High efficiency encoding method

A high efficiency encoding method comprising the steps of:

• determining an M-dimensional vector on the basis of data obtained by dividing an input audio signal on a block-by-block basis thus generating blocks each comprising a variable number of parameter data, performing time domain to frequency domain conversion on one of the blocks of the signal to generate frequency domain data, and generating from the frequency domain data a fixed number of data determining the M-dimensional vector;
• and
• processing the M-dimensional vector in accordance with vector quantization.

A high efficiency encoding method comprising the steps of:

• determining an M-dimensional vector for each block of an input audio signal by dividing the input audio signal on a block-by-block basis, performing time domain to frequency domain conversion on each block of the signal to generate frequency domain data, and performing an inter-block difference operation on the frequency domain data;
• and
• processing each said M-dimensional vector in accordance with vector quantization.

A high efficiency encoding method comprising the steps of:

• determining M-dimensional vectors by dividing an input audio signal on a block-by-block basis and performing time domain to frequency domain conversion on each block of the audio signal to generate frequency domain data for said each block, wherein the audio signal is a voice signal;
• and
• performing quantization, by using a vector quantizer having plural codebooks according to a state of the input audio signal to process each said M-dimensional vector in accordance with vector quantization, and by changing over the plural codebooks in accordance with a parameter indicating characteristics of said each block of the voice signal, wherein a first one of the codebooks is employed to process at least one of the M-dimensional vectors for which the parameter indicates that a corresponding portion of the voice signal is voiced, and a second one of the codebooks is employed to process at least one of the M-dimensional vectors for which the parameter indicates that a corresponding portion of the voice signal is unvoiced.