We propose a simple speech compression algorithm using subband division and ADPCM (Adaptive Differential Pulse Code Modulation) algorithm. Although speech data are stored in a semiconductor memory device, its capacity and the available network capacity are limited. Therefore, it is necessary to compress the data as much as possible. The first is that the reconstructed datum must be understood correctly. Speech signal is compressed with a ratio of 1/4 using the proposed subband division and ADPCM (Adaptive Differential Pulse Code Modulation) algorithm.

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Speech Compression