Sony Corporation

Mito Sonohara

Kyoya Tsutsui

Osamu Shimoyoshi

Robert Heddle

A signal encoding method and apparatus for encoding an acoustic signal, a recording medium having the encoded signals, a method for transmitting the encoded signals, and a signal decoding apparatus for decoding the encoded signals, are disclosed. With the encoding apparatus, an attack portion detection circuit detects an attack portion of the waveform acoustic signal where the waveform elements of the waveform acoustic signal rise sharply. A gain control circuit controls the gain for waveform elements at least upstream of the attack portion using a gain control amount adaptively selected from plural gain control amounts specified by a pre-set power of 2. A forward orthogonal transform circuit transforms the waveform acoustic signal into plural spectral components. A normalization and encoding circuit normalizes, quantizes and encodes the gain control information an plural spectral components. With the encoding apparatus, the encoding efficiency may be improved without complicating the construction, while the pre-echo may be suppressed effectively.

Gain control method and gain control apparatus for digital audio signals

An encoding apparatus for encoding a digital signal and a decoding apparatus for decoding the encoded signal. This encoding apparatus comprises a time series sample buffer for dividing an input signal into blocks, an orthogonal transform encoding section for transforming the signals every blocks into spectrum signals, and an entropy encoding section for implementing variable length encoding to all or a portion of the spectrum signals every blocks. At the entropy encoding section, there are provided an upper limit setting circuit for setting upper limit in the number of bits per each block of a signal encoded and outputted, and a bit number judging circuit for stopping outputting of a portion of spectrum signals in a block or blocks where the number of bits above the upper limit is required. The number of bits per each block is caused to have upper limit to stop recording or transmission of a portion of spectrum signals in a block or blocks where the number of bits above the upper limit is required. Thus, quantity of information caused to undergo encoding, recording or transmission and decoding can be reduced.

Method and apparatus for encoding digital signal method and apparatus

Signal encoding method and apparatus using selected predetermined code

Signal encoding method, signal encoding apparatus, signal decoding

Method and apparatus for variable length encoding of separated tone and

Information encoding method and apparatus, and information decoding

Method and apparatus for encoding digital signal, method and apparatus

Information encoding method and apparatus, information decoding method

An MDCT calculating circuit includes an x.sub.01 calculating circuit for multiplying input signals with a forward transforming window and a linear forward transforming unit for linear forward transforming an output signal of the calculating circuit. The linear forward transforming unit includes an x.sub.02 calculating circuit and an x.sub.03 calculating circuit for pre-processing the output signal of the x.sub.01 calculating circuit and an integration and summation processing circuit for executing integration and summation processing operations on an output signal of the pre-processing unit. The integration and summation processing circuit executes an integration and summation operation on an N/2 number of input signals from the pre-processing unit by grouping a k number of input signals as a processing unit and iteratively executes the integration and summation processing operations a N/(2*K) number of times for outputting a sum total of N/2 number of signals.

Inverse modified discrete cosine transform signal transforming system

Modified discrete cosine transform signal transforming system

A data encoding method apparatus in which the volume of arithmetic-logical operations for calculating the total number of bits required for encoding for adaptive bit allocation in the variable length encoding system for expediting the processing. In the data encoding apparatus for encoding and subsequently variable length encoding the input data, spectral data obtained on orthogonal transform coding are routed to a block floating circuit 403 for normalization and re-quantized in a quantization circuit 404 depending on the bit allocation number information from a bit allocation calculating circuit 406 so as to be then variable length encoded by an encoding circuit 407 and outputted at an output terminal 408. The bit allocation circuit 406 refers to a table memory circuit 409 in which re-quantized data domain is divided at boundary points corresponding to code length transitions in order to calculate the total number of bits required for encoding using a smaller volume of arithmetic-logical operations for the purpose of adjusting the number of allocated bits.

Method and apparatus for data encoding and data recording medium

Growing community of inventors

Kanagawa, Japan

Mito Sonohara