by Masayuki Nishiguchi and Bernd Edler
Keywords: CELP, HVXC, LPC, ADPCM, VQ, speech coding, parametric coding, error protection
Speech coding technology has been developed for the purpose of saving the bandwidth and capacity of communication networks and storage systems when speech signals have to be transmitted or stored. During the last decade, the development of speech coding technology accelerated, especially in the area of quickly evolving personal mobile phone applications [RCR94, TIA99].
An object-based representation of audio signals, such as that provided by the MPEG-4 standards [MPEG4-1, MPEG4-3], requires a high degree of flexibility with respect to the kind of input material, the range of bit rates, and ...