Rate-distortion optimal fast thresholding for MPEG-2 image sequence coding

A new Rate-Distortion (R-D) optimized image sequence encoding scheme is int roduced, fully compatible with the standard MPEG-2 decoder. R-D optimal DCT coefficient thresholding is used, so that best image reproduction quality is achieved under the constraint of a "local" target bit rate for every ima ge. The proposed technique combines R-D optimal coefficient thresholding an d some elements of the MPEG-2 rate control model "Test Model 5" and results in a new video encoding scheme, which offers in most cases a higher repres entation quality than "Test Model 5". The performance of the proposed techn ique is experimentally evaluated for the coding of standard test image sequ ences.