Speech signal encoding method and speech signal decoding method

摘要

A speech signal encoding method and a speech signal decoding method are provided. The speech signal encoding method includes the steps of specifying an analysis frame in an input signal; generating a modified input based on the analysis frame; applying a window to the modified input; generating a transform coefficient by performing an MDCT (Modified Discrete Cosine Transform) on the modified input to which the window has been applied; and encoding the transform coefficient. The modified input includes the analysis frame and a self replication of all or a part of the analysis frame.

主权项

1. A speech signal encoding method by an apparatus, the method comprising:
specifying, by the encoding apparatus, an analysis frame in an input speech signal; generating, by the encoding apparatus, a first modified input speech, based on the analysis frame by adding replication of all or a part of the analysis frame to the analysis frame; applying, by the encoding apparatus, a window on the first modified input to generate a second modified input and a third modified input, each of which has a same length as the window, wherein the window is of equal length or shorter than the first modified input, and the second half of the first modified input overlaps with the first half of the second modified input, and wherein the window has a symmetrical shape that includes four sub-frames with weights w1, w2, w3 and w4, the weights satisfying the condition w1w1+w3w3=w2w2+w4w4=1; generating, by the encoding apparatus, transform coefficients by performing a Modified Discrete Cosine Transform (MDCT) on the second and third modified inputs; and encoding the transform coefficients by the encoding apparatus.