COMPRESSION METHOD AND DEVICE, DECOMPRESSION METHOD AND DEVICE, COMPRESSION/DECOMPRESSION SYSTEM, AND RECORDED MEDIUM

摘要

A compression device comprises an offset adding section (3) for converting signed digital data of a compression object to unsigned digital data by adding an offset value to the singed digital data, a rounding section (5) for reducing the number of bits per word by rounding the less significant bits of the unsigned digital data, and a timing synthesizer (6) and a compressing section (7) both for sampling the rounded digital data at time intervals between points where the polarities of the differential coefficients change and acquiring a combination of a set of discrete amplitude data values at the sampling points and a set of timing data values representing the time intervals between the sampling points. Consequently the signal on the time axis can be compressed/decompressed without frequency conversion as it is on the time axis.