Patent ID: 6292512
Filing Date: 2001-09-18
Classification: H04N

Abstract:
A method of coding video data comprised of one or more frames, the method comprising:a first coding step for producing coded video data by coding a portion of the video data using a frame-prediction coding technique;a generating step for generating residual images based on the video data and the coded video data;a second coding step for producing coded residual images by coding the residual images using a fine-granular scalability coding technique; andan outputting step for outputting the coded video data and one or more of the coded residual images to a receiver;wherein the first coding step comprises coding the portion of the video data at a plurality of different bit rates so as to produce multiple versions of the coded video data;wherein the generating step comprises generating a plurality of residual images for each version of the coded video data;wherein the second coding step comprises coding the plurality of residual images for each version of the coded video data using a fine-granular scalability coding technique; andwherein the outputting step comprises outputting one version of the coded video data together with at least one corresponding coded residual image therefor;wherein the outputting step comprises the steps of:determining variations in a bandwidth of the receiver over time; andselecting which one of the multiple-versions of the coded video data and which of the coded residual images to output over time based on the variations in the bandwidth of the receiver;wherein, for a receiver bandwidth increasing from B.sub.1 to B.sub.2, where B.sub.1 <B.sub.2, the selecting step selects a first version of the coded video data and successively selects coded residual images corresponding to each frame of the first version of the coded video data, which are coded at successively higher bit rates; andwherein for a receiver bandwidth increasing from B.sub.2 to B.sub.3, where B.sub.2 <B.sub.3, the selecting step selects a second version of the coded video data and successively selects coded residual images corresponding to each frame of the second version of the coded video data, which are coded at successively higher bit rates.