tailieunhanh - Báo cáo hóa học: "Research Article Multiple-Description Multistage Vector Quantization"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Multiple-Description Multistage Vector Quantization | Hindawi Publishing Corporation EURASIP Journal on Audio Speech and Music Processing Volume 2007 Article ID 67146 7 pages doi 2007 67146 Research Article Multiple-Description Multistage Vector Quantization Pradeepa Yahampath Department of Electrical and Computer Engineering University of Manitoba Winnipeg Manitoba Canada R3T 5V6 Received 19 May 2007 Accepted 31 October 2007 Recommended by D. Wang Multistage vector quantization MSVQ is a technique for low complexity implementation of high-dimensional quantizers which has found applications within speech audio and image coding. In this paper a multiple-description MSVQ MD-MSVQ targeted for communication over packet-loss channels is proposed and investigated. An MD-MSVQ can be viewed as a generalization of a previously reported interleaving-based transmission scheme for multistage quantizers. An algorithm for optimizing the codebooks of an MD-MSVQ for a given packet-loss probability is suggested and a practical example involving quantization of speech line spectral frequency LSF vectors is presented to demonstrate the potential advantage of MD-MSVQ over interleaving-based MSVQ as well as traditional MSVQ based on error concealment at the receiver. Copyright 2007 Pradeepa Yahampath. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. INTRODUCTION Multiple-description MD quantization 1 2 has received considerable attention in recent research due to its potential applications in lossy communication systems such as packet networks. In order to achieve robustness against channel losses an MD quantizer assigns two or more codewords to be transmitted on separate packets for each input sample or more generally a vector of parameters representing a frame of samples in such a manner that the source input can be reconstructed with acceptable quality using any .