Speech decoding and encoding apparatus for lost frame concealment using predetermined number of waveform samples peripheral to the lost frame
US8812306B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 2007 |
| Grant date | Aug 19, 2014 |
| Priority date | — |
| Expiry date | Mar 28, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L47/43
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An audio decoding device capable of suppressing an information amount for a lost flame compensation process and encoding efficiency is provided. A decoded sound source generator generates a lost frame's CELP decoded sound source signal. A pitch pulse information decoder CELP decodes a pitch pulse position information and a pitch pulse amplitude information. A pitch pulse waveform learner learns a pitch pulse learning waveform in a past frame in advance from the lost frame. A convolution adjuster amplitude-adjusts the pitch pulse learning waveform according to the pitch pulse amplitude information by considering a predetermined number of waveforms peripheral to a peak position of the lost frame's CELP decoded excitation signal, and convolutes a pitch pulse waveform into a time axis which has been amplitude-adjusted according to the pitch pulse position information. A sound source signal corrector adds or replaces the pitch pulse waveform convoluted into the time axis to the lost flame decoded sound source signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.