MPEG-2/ECVQ lookahead hybrid quantization and spatially scalable coding

In this paper, a nonlinear approach to spatially scalable coding is developed. Within the context of the MPEG-2 scalable syntax, various decimation and prediction schemes are discussed for the interlaced and progressive format video processing. A novel spatio-temporal video interpolation technique is presented, which is used as the basic unit in the prediction schemes. In addition to the considered scalability techniques, a lookahead quantization scheme is introduced for P- and B-type picture coding. The new quantization scheme results in further performance improvement by selective combination of the DCT domain scalar quantization and the spatial domain entropy-constrained vector quantization. The performance of the proposed scalable scheme is compared with that of the simulcast technique and the single layer coding. Remarkable performance improvement over the simulcast coding is achieved. While spatial scalability involves multi-layer coding, the new scalable scheme also achieves comparable or better performance than the single layer coding.