Image sequence coding using wavelet transform

In MPEG, video compression is achieved by motion compensation, transformation, quantization and entropy coding. We follow the same path by using wavelet based modules in the coding chain. The prediction error signal is obtained by using variable block size motion compensation, and then, discrete wavelet transform (DWT) is applied to the prediction error signal to obtain wavelet coefficients. Some new schemes are introduced. First, a new and effective hybrid coder using quadtree and lattice vector quantization (QTLVQ) is introduced. Second, a new rate allocation scheme is introduced which can flexibly control the coder's output rate and the quality of reconstructed video signal.