Methods and systems for compressing a video stream with minimal loss after subsampled decoding
US7627038B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 19, 2004 |
| Grant date | Dec 1, 2009 |
| Priority date | — |
| Expiry date | Dec 18, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/59
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Transcoding of a video stream to reduce the size of the video stream with little, if any, loss in video quality after subsampling. After accessing a video stream of video pictures (i.e., video frames or fields), the blocks of the video picture are each subject to matrix pre-multiplication and post-multiplication. Such matrix multiplication does degrade the video quality if subsampling was not to occur. However, the pre-multiplication and post-multiplication matrices are calculated based on the subsampling matrices that will be used to ultimately subsample the video stream such that after subsampling eventually occurs, the matrix multiplications result in minimal loss of video quality.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.