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. 03, 1992
Filed:
Apr. 06, 1990
Claude Galand, Cagnes Sur Mer, FR;
Michele Rosso, Nice, FR;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A process for deriving voice pitch related delay values M to tune a Long-Term Prediction (LTP) filter to be used in an LTP based speech coder converting a speech derived digital signal r(n) into a lower bit rate signal, said filter being provided with a variable length delay line y(n) fed with a reconstructed signal r'(n). The process includes splitting r(n) into segments and each segment into sub-segments; then cross-correlating the first current r(n) sub-segment with a previously reconstructed segment and sorting the cross-correlation values for peak location, whereby a first delay value M1 is derived and used to tune the filter. Then, said M1 is used to compute sample indexes n for a predefined number of samples located about M1/p, . . . , M1, 2M1, . . . , pM1 and repeating cross-correlation and sorting operations to derive M2 and so on up to a full segment length (e.g. 160 samples). Then the process is started all over again.