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Author Jasiuk, Mark ♦ Ramabadran, Tenkasi
Source CiteSeerX
Content type Text
File Format PDF
Subject Domain (in DDC) Computer science, information & general works ♦ Data processing & computer science
Subject Keyword Adaptive Equalizer Analysis-by-synthesis Speech Coder ♦ Speech Encoder ♦ Short-term Predictor Parameter ♦ Transmitted Parameter ♦ Recon-structed Speech ♦ Frequency Domain ♦ Analysis-by-synthesis Speech Coder ♦ Objective Evaluation ♦ En-hanced Variable Rate Coder ♦ Standard Coder ♦ Celp Coder ♦ Itu Rec-ommended Voice Quality Tool ♦ Desired Characteristic ♦ Reconstructed Speech ♦ Experimental Result ♦ Computed Set ♦ Matching Set
Abstract An equalizer to enhance the quality of reconstructed speech from an analysis-by-synthesis speech coder, e.g., CELP coder, is described. The equalizer makes use of the set of short-term predictor parameters normally transmitted from the speech encoder to the decoder. In addition, the equalizer computes a matching set of parameters from the recon-structed speech. The function of the equalizer is to undo the computed set of characteristics from the reconstructed speech and impose the set of desired characteristics repre-sented by the transmitted parameters. Design steps for the equalizer and its implementation both in time and frequency domain are described. Experimental results of applying the equalizer to the output of a standard coder, viz., EVRC (En-hanced Variable Rate Coder) operating at half-rate (4000 bps), are presented. Objective evaluation using an ITU rec-ommended voice quality tool shows that the equalizer can help enhance the quality of the reconstructed speech signifi-cantly. 1.
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Research
Education Level UG and PG ♦ Career/Technical Study