Patent ID: 7692087

Claim:
A waveform data compression method comprising: a step of segmenting waveform data comprising a plurality of sample values into a plurality of portions; a step of setting a loop start point and loop end point in the waveform data in such a manner that at least one of the loop start point and loop end point is set at an enroute point of the portion to which the start point or end point belongs; a step of generating compression parameters for compressing each of the portions of the waveform data; a step of compressing each of the portions of the waveform data on the basis of the compression parameters, generated by said step of generating, to obtain compression codes of the portion; a step of forming, for each of the portions, a frame including compression codes of the portion corresponding to the frame and decompression parameters to be used for decompression of a next one of the portions, said decompression parameters corresponding to the compression parameters used for compressing a portion corresponding to said next one of the portions by said step of compressing, wherein the portion having the loop start point or loop end point set at the enroute point thereof is compressed so as to have same decompression parameters as another portion preceding or following said portion; and a step of writing the frame, formed by said step of forming, into a memory.