting section that defines a predetermined overflow limit capacity for the audio buffer, and that determines a payload length of each of the audio packs based on a difference between the overflow limit capacity and the occupancy.

1 . A data processing apparatus that creates a plurality of audio packs from audio streams including a plurality of audio frames, the data processing apparatus comprising:
 an audio buffer occupancy calculator that calculates an occupancy of an audio buffer for temporarily storing the audio streams; and   a payload length setting section that defines a predetermined overflow limit capacity for the audio buffer, and that determines a payload length of each of the audio packs based on a difference between the overflow limit capacity and the occupancy.   
     
     
         2 . The data processing apparatus according to  claim 1 , wherein the overflow limit capacity is set to a value of an integral multiple of a length of one of the audio frames. 
     
     
         3 . The data processing apparatus according to  claim 1 , wherein the payload length is a sum of lengths of audio streams included in one of the audio packs. 
     
     
         4 . The data processing apparatus according to  claim 1 , further comprising:
 a multiplexing data creating section,   wherein the multiplexing data creating section creates an audio pack of the plurality of audio packs when the difference between the overflow limit capacity and the occupancy is larger than the determined payload length.   
     
     
         5 . The data processing apparatus according to  claim 4 , wherein the multiplexing data creating section determines a type of pack to be multiplexed, a length of a stream and a timing of multiplexing, based on the occupancy of the audio buffer. 
     
     
         6 . The data processing apparatus according to  claim 1 , wherein at a time just before a random access point, if a sum of a length of an un-multiplexed frame that is not included in the created audio pack among one of the audio frames and the occupancy of the audio buffer is less than the overflow limit capacity, the payload length is set to a value that is equal to a sum of the length of the un-multiplexed frame and an N-th length of the audio frame (N is an integer of zero or above), and that does not exceed the overflow limit capacity. 
     
     
         7 . A data processing method of creating a plurality of audio packs from audio streams including a plurality of audio frames, the method comprising:
 defining a predetermined overflow limit capacity for an audio buffer temporarily storing the audio streams; and   setting, not at a time just before a random access point, a payload length of the audio pack to a maximum payload length that is capable of being included in the audio pack if a sum of an occupancy of the audio buffer and the maximum payload length does not exceed the overflow limit capacity.   
     
     
         8 . The data processing method according to  claim 7 , further comprising:
 setting, at the time just before the random access point, the payload length to a value that is equal to a sum of a length of an un-multiplexed frame that is not included in the created audio pack among one of the audio frames and an N-th length of the audio frame (N is an integer of zero or above), and that does not exceed the overflow limit capacity, if a sum of the length of the un-multiplexed frame and the occupancy is less than the overflow limit capacity.