Codeword assignment for fixed-length entropy coded video streams

Abstract

Fixed length entropy codes (FLC) have been successfully employed as an alternative to the popular variable length codes (VLC) in video codecs. This paper presents a codeword assignment for FLC coded interframe coefficients and motion vectors that minimizes the effects of bit errors on the decoded video sequence. Intensive testing has shown that with the proposed solution, the distortion introduced by transmission errors is coarsely half of that obtained with VLC codes, while maintaining the compression efficiency.