Method for performing time-scale modification of speech information or speech signals
US4864620A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 3, 1988 |
| Grant date | Sep 5, 1989 |
| Priority date | — |
| Expiry date | Feb 3, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L21/04
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Pre-recorded speech is played back at a different rate, without pitch change. Adjacent signal segments are combined with best match processing. Method and apparatus process time domain speech signals containing speech information, the rate of reproduction of which is to be varied without changing pitch, wherein the input signal is processed by capturing input time domain speech samples in frames wherein the number of samples per frame is a function of a desired speech change factor, forming blocks from the frames, additively cross correlating input blocks with prior-processed or output blocks, preferably by means of an Average Magnitude Difference Function, to obtain a time relation of best match for the rate of reproduction, adding consecutive input and output blocks at the point of maximum correlation, and applying a window function between the overlapping portions of the output block and the input block to obtain a new output block. The method does not require multiplication or division. Relatively smooth transitions between superimposed segments of speech which become output blocks are realized by applying a graduated weighting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.