| 摘要 |
PROBLEM TO BE SOLVED: To reproduce an excellent speech without deterioration in speech quality at a switching place at reproduction time by providing a control means which continues the encoding by the same speech encoding means until the decision result of a speech decision means indicates that a sound is voiceless and switches the encoding to another speech encoding means once the voiceless sound is decided. SOLUTION: The input signal from a microphone 1 is converted by an A/D converter 4 into a digital signal and a speech decision unit 16 decides whether the sound is voiced or voiceless. Then when a user switches an operation input part 18 during sound recording to select a high-quality sound recording mode or long-time sound recording mode, a system control part 17 places a coder decoder 14 or coder decoder 15 selectively in operation according to the switching operation for the sound-recording mode. The encoding by the same encoder decoder is carried on until the decision result of the speech decision unit 16 indicates the voiceless sound, and once the voiceless sound is decided, the switching to another encoding means is performed. |
