METHOD FOR ENCODING AND DECODING AUDIO SIGNAL

摘要

PROBLEM TO BE SOLVED: To encode a rising part with a satisfactory sound quality by detecting the discontinuous point of audio signals inputted as a discrete sample stream, extracting audio signal sample blocks, which are divided by the discontinuous point, as unit blocks, encoding the time point of dividing the unit blocks, independently encoding respective unit blocks and outputting these codes. SOLUTION: The audio signal is inputted to a rising detecting part 1 and a frame dividing part 2 and outputted by the rising detecting part 1 as the rising flag of value '1' or '2'. A time/frequency converting part 3 converts the sample stream received from the frame dividing part 2 to the coefficient sample stream of a frequency area while using MDCT. An encoding part 4 encodes the MDCT coefficient sample outputted form the time/frequency converting part 3. A bit stream generating part 5 converts the codes received from the frame dividing part 2 and the encoding part 4 to the binary numbers of indexes and these binary numbers are arranged in the predetermined order and outputted as a bit stream.