Encoding device, decoding device, encoding method, and decoding method
AssigneePanasonic Intellectual Property Corporation of America
InventorsSrikanth NAGISETTY, Hiroyuki EHARA, Akira HARADA, Chong Soon LIM
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Abstract
The present invention reduces the number of encoded bits in vector quantization. This encoding device is provided with: a quantizing circuit which generates quantization parameters including first information on a vector quantization codebook, and second information on code vectors included in the codebook; and a control circuit which employs the second number of bits based on the difference between the first number of bits available for encoding of a sub-vector in the vector quantization, and the number of bits for the sub-vector quantization parameters, to control encoding of the first information with respect to the sub-vector.
Claims18
An encoder of an audio or speech signal, the encoder comprising:
- quantization circuitry, which, in operation, divides a signal into a plurality of sub-vectors and, in operation, generates quantization parameters including a codebook index and a code vector index for each of the plurality of sub-vectors, the codebook index indicating a codebook for vector quantization, the code vector index indicating one of a plurality of code vectors included in the codebook;
- and
- control circuitry, which, in operation, controls:
- calculating a number of usable bits for encoding the quantization parameters for a certain sub-vector among the plurality of sub-vectors by subtracting a total number of bits for encoding the quantization parameters for the plurality of sub-vectors except the quantization parameters for the certain sub-vector from a number of available bits for encoding the quantization parameters for the signal in the frequency domain;
- calculating a remainder of five of the number of usable bits and subtracting the calculated value of the remainder from the number of usable bits for the certain sub-vector to obtain a subtraction result;
- and
- calculating a number of unused bits for the certain sub-vector by subtracting a number of bits necessary for encoding the quantization parameters for the certain sub-vector from the subtraction result;
- encoding the number of unused bits and the code vector index for the certain sub-vector;
- and
- encoding the quantization parameters for the plurality of sub-vectors except the certain sub-vector.
An encoding method for an encoder of an audio or speech signal, the encoding method comprising:
- dividing the signal in the frequency domain into a plurality of sub-vectors;
- generating quantization parameters including a codebook index and a code vector index for each of the plurality of sub-vectors, the codebook index indicating a codebook for vector quantization, the code vector index indicating one of a plurality of code vectors included in the codebook;
- and
- controlling:
- calculating a number of usable bits for encoding the quantization parameters for a certain sub-vector among the plurality of sub-vectors by subtracting a total number of bits for encoding the quantization parameters for the plurality of sub-vectors except the quantization parameters for the certain sub-vector from a number of available bits for encoding the quantization parameters for the signal in the frequency domain;
- calculating a remainder of five of the number of usable bits and subtracting the calculated value of the remainder from the number of usable bits for the certain sub-vector to obtain a subtraction result;
- and
- calculating a number of unused bits for the certain sub-vector by subtracting a number of bits necessary for encoding the quantization parameters for the certain sub-vector from the subtraction result;
- encoding the number of unused bits and the code vector index for the certain sub-vector;
- and
- encoding the quantization parameters for the plurality of sub-vectors except the certain sub-vector.
Dependencies are inferred from the claim text.