Data reproduction device, method thereof and storage medium

摘要

A frame, which is the data unit, is extracted without decoding MPEG audio data. Then, a scale factor included in the frame is extracted and an evaluation function is calculated based on the scale factor. If the value of the evaluation function is larger than a prescribed threshold value, the speed of the frame is converted. If the value of the evaluation function is smaller than the prescribed threshold value, the frame is judged to be a frame in a silent section and neglected. The speed conversion is made by thinning out frames or repeating the same frame as many times as required according to prescribed rules.