Frequency domain parameter sequence generating method, encoding method, decoding method, frequency domain parameter sequence generating apparatus, encoding apparatus, decoding apparatus, program, and recording medium
US10332533B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Feb 16, 2015 |
| Grant date | Jun 25, 2019 |
| Priority date | — |
| Expiry date | Mar 11, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L25/12
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present invention reduces encoding distortion in frequency domain encoding compared to conventional techniques, and obtains LSP parameters that correspond to quantized LSP parameters for the preceding frame and are to be used in time domain encoding from coefficients equivalent to linear prediction coefficients resulting from frequency domain encoding. When p is an integer equal to or greater than 1, a linear prediction coefficient sequence which is obtained by linear prediction analysis of audio signals in a predetermined time segment is represented as a[1], a[2], . . . , a[p], and ω[1], ω[2], . . . , ω[p] are a frequency domain parameter sequence derived from the linear prediction coefficient sequence a[1], a[2], . . . , a[p], an LSP linear transformation unit (300) determines the value of each converted frequency domain parameter ˜ω[i] (i=1, 2, . . . , p) in a converted frequency domain parameter sequence ˜ω[1], ˜ω[2], . . . , ˜ω[p] using the frequency domain parameter sequence ω[1], ω[2], . . . , ω[p] as input, through linear transformation which is based on the relationship of values between ω[i] and one or more frequency domain parameters adjacent to ω[i].
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.