Transcoder for scalable multi-layer constant quality video bitstreams
US6925120B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 2001 |
| Grant date | Aug 2, 2005 |
| Priority date | — |
| Expiry date | Mar 2, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N21/4347
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method codes an output bitstream of an input video so the decoded output bitstream has a constant perceived quality. A base layer bitstream having a constant bit-rate is generated from the input video, and an input enhancement layer bitstream is generated from a difference between the input video and the base layer bitstream. Rate and distortion characteristics are extracted from the base layer bitstream and the input enhancement layer bitstream, and an output enhancement layer bitstream having a variable bit-rate is generated from the input enhancement layer bitstream according to the rate and distortion characteristics. The base layer bitstream and the output enhancement layer bitstream, in combination, form an output bitstream having a variable bit-rate and a constant distortion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.