A low-delay wideband speech coder at 24-kbps
نویسندگان
چکیده
A novel low-delay wideband speech coder, called Multiband CELP (MB-CELP) achieves a delay of about 10 ms, by exploiting time-domain correlations with a twostage linear prediction scheme. A low-order forwardadaptive LP stage models coarse shape, and a highorder backward-adaptive LP stage models ne structure of the input spectrum. A conditional pitch prediction method improves the performance of the coder for speech without degrading music performance. A multi-band bank of o -line ltered codebooks generates the excitation signal. A 24 kbps version of the coder has nine multi-band codebooks with nonuniform bandwidth. Subjective comparison tests show that this coder outperforms the G.722 coder at the bit-rate of 56 kbps.
منابع مشابه
A multi-band CELP wideband speech coder
A novel low-delay wideband speech coder, called Multiband CELP (MB-CELP), overcomes the major obstacles usually associated with two traditional CELP approaches to wideband speech coding namely fullband CELP and split-band CELP. The new MB-CELP coder employs a multi-band bank of o -line ltered excitation codebooks, fullband linear prediction synthesis, and minimization of the error between origi...
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