Enhancing MPEG-4 CELP by jointly optimized inter/intra-frame LSP predictors

This paper presents an LSP quantization design method for bandwidth scalable coders such as the MPEG-4 CELP coder. In the enhancement layer of these coders, the LSP parameters are quantized using both interframe and intraframe predictors. The proposed design algorithm enables us to jointly optimize these predictors. Objective and subjective test results show that the quantizer obtained with the proposed algorithm provides better performance than that used in the MPEG-4 CELP.