A wideband speech coder based on harmonic coding at 16KBS
نویسندگان
چکیده
In this paper, we present an improved harmonic coder for the wideband. In an effort to improve spectrum modelling with harmonic representation, we include in the structure, a post error spectrum modelling that is essentially useful for noisy signals or mixed spectra of high pitch voices. The bit constrained error spectrum modelling procedure coupled with an efficient quantization of the harmonic model parameters allow us to develop a low fixed bit rate coder. The detailed structure of all the analysis, synthesis and quantization steps are outlined for the developed 16kbs coder on the [50-7000 Hz] bandwidth. Informal listening tests show that the quality obtained is comparable to the ITU_T Recommendation G722 at 48 kbs.
منابع مشابه
A wideband CELP speech coder at 16 kbit/s based on mel-generalized cepstral analysis
This paper proposes a wideband CELP coder using frequency warping. Instead of linear prediction, the proposed coder adopts the melgeneralized cepstral analysis, and encodes fullband of the speech signal through a warped frequency scale. It is shown that the subjective quality of the proposed coder at 16 kbit/s is better than that of the ITU-T G.722 at 64 kbit/s. Furthermore, the proposed coder ...
متن کاملLossless Wideband Speech Coding
This paper investigates lossless coding of wideband speech by adding a lossless enhancement layer to the lossy baselayer produced by a standardised wideband speech coder. Both the ITU-T G.722 and G.722.2 speech coders are examined. Entropy results show that potential compression rates are dependent on the type and bit rate of the baselayer coder as well as the symbol size used by the lossless c...
متن کاملA 16 kb/s Wideband CELP-Based Speech Coder Using Mel-Generalized Cepstral Analysis
We propose a wideband CELP-type speech coder at 16 kb/s based on a mel-generalized cepstral (MGC) analysis technique. MGC analysis makes it possible to obtain a more accurate representation of spectral zeros compared to linear predictive (LP) analysis and take a perceptual frequency scale into account. A major advantage of the proposed coder is that the benefits of MGC representation of speech ...
متن کاملWideband Speech Coding at 4 kbps using Waveform Interpolation
In this paper we present a new low rate, wideband speech coder operating at 4 kbps and based on Waveform Interpolation (WI). An outline of WI speech coding is provided together with a description of its adaptation to wideband speech. Particular emphasis is placed on the quantisation of the WI parameters. Included is a detailed analysis of the quantisation requirements for the Line Spectral Freq...
متن کاملCoding Wideband Speech at Narrow- Band Bit Rates
The 'rnuffl~d' quality of coded .peech, which arises from the handlimiling ofspeech to 4 kHz, can be reduced either by coding speed! with a wider bandwidth or by widcband enhancement of the narrowband coded speech. ThL~ paper investigates the limitations of wideband enbancement and pO)Ssibilities for its improvement A new wideband coding scheme is prop()sed thaI i. based 00 any narrowband coder...
متن کامل