Zero pass JPEG bit rate controller
US8634639B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 2, 2012 |
| Grant date | Jan 21, 2014 |
| Priority date | — |
| Expiry date | Jul 17, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/186
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Embodiments are directed towards compressing an image to substantially a preset file size using statistical information obtained from a single subset of the image and an initial compression of the single subset. A representative subset portion of the image is selected based in part on a clustering analysis of the image. The representative subset is then compressed, in one embodiment, twice, in order to obtain statistics useable for the entire image. A scale factor is then determined that may be used in the quantization and for creating a Bit Rate Control (BRC) curve that represents an amount of accumulated bits per Minimal Codec Unit (MCU). During the compression process, the BRC curve is used to prevent accumulating bits from over shooting a final preset file size target.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.