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:
May. 10, 1994
Filed:
Mar. 23, 1992
Yannick Mahieux, Begard, FR;
France Telecom, , FR;
Abstract
A method and a system process the pre-echoes of an audio-digital signal coded by frequency transformation. The method and the system, after transforming the signal by a frequency transform into transform coefficients y(k), over weighting windows formed over blocks of samples x(n) including N successive samples, and then quantizing the transform coefficients y(k), make it possible to perform, after decoding the transform coefficients y(k), an optimal filtering of KALMAN filtering type. When a transition in amplitude of the signal is present in the sample block, this KALMAN filter reduces the resulting additive noise arising from the quantization coding of the transform coefficients. The method and system may be used in the processing, storage and transmission of high-fidelity quality audio digital signals.