| 摘要 |
PROBLEM TO BE SOLVED: To expand compressed voice data even when an internal memory (work area) is small by performing a synthesizing filter bank process for data after inverse quantization by using stored 2nd data. SOLUTION: An arithmetic unit 11 takes frame information and block information out of an external memory 2, and stores them in an area of the internal memory 12 and 1st data in another area. Then the arithmetic unit 11 takes the compressed voice data out, channel by channel, repeats a process for putting them back in the external memory after inverse quantization, and inversely quantizes the compressed voice data in all blocks constituting one frame. Then the arithmetic unit 11 takes the 2nd data out of the external memory 2, and overwrites them in the area where 1st data are already stored. Then the stored data after the inverse quantization are taken out, channel by channel, a process for putting them back in the external memory is repeated after a synthesizing filter bank process, and a synthesizing filter bank process is performed as to all the blocks constituting the one frame. |
