| 摘要 |
The invention relates to a method for improving the coding accuracy and transmission efficiency of an audio signal. According to the method, a part of the audio signal to be coded is compared with earlier stored samples of the audio signal and a reference sequence of samples that best corresponds to the audio signal to be coded is identified. Predicted signals are produced from the reference sequence by means of long-term prediction, using at least two different LTP orders (M), a group of pitch predictor coefficients (b(k)) being formed for each pitch predictor order. The predicted signals for each pitch predictor order are compared with the audio signal to be coded in order to determine a prediction error. The amount of information required to code the predicted signals is compared with the amount of information required to code the original signal and a coding method that provides the best representation of the audio signal while minimising the amount of data required is selected. <IMAGE> |
