PURPOSE: To improve the quality of a synthesized voice with interpolation to a bad frame.
CONSTITUTION: This device is provided with a rising detection circuit 111 for detecting a rising part from the information of frames before an behind the bad frame so as to improve the quality at the rising of a voice, lag calculation circuit 110 for obtaining lag information from synthesized exciting signals in the past, pulse generation circuit 109 for generating a pulse exciting signal based on the lag information, and switching means 107 for selecting by replacing the pulse exciting signal for an adaptive exciting signal. Further, an adding ratio calculation circuit 120 is provided for obtaining a gain for each exciting signal from the information of frames before and behind the bad fram in order to improve the quality in a section where the adding ratio of the two kinds of exciting signals is changed. Then, the device is provided with a power interpolator 130 for estimating power information in order to improve the quality in a power change, and power correcting means 131 for correcting power corresponding to the estimated result.
| JPH08137495 | VOICE ENCODING DEVICE |
| JPH11184500 | VOICE ENCODING SYSTEM AND VOICE DECODING SYSTEM |
| JP3144284 | SOUND CODING DEVICE |
HOSODA KENICHIRO
KATSURAGAWA HIROSHI
ARIYAMA YOSHIHIRO
