Methods and apparatus for generating and using visual error weights
US8351723B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 25, 2009 |
| Grant date | Jan 8, 2013 |
| Priority date | — |
| Expiry date | Nov 9, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/146
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A low complexity visual masking method used as part of an image encoding process is described. The method is suitable for use in JPEG2000 image compression systems. Control weights used for rate allocation are generated based on integer order moments of wavelet transformed coefficients corresponding to a codeblock. The novel rate allocation weight generation method can, and in some embodiments is, combined with an apriori rate allocation algorithm, where allocation of bits to different portions of images is controlled as a function of one or more generated weights. The methods and apparatus of the present invention have the effect of increasing errors in busy areas of an image where they tend to be less noticeable and allocating a higher number of bits to less busy areas than some other systems, e.g., systems which attempt to minimize a mean