Integer Multiple Description Coding System

Abstract

A method for decoding multiple descriptions for a media stream includes decoding at least one of a first description and a second description from the media bitstream, wherein the first description and the second description are associated with a current sample of the media bitstream and independently decodable; based on a determination that the second description is missing, reconstructing, by a decoder, the current sample by performing a third shifting operation on the first description, wherein the third shifting operation on the first description comprises left shifting the first description by one bit; and based on a determination that both the first description and the second description have been received, reconstructing, by the decoder, the current sample by summing the first description and the second description. An encoding method is also provided.

What is claimed is: 
     
         1 . An apparatus for decoding multiple descriptions for a media bitstream, comprising:
 a processor; and   a memory coupled to the processor, the memory configured to store instructions which when executed by the processor become operational with the processor to:
 decode, for a current sample and from the media bitstream, a multiple description number indicative of a total number of descriptions encoded for the current sample; 
 based on a determination that the total number of descriptions received by a decoder is less than the multiple description number, reconstruct the current sample by performing a lookup operation on the descriptions received by the decoder, wherein the lookup operation comprises obtaining an estimation of the current sample by using a lookup table based on at least one of the multiple description number and the descriptions received by the decoder; and 
 based on a determination that the total number of descriptions received by the decoder is the same as the multiple description number, reconstruct the current sample by summing the descriptions received by the decoder. 
   
     
     
         2 . The apparatus of  claim 1 , wherein at least one of the descriptions is determined by performing a shifting operation on the current sample, wherein the shifting operation comprises right shifting the current sample by one bit. 
     
     
         3 . The apparatus of  claim 1 , wherein the instructions to based on the determination that the total number of descriptions received by the decoder is less than the multiple description number, reconstruct the current sample by performing the lookup operation on the descriptions received by the decoder, wherein the lookup operation comprises obtaining an estimation of the current sample by using a lookup table based on at least one of the multiple description number and the descriptions received by the decoder comprise instructions to:
 select, based on the descriptions received by the decoder, the lookup table from multiple lookup tables, wherein the multiple lookup tables are predetermined based on the multiple description number and each possible combination of the descriptions received by the decoder.   
     
     
         4 . The apparatus of  claim 1 , wherein the estimation of the current sample is obtained from the lookup table by using an average of possible missing descriptions for the current sample. 
     
     
         5 . The apparatus of  claim 1 , wherein the media bitstream comprises at least one of an audio bitstream and a video bitstream. 
     
     
         6 . A method for decoding multiple descriptions for a media bitstream, comprising:
 decoding, for a current sample and from the media bitstream, a multiple description number indicative of a total number of descriptions encoded for the current sample;   based on a determination that the total number of descriptions received by a decoder is less than the multiple description number, reconstructing the current sample by performing a lookup operation on the descriptions received by the decoder, wherein the lookup operation comprises obtaining an estimation of the current sample by using a lookup table based on at least one of the multiple description number and the descriptions received by the decoder; and   based on a determination that the total number of descriptions received by the decoder is the same as the multiple description number, reconstructing the current sample by summing the descriptions received by the decoder.   
     
     
         7 . The method of  claim 6 , wherein at least one of the descriptions is determined by performing a shifting operation on the current sample, wherein the shifting operation comprises right shifting the current sample by one bit. 
     
     
         8 . The method of  claim 6 , wherein based on the determination that the total number of descriptions received by the decoder is less than the multiple description number, reconstructing the current sample by performing the lookup operation on the descriptions received by the decoder, wherein the lookup operation comprises obtaining an estimation of the current sample by using a lookup table based on at least one of the multiple description number and the descriptions received by the decoder comprises:
 selecting, based on the descriptions received by the decoder, the lookup table from multiple lookup tables, wherein the multiple lookup tables are predetermined based on the multiple description number and each possible combination of the descriptions received by the decoder.   
     
     
         9 . The method of  claim 6 , wherein the estimation of the current sample is obtained from the lookup table by using an average of possible missing descriptions for the current sample. 
     
     
         10 . The method of  claim 6 , wherein the media bitstream comprises at least one of an audio bitstream and a video bitstream.