Wavelet-based video coder via bit allocation

We present a video coder based on a bit-allocation (BA) scheme for a coding approach where a wavelet-based video compression scheme is used to encode group of frames (GOF), The proposed new BA method utilizes a Lagrangian mul tiplier technique to determine the optimal bit rate for each frame of a giv en GOF in a rate versus weighted distortion sense. The proposed baseline co der sequentially employs the application of the wavelet transform on each f rame in the group. In the wavelet domain, an optimal-vector BA (rate-alloca tion strategy) is being used to distribute the bit budget among the frames. The manipulated frames in each group are quantized and coded using techniq ues from still-image compression, We describe and demonstrate the performan ce of the proposed algorithm in wavelet-based coding approaches, The first one, a combination of wavelet still compression and optimal BA (WCBA), is b ased on frame differences and exploits well the wavelet compression charact eristics which keeps, for a given bit budget, the most important features. It does not utilize motion-compensation interpolation or a 3-D wavelet deco mposition. In cases where "heavy" motion is detected, we extend WCBA into a combination of wavelet still compression, optimal BA, motion compensation with block matching, and error correction (WCBAM), which uses block matchin g for motion estimation, while the residual error of the compression is red uced by applying error correction in the wavelet domain to reduce temporal redundancies.