MDCP: Patent Abstact US05960390: Coding method for using multi channel audio signals

US05960390 Coding method for using multi channel audio signals

Assignee Sony Corporation

Assign./Filed Sept. 28, 1999/ Oct. 2, 1996

Inventors Ueno; Masatoshi, Miyamori; Shinji

Summary ATRAC2/3 Gain Control.

Abstract There is provided a coding method which can effectively prevent a pre-echo and a post-echo from being generated and can perform effective coding to which an psycho-acoustic model is applied. A coding apparatus according to the coding method of the present invention detects the attack and release portions of a waveform signal, and performs gain control to a waveform signal before the attack portion and the waveform signal of the release portion by using a gain control amount adaptively calculated according to the characteristics of the waveform signal. An psycho acoustic model window circuit to an aural model application circuit calculate a masking level based on the psycho-acoustic model from a frequency component obtained by transforming the waveform signal, and a quantization precision determination circuit determines a quantization precision by using the masking level. An window circuit and a transform circuit transform the waveform signal into a plurality of frequency components. The quantization circuit quantizes the plurality of frequency components by using the quantization precision.

US05960390	Coding method for using multi channel audio signals
Assignee	Sony Corporation
Assign./Filed	Sept. 28, 1999/ Oct. 2, 1996
Inventors	Ueno; Masatoshi, Miyamori; Shinji
Summary	ATRAC2/3 Gain Control.
Abstract	There is provided a coding method which can effectively prevent a pre-echo and a post-echo from being generated and can perform effective coding to which an psycho-acoustic model is applied. A coding apparatus according to the coding method of the present invention detects the attack and release portions of a waveform signal, and performs gain control to a waveform signal before the attack portion and the waveform signal of the release portion by using a gain control amount adaptively calculated according to the characteristics of the waveform signal. An psycho acoustic model window circuit to an aural model application circuit calculate a masking level based on the psycho-acoustic model from a frequency component obtained by transforming the waveform signal, and a quantization precision determination circuit determines a quantization precision by using the masking level. An window circuit and a transform circuit transform the waveform signal into a plurality of frequency components. The quantization circuit quantizes the plurality of frequency components by using the quantization precision.