Digital sound recording and reproduction device using a coding technique to compress data for reduction of memory requirements

A sound reproduction device comprising:

• a code excited linear predictive decoder for decoding a coded data which is a sound data coded frame-by-frame by code excited linear predictive coding, each frame comprising a plurality of sub-frames, by using an adaptive code book created on the basis of past excitation signals and a stochastic code book having a plurality of different stochastic signals;
• and
• a controller for skipping the coded data in a predetermined sub-frame of each frame in accordance with a rate of change of reproduction speed to decode the coded data in the remaining sub-frame or sub-frames by said code excited linear predictive decoder without decoding the coded data in the skipped sub-frame, and for renewing the contents of the adaptive code book, when the reproduction speed is increased.

A sound reproduction device comprising:

• a code excited linear predictive decoder for decoding a coded sound data, which is coded frame-by-frame by code excited linear predictive coding with each frame comprising a plurality of sub-frames, by using an adaptive code book created on past excitation signals and a stochastic code book having a plurality of different stochastic signals;
• and
• a controller for repeatedly reading the coded data in a predetermined sub-frame of each frame in accordance with the rate of change of reproduction speed to decode the coded data by said code excited linear predictive decoder, and for renewing the contents of said adaptive code book with a gain of 1 of said adaptive code book and a gain of 0 of said stochastic code book.