Method and encoder for constrained soft-decision quantization in data compression
US8675726B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 18, 2010 |
| Grant date | Mar 18, 2014 |
| Priority date | — |
| Expiry date | Nov 20, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/61
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of encoding a video using constrained soft-decision quantization. The soft-decision quantization includes first performing hard-decision quantization to obtain hard quantized coefficients and, then, obtaining a soft quantized coefficient using a rate-distortion calculation over a search range of quantization levels for a transform domain coefficient, wherein the search range of quantization levels for that transform domain coefficient is constrained within a number of quantization levels of a corresponding hard quantized coefficient. The search range may be based upon a fixed threshold, the coefficient position, the hard quantized coefficient magnitude, a threshold value less accumulated distortion, or other factors, including combinations of these factors. The accumulated distortion may be measured by an L1 norm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.