Abstract: Data representing an information signal are non-linearly quantized to generate respective quantized data that represent the information signal using fewer bits. Each of the data, when non-linearly quantized, is represented by a quantizing level selected from a number of quantizing levels. The data are non-linearly quantized according to a non-linear function, the decision levels being off-center between adjacent quantizing levels obtained thereby from the quantizing values. The data and word-length information indicating the number of quantizing levels are received. A quantizing value for each quantizing level in the number of quantizing levels is determined from the word-length information and the non-linear function. The quantizing values determined for all the quantizing levels in the number of quantizing levels are non-uniformly spaced. Finally, the quantizing level having the quantizing value closest in value to the data value of each of the data is selected as a respective one of the quantized data.

Abstract: In this invention, an approach is employed to carry out blocking of an input signal to transform the blocked signals into spectrum signals to divide the spectrum signals into a plurality of units to normalize them thereafter to implement variable length encoding to all or a portion of the spectrum signals to output the variable-length encoded signals along with normalization coefficient and the number of re-quantization bits of each unit, wherein an upper limit is provided with respect to the number of bits per each block of a signal to be encoded and outputted to compulsorily change, in a block for which the number of bits above the upper limit is required, normalization coefficient of at least one unit thereafter to re-quantize and entropy-encode a corresponding signal to output the encoded spectrum signal, thereby permitting hardware scale to be smaller as compared to the conventional apparatus without depending upon unevenness of the number of bits by variable length encoding.

Abstract: An information encoding method and apparatus, an information decoding method and apparatus and an information transmission method in which encoding and decoding with higher efficiency and higher sound quality may be achieved by gain control in meeting with the degree of amplitude changes in the attack portion and the pre-echo may be prevented from occurring. Gain control and gain control compensation operations are performed by applying a gain control function with a smaller gain control quantity and by applying a gain control function with a larger gain control quantity to a signal waveform portion having a level just ahead of an attack portion higher than a pre-set level and to a signal waveform portion having an extremely low level just ahead of the attack portion, respectively.

Abstract: The present invention includes an encoding and decoding apparatus and method where there is used a transform processing to allow a waveform element of a corresponding block to interfere with waveform elements of blocks adjoining in both directions at the time of inverse transform processing as in the case of, e.g., MDCT, to compose a waveform signal, amplifying processing in encoding and corresponding correction processing in decoding can be carried out without inconsistency between blocks. Thus, occurrence of pre-echo can be prevented by simple configuration by using spectrum transform processing of high encoding efficiency.

Abstract: A method, and the apparatus for its implementation, for encoding an input signal includes the steps of transforming an input signal into frequency components, as for example by spectrum transform processing, separating the frequency components into a first signal consisting of tone characteristic components and a second signal consisting of other components, encoding the first signal, and encoding a signal based on the second signal.