Video Coding using Entropy - ConstrainedTrellis Coded

Subband coding is becoming a viable compression method for video transmission, since the subband system can be eeciently split into a base layer and an enhancement layer without incurring any overhead. This is desirable in ATM and other packet networks. The base layer can be a standard coding algorithm such as H.261 or MPEG. In a subband-based video coding system, the higher-frequency subbands contain a small amount of the signal energy, but a large fraction of the subband data. Coarsely quantizing this higher-frequency information can achieve the desired bit rate, but will lead to lower resolution since the high frequency edges are perceptually important. In this paper, methods are studied to minimize the distortion of the coarsely coded higher frequency subbands through the use of Entropy-Constrained Trellis Coded Quantization (ECTCQ) and Entropy-Constrained Vector Quantization (ECVQ).