Hybrid variable length coding method for low bit rate video coding
US7454076B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 15, 2004 |
| Grant date | Nov 18, 2008 |
| Priority date | — |
| Expiry date | Dec 9, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/91
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and an apparatus of image compression, and a memory to store a data structure for compression. The method includes, for an ordered series of quantized coefficients of a transform of an image block, forming from the series events each with a run of non-zero-valued coefficients in a first contiguous region defined by a breakpoint, a run of zero-valued coefficients in the first region, or a run of zero-valued coefficients in a second region defined by the breakpoint. The breakpoint defines the first region and a second continuous region in the series. Codewords are formed for each runlength of non-zero-valued and zero-valued coefficients in the first region according to a first and a second coding method, respectively, and a codeword is formed for the non-zero amplitudes according to a first amplitude coding method. The runlengths of zero-valued coefficients in the second region are encoding using a third coding method.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.