Analysis-by-synthesis multimode harmonic speech coding at 4 kb/s
نویسندگان
چکیده
This paper presents a 4 kb/s Analysis-by-Synthesis Multimode Harmonic Coder (AbS-MHC). Novel features of this coder include a signal modification technique that allows time-domain analysisby-synthesis parameter estimation in sinusoidal coding framework, and a frequency-domain transition speech model with improved parameter estimation and quantization schemes. An efficient quantization scheme for harmonic magnitudes based on Weighted NonSquare Transform Vector Quantization (WNSTVQ) is also used. Subjective quality tests indicate that the 4 kb/s AbS-MHC coder outperforms the 5.3 kb/s G.723.1 standard CELP coder and produces speech quality very similar to the 6.3 kb/s G.723.1 coder.
منابع مشابه
Analysis-by-synthesis low-rate multimode harmonic speech coding
This paper presents an analysis-by-synthesis multimode harmonic coder (AbS-MHC) that employs new techniques to improve both the speech model accuracy and the parameter estimation robustness in the low rate harmonic coding framework. To improve the speech model accuracy, an enhanced frequency domain transition model is used in conjunction with the sinusoidal model based harmonic coding of voiced...
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