METHOD AND SYSTEM FOR ENCODING AND DECODING SPEECH SIGNAL PROCESSED BY USING MANY SUBBANDS AND WINDOW FUNCTIONS OVERLAPPING EACH OTHER

PROBLEM TO BE SOLVED: To improve the adaptation of the lengths or window shapes of the blocks or windows permitted within the entire range of subbands in encoding and decoding of speech signals using the subbands and window functions overlapping each other. SOLUTION: In an MPEG (Moving Picture Expert Group)-1 Audio Layer 3, a decoder already knows about the succeeding blocks and windows by the occurrence of a parameter window switching flag after the window switching flag and therefore the transmission of the changing block parameter types several times is redundant. Two corresponding bits are used to inform the decoder of the different kinds of the different subband signal window changeover setting. The setting kinds determine which subbands among all of the subbands to be used are affected by the above parameter window switching flag or which subbands are not affected by the same. The setting kinds further determine the fixed or variable different subband groups to be affected by the parameter window switching flag among all the subbands. COPYRIGHT: (C)2004,JPO