Parallel entropy coding

A computer program for entropy encoding data of a plurality of channels of a same size into a bitstream, stored on a non-transitory medium and including code instructions, which, when executed on one or more processors, cause the one or more processor to execute steps comprising:

• multiplexing portions of a first size from each of the channels of the plurality of channels, and encoding the multiplexed portions of the first size into a first substream:
• multiplexing portions of a second size from each of the channels of the plurality of channels, and subsequently encoding the multiplexed portions of the second size into a second substream:
• wherein
• the encoding is an entropy encoding performed independently into the first substream and into the second substream,
• wherein the entropy encoding is an arithmetic encoding.

An apparatus for entropy encoding data of a plurality of channels of a same size into a bitstream, comprising:

• processing circuitry configured to:
• multiplex portions of a first size from each of the channels of the plurality of channels, and subsequently encode the multiplexed portions of the first size into a first substream;
• multiplex portions of a second size from each of the channels of the plurality of channels, and subsequently encode the multiplexed portions of the second size into a second substream;
• wherein
• the encoding is an entropy encoding performed independently into the first substream and into the second substream,
• wherein the entropy encoding is an arithmetic encoding.

An apparatus for entropy decoding a bitstream into data of a plurality of channels of a same size, comprising:

• processing circuitry configured to:
• entropy decode a first substream independently from a second substream,
• demultiplex portions of a first size and portions of a second size from the first substream and the second substream into the plurality of channels of the same size,
• wherein the entropy decoding is an arithmetic decoding.