The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 10, 2003
Filed:
Jan. 09, 2002
Atsushi Hotta, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
An audio signal encoding apparatus is provided which is capable of preventing deterioration in the objective characteristics of a signal to be encoded without using parameters from a psychoacoustic model generated based on human auditory characteristics or by replacing such parameters with those by which the signal can be effectively quantized in cases where the width of a frequency band in which frequency component such as a sine wave of the signal concerned exists is narrow. The audio signal encoding apparatus includes a psychoacoustic model section , an MDCT processing section and an iterative loop processing section . The psychoacoustic model section includes an FFT operation section , a block type determination section and an SMR operation section . The iterative loop processing section includes an allowable error amount calculation section , a bit amount/error amount control section , a normalization processing section , a quantization section and a Huffman encoding section . The apparatus further includes a multiplexer section for multiplexing a processing block type from the block type determination section , a scale factor from the bit amount/error amount control section , a Huffman code book number and a Huffman code from the Huffman encoding section , a sine wave discrimination section for discriminating whether or not the input signal is a sine wave, by using the FFT frequency spectrum calculated by the FFT operation section , and a switching element for switching between use and nonuse of an output value of the SMR operation section based on the result of sine wave discrimination in the sine wave discrimination section