VQ-BCTCQ를 이용한 광대역 음성부호화기용 LSF 계수 양자화기 설계에 관한 연구

Abstract

In this paper, we propose the vector quantization-block constrained trellis coded quantization (VQ-BCTCQ) and block constrained trellis coded vector quantization (BC-TCVQ) . VQ- BCTCQ is presented to quantize the LPC parameter of wideband speech codec. The first stage of VQ-BCTCQ is the unstructured vector quantizer (VQ) and second stage is the block constrained trellis coded quantization (BCTCQ). Also both predictive structure and safety-net concept are combined into VQ-BCTCQ to develop the predictive VQ-BCTCQ. The performance of this quantization is compared with that of the linear predictive coding (LPC) vector quantizer used in the AMR-WB codec, and reductions in spectral distortion (SD) and encoding complexity are demonstrated BC-TCVQ is also presented to quantize line spectrum frequency (LSF) parameters of the wideband speech codec. Both the predictive structure and safety-net concept are combined into BC-TCVQ to develop the predictive BC-TCVQ. The performance of this quantization is compared with that of the linear predictive coding (LPC) vector quantizer used in the AMR-WB codec, and reductions in spectral distortion (SD) and encoding complexity are demonstrated.