Switching distortion metrics during motion estimation
US8155195B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 7, 2006 |
| Grant date | Apr 10, 2012 |
| Priority date | — |
| Expiry date | Aug 17, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/567
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Techniques and tools for switching distortion metrics during motion estimation are described. For example, a video encoder determines a distortion metric selection criterion for motion estimation. The criterion can be based on initial results of the motion estimation. To evaluate the criterion, the encoder can compare the criterion to a threshold that depends on a current quantization parameter. The encoder selects between multiple available distortion metrics, which can include a sample-domain distortion metric (e.g., SAD) and a transform-domain distortion metric (e.g., SAHD). The encoder uses the selected distortion metric in the motion estimation. Selectively switching between SAD and SAHD provides rate-distortion performance superior to using only SAD or only SAHD. Moreover, due to the lower complexity of SAD, the computational complexity of motion estimation with SAD-SAHD switching is typically less than motion estimation that always uses SAHD.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.