Encoder and decoder

An encoding method for encoding an acoustic time-series signal, comprising:

• a band separating step of separating an input acoustic time-series signal into N bands and generating N band signals;
• a normalization coefficient generating step of generating a predetermined normalization coefficient for each of the band signals;
• a normalization step of normalizing the band signals on the basis of the generated normalization coefficients;
• a quantization accuracy information generating step of generating quantization accuracy information for each of the band signals;
• a quantization step of quantizing each of the normalized band signals on the basis of the quantization accuracy information;
• a plurality of normalization coefficient encoding steps of encoding the N normalization coefficients, which are generated in the normalization coefficient generating step;
• a selection step of selecting one of the normalization coefficient encoding steps on the basis of the amount of encoding in a case in which the N normalization coefficients are encoded in each of the normalization coefficient encoding steps;
• and
• a multiplexing step of multiplexing the N normalization coefficients, which are encoded using the normalization coefficient encoding step selected in the selection step, and each of the band signals, which are output in the quantization step.

A recording medium having a computer-readable program recorded therein, the program comprising:

• a band separating step of separating an input acoustic time-series signal into N bands and generating N band signals;
• a normalization coefficient generating step of generating a predetermined normalization coefficient for each of the band signals;
• a normalization step of normalizing the band signals on the basis of the generated normalization coefficients;
• a quantization accuracy information generating step of generating quantization accuracy information for each of the band signals;
• a quantization step of quantizing each of the normalized band signals on the basis of the quantization accuracy information;
• a plurality of normalization coefficient encoding steps of encoding the N normalization coefficients, which are generated in the normalization coefficient generating step;
• a selection step of selecting one of the normalization coefficient encoding steps on the basis of the amount of encoding in a case in which the N normalization coefficients are encoded in each of the normalization coefficient encoding steps;
• and
• a multiplexing step of multiplexing the N normalization coefficients, which are encoded using the normalization coefficient encoding step selected in the selection step, and each of the band signals, which are output in the quantization step.

An encoding device for encoding an acoustic time-series signal, comprising:

• band separating means for separating an input acoustic time-series signal into N bands and generating N band signals;
• normalization coefficient generating means for generating a predetermined normalization coefficient for each of the band signals;
• normalization means for normalizing the band signals on the basis of the generated normalization coefficients;
• quantization accuracy information generating means for generating quantization accuracy information for each of the band signals;
• quantization means for quantizing each of the normalized band signals on the basis of the quantization accuracy information;
• a plurality of quantization accuracy information encoding means for encoding the N pieces of quantization accuracy information, which are generated by the quantization accuracy information generating means;
• first selection means for selecting one of the quantization accuracy information encoding means on the basis of the amount of encoding in a case in which the N pieces of quantization accuracy information are encoded by each of the quantization accuracy information encoding means;
• and
• multiplexing means for multiplexing the N pieces of quantization accuracy information, which are encoded using the quantization accuracy information encoding means selected by the first selection means, and each of the band signals, which are output by the quantization means.

An encoding method for encoding an acoustic time-series signal, comprising:

• a band separating step of separating an input acoustic time-series signal into N bands and generating N band signals;
• a normalization coefficient generating step of generating a predetermined normalization coefficient for each of the band signals;
• a normalization step of normalizing the band signals on the basis of the generated normalization coefficients;
• a quantization accuracy information generating step of generating quantization accuracy information for each of the band signals;
• a quantization step of quantizing each of the normalized band signals on the basis of the quantization accuracy information;
• a plurality of quantization accuracy information encoding steps of encoding the N pieces of quantization accuracy information, which are generated in the quantization accuracy information generating step;
• a selection step of selecting one of the quantization accuracy information encoding steps on the basis of the amount of encoding in a case in which the N pieces of quantization accuracy information are encoded in each of the quantization accuracy information encoding steps;
• and
• a multiplexing step of multiplexing the N pieces of quantization accuracy information, which are encoded using the quantization accuracy information encoding step selected in the selection step, and each of the band signals, which are output in the quantization step.

