| 摘要 |
PROBLEM TO BE SOLVED: To reduce a calculation amount of a sound signal decoding device accompanied by signal conversion processing from a frequency domain to a time domain while creating a suitable output sound signal.SOLUTION: An output control section 340 receives window information including a window shape for indicating a classification of a window function regarding the window processing of an input channel from a code string separation section 310, and switches the connection of an output sections 351 to 355 to a frequency domain mixing section 510 if the window information is wholly the same. The frequency domain mixing section 510 mixes frequency domain signals of five channels from a decoding and inverse quantization section 320 based on down-mix information for making the number of output channels smaller than the number of input channels. An Inverse Modified Discrete Cosine Transform(IMDCT) and window processing sections 521 and 522 converts a 2-channel frequency domain signal which is outputted from the frequency domain mixing section 510 to the time domain signal, and outputs it as a 2-channel sound signal. |
