Rate control of scalably coded images
US7668380B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 18, 2005 |
| Grant date | Feb 23, 2010 |
| Priority date | — |
| Expiry date | Jan 15, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/63
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of rate-control for a sequence of scalably coded images having transform coefficients partitioned into coding units coded in a plurality of quality increments having respective significance values. The method defines subsets each having one or more coding units, at least one image contributing at least one coding unit to two or more subsets. A list of requirements (LOR) is set having a least one entry associated with each subset. The significance values are used to select quality increments to construct an admissible codestream that satisfies the LOR on the subsets. The quality increments may be selected to achieve high quality for different subsets subject to size requirements in the LOR. For certain requirements, the codestream will also exhibit approximately constant reconstructed image quality. The quality increments may also be selected to achieve small compressed sizes for different subsets subject to quality requirements in the LOR.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.