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:
Oct. 26, 2004
Filed:
May. 11, 2000
Abstract
In the CELP coding system a low-order synthesis filter and a cascade-connected synthesis filter formed by a cascade connection of low- and high-order synthesis filters are provided, a synthesized acoustic signal is estimated in a mode decision part for an input acoustic signal, and the estimated synthesized acoustic signal is subjected to inverse filtering by an inverse filter corresponding to the low-order synthesis filter and an inverse filter corresponding to the cascade-connected synthesis filter to obtain residual signals. That one of the synthesis filters which corresponds to the residual signal of smaller power is selected by a switch, and a codebook is searched for indices which will minimize the error between the output synthesized acoustic signal by the selected synthesis filter and the input acoustic signal.