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:
Mar. 29, 2005
Filed:
Jul. 31, 2000
Walter Voessing, Hannover, DE;
Fei Gao, Hannover, DE;
Andreas Aust, Hannover, DE;
Thomson Licensing S.A., Boulogne-Billancourt, FR;
Abstract
MPEG 1 Audio data compression is based on subband coding. A quantization is performed using a psychoacoustic model which is adapted to the masking behavior of the human hearing. Each subband signal is quantized in such a way that the quantization noise introduced by the coding will not exceed the masking curve for that subband. In ISO/IEC 11172-3 two independent psychoacoustic models are defined. The output from these psychoacoustic models is a set of Signal-to-Masking Ratios, SMR, for every subband n. In order to calculate the SMRfor the psychoacoustic model 2 according to the invention a Fast Fourier Transformation is performed with a length of L=1152 samples by calculating k subtransformations over 2samples with k*2=L and fitting together the results of the k subtransformations.