Performance of adaptive prediction algorithms for trellis coded quantization of speech

Investigates the performance of different adaptive prediction algorithms for use in a low delay, high-quality speech coder at 18 kbit/s. The system to be studied is based on trellis coded quantization (TCQ). In the work presented, the authors demonstrate that when trellises based on feedback-free convolutional encoding circuits are employed, error propagation in TCQ systems is not a serious problem. Performance comparisons are made using a fixed predictor and four different adaptive predictors. Informal listening tests reveal that the encoded speech is of good communications quality at an error rate of 10 ^-3. In an ideal channel, a system employing an all-pole least squares lattice predictor with pitch prediction produces reconstructed speech that is nearly indistinguishable from the original