Performance Analysis of A Variable Bit Rate Speech Coder

A 2.4 kbps variable bit rate ADP-CELP speech coder

This paper presents a variable bit rate ADP-CELP (Adaptive Density Pulse Code Excited Linear Prediction) coder that selects one of four kinds of coding structure in each frame based on short time speech characteristics. To improve speech quality and reduce the average bit rate, we have developed a speech/non-speech classification method using spectrum envelope variation, which is robust for bac...

A low bit rate speech coder based on Gaussian adaptivewaveletsShubha

A low bit rate speech coder based on Gaussian adaptive wavelets is described. This speech coder ameliorates the problem of using two diierent mother wavelets to model voiced and unvoiced sounds as mentioned in. 1 In addition, it has been demonstrated in this paper, that Gaussian adaptive wavelets are better suited to model both voiced and unvoiced sounds as compared to Morlet and Daubechies' wa...

A Full-Fuzzy Rate Controller for Variable Bit Rate Video

In this paper, we propose a new full-fuzzy video ratecontrol algorithm (RCA) for variable bit rate (VBR) videoapplications. The proposed RCA provides high qualitycompressed video with a low degree computational complexity.By controlling the quantization parameter (QP) on a picturebasis, it produces VBR video bit streams. The proposed RCAhas been implemented on the JM H.264/AVC video codec andth...

Source controlled variable bit-rate speech coder based on waveform interpolation

This paper describes a source controlled variable bit-rate (SCVBR) speech coder based on the concept of prototype waveform interpolation. The coder uses a four mode classification : silence, voiced, unvoiced and transition. These modes are detected after the speech has been decomposed into slowly evolving (SEW) and rapidly evolving (REW) waveforms. A voicing activity detection (VAD), the relati...

Hybrid transform coder for low bit rate speech coding