Voice messaging system with unified pitch and voice tracking
US4696038A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 13, 1983 |
| Grant date | Sep 22, 1987 |
| Priority date | — |
| Expiry date | Apr 13, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L25/93
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
This voice messaging system provides an LPC analyzer in combination with a pitch extractor wherein LPC parameters and a residual signal organized in a sequence of speech data frames are provided by the LPC analyzer as an output representative of an analog speech signal. The pitch extractor is operably associated with the LPC analyzer and produces a plurality of pitch candidates for each of the speech data frames in the sequence thereof. Dynamic programming is performed on the plurality of pitch candidates for each speech data frame and also with respect to a voiced/unvoiced decision of the speech data for each frame by tracking both pitch and voicing from frame to frame to provide an optimal pitch value and also an optimal voicing decision. During dynamic programming, a cumulative penalty for a sequence of frame pitch/voicing decisions is accumulated by defining a transition error between each pitch candidate of a current speech data frame and each pitch candidate of the preceding frame, and defining a cumulative error for each pitch candidate of the current frame equal to the transition error between the pitch candidate of the current frame plus the cumulative error of an optimall…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.