- Volume 15 Issue 4
A low bit rate speech coder based on the non-uniform sampling technique is proposed. The non-uniform sampling technique is based on the detection of inflection points (IP). A speech block is processed by the IP detector, and the detected IP pattern is compared with entries of the IP database. The address of the closest member of the database is transmitted with the energy of the speech block. In the receiver, the decoder reconstructs the speech block using the received address and the energy information of the block. As results, the coder shows fixed data rate contrary to the existing speech coders based on the non-uniform sampling. Through computer simulation, the usefulness of the proposed technique is shown. The SNR performance of the proposed method is approximately 5.27 dB with the data rate of 1.5 kbps.
Non-uniform sampling;Inflection point detection;Low rate speech coder
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- 1. A Fixed Rate Speech Coder Based on the Filter Bank Method and the Inflection Point Detection vol.16, pp.4, 2016, doi:10.5391/IJFIS.2015.15.4.300
연구 과제 주관 기관 : Gangneung-Wonju National University