A recording medium having a computer-readable program recorded therein, the program comprising:

• a band separating step of separating an input acoustic time-series signal into N bands and generating N band signals;
• a normalization coefficient generating step of generating a predetermined normalization coefficient for each of the band signals;
• a normalization step of normalizing the band signals on the basis of the generated normalization coefficients;
• a quantization accuracy information generating step of generating quantization accuracy information for each of the band signals;
• a quantization step of quantizing each of the normalized band signals on the basis of the quantization accuracy information;
• a plurality of quantization accuracy information encoding steps of encoding the N pieces of quantization accuracy information, which are generated in the quantization accuracy information generating step;
• a selection step of selecting one of the quantization accuracy information encoding steps on the basis of the amount of encoding in a case in which the N pieces of quantization accuracy information are encoded in each of the quantization accuracy information encoding steps;
• and
• a multiplexing step of multiplexing the N pieces of quantization accuracy information, which are encoded using the quantization accuracy information encoding step selected in the selection step, and each of the band signals, which are output in the quantization step.

A decoding device for decoding an encoded acoustic signal, comprising:

• demultiplexing means for demultiplexing the multiplexing of at least one band signal with quantization accuracy information and with an encoded normalization coefficient for each band signal;
• normalization coefficient decoding means for decoding the demultiplexed normalization coefficient;
• signal generating means for dequantizing each band signal on the basis of the quantization accuracy information and for denormalizing the dequantized signal on the basis of the normalization coefficient, whereby an acoustic time-series signal is generated;
• and
• combining means for combining bands of band signals generated by the signal generating means.

A decoding method for decoding an encoded acoustic signal, comprising:

• a demultiplexing step of demultiplexing the multiplexing of at least one band signal with quantization accuracy information and with an encoded normalization coefficient for each band signal;
• a normalization coefficient decoding step of decoding the demultiplexed normalization coefficient;
• a signal generating step of dequantizing each band signal on the basis of the quantization accuracy information and for denormalizing the dequantized signal on the basis of the normalization coefficient, whereby an acoustic time-series signal is generated;
• and
• a combining step of combining bands of band signals generated in the signal generating step.

A recording medium having a computer-readable program recorded therein, the program comprising:

• a demultiplexing step of demultiplexing the multiplexing of at least one band signal with quantization accuracy information and with an encoded normalization coefficient for each band signal;
• a normalization coefficient decoding step of decoding the demultiplexed normalization coefficient;
• a signal generating step of dequantizing each band signal on the basis of the quantization accuracy information and for denormalizing the dequantized signal on the basis of the normalization coefficient, whereby an acoustic time-series signal is generated;
• and
• a combining step of combining bands of band signals generated in the signal generating step.

A decoding device for decoding an encoded acoustic signal, comprising:

• demultiplexing means for demultiplexing the multiplexing of at least one band signal with a normalization coefficient and with encoded quantization accuracy information for each band signal;
• quantization accuracy information decoding means for decoding the demultiplexed quantization accuracy information;
• signal generating means for dequantizing each band signal on the basis of the quantization accuracy information and for denormalizing the dequantized signal on the basis of the normalization coefficient, whereby an acoustic time-series signal is generated;
• and
• combining means for combining bands of band signals generated by the signal generating means.

A decoding method for decoding an encoded acoustic signal, comprising:

• a demultiplexing step of demultiplexing the multiplexing of at least one band signal with a normalization coefficient and with encoded quantization accuracy information for each band signal;
• a quantization accuracy information decoding step of decoding the demultiplexed quantization accuracy information;
• a signal generating step of dequantizing each band signal on the basis of the quantization accuracy information and for denormalizing the dequantized signal on the basis of the normalization coefficient, whereby an acoustic time-series signal is generated;
• and
• a combining step of combining bands of band signals generated in the signal generating step.

A recording medium having a computer-readable program recorded therein, the program comprising:

• a demultiplexing step of demultiplexing the multiplexing of at least one band signal with a normalization coefficient and with encoded quantization accuracy information for each band signal;
• a quantization accuracy information decoding step of decoding the demultiplexed quantization accuracy information;
• a signal generating step of dequantizing each band signal on the basis of the quantization accuracy information and for denormalizing the dequantized signal on the basis of the normalization coefficient, whereby an acoustic time-series signal is generated;
• and
• a combining step of combining bands of band signals generated in the signal generating step.