A new wavelet-based wide-band speech coder
Tác giả
Tóm tắt
There are several methods and standards for speech coding. Most of them are used for narrowband speech. In multimedia communication systems, wideband speech coding plays an important role. Wavelet is an efficient signal processing tool for speech coding. Conventional wavelet speech coders use wavelet global or sub-band dependent threshold to allocate bits in each sub-band. Using psychoacoustic model with temporal and simultaneous properties, we will be able to estimate the threshold close to human hearing. This paper presents a wavelet packet based wideband speech coding incorporating both backward temporal, forward temporal and simultaneous masking models. The coder uses also Huffman lossless compression. By applying this model we were calculated the bit rate results of approximately 25 kbps while preserving perceptual quality with single channel wide-band speech sampled at 16 KHz.