| 摘要 |
Wide-band speech signals and also music signals are coded with relatively less computational efforts and less sound quality deterioration even at low bit rates. A spectral parameter calculator obtains a spectral parameter from sub-frames of an input signal from a sub-frame divider, and quantizes the obtained spectral parameter. A divider divides the difference result from a subcontractor into a plurality of sub-bands. Adaptive codebook circuits obtain a pitch prediction signal by obtaining pitch data in at least one of the sub-bands. Judging circuits execute pitch prediction judgment by using the pitch data in at least one of the sub-bands. A synthesizer synthesizes a pitch prediction signal. A subtractor subtracts the pitch prediction signal from the difference result obtained from a subtractor and thus obtains an excitation signal. An excitation quantizer quantizes the excitation signal with reference to an excitation codebook.
|
