Audio signal time scale modification
US6944510B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 2000 |
| Grant date | Sep 13, 2005 |
| Priority date | — |
| Expiry date | May 22, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L25/06
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method of time-scale modification processing of frame-based digital audio signals based on Synchronous Overlap Addition in which an original frame of digital audio is copied, the original and copied frames are partly overlapped to give a desired new duration to within a predetermined tolerance, the extent of overlap is adjusted within the predetermined tolerance by reference to a cross correlation determination of the best match between the overlapping portions of the original and copied frame; and a new audio frame is generated from the non-overlapping portions of the original and copied frame and by cross-fading between the overlapping portions. To reduce the computational load, a profiling procedure is applied to the original and copied frame prior to cross correlation, such as to reduce the specification of each audio frame portion (100) to a finite array of values (101–106), and the cross correlation is then performed in relation only to the pair of finite arrays of values. To further simplify computation, the values (101–106) are identified as maxima or minima for the signal and are both stored and processed as the only non-zero values in a matrix representation of the fram…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.