Variable length coding method and apparatus
US6917651B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 23, 2000 |
| Grant date | Jul 12, 2005 |
| Priority date | — |
| Expiry date | May 10, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/89
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A variable length coding method and apparatus is provided. The variable length coding method includes the steps of (a) selecting predetermined macroblocks from among the previous macroblocks of a macroblock to be coded in a current frame, (b) analyzing the occurrence statistics of symbols with respect to the selected macroblocks, (c) resetting a mapping relationship based on the analyzed occurrence statistics of symbols, and (d) variable length coding a current macroblock based on the reset mapping relationship. The variable length coding method dynamically varies the mapping relationship between symbols and bit patterns based on the occurrence statistics of the symbols, thereby reducing the amount of bits generated when coding images of the same picture quality.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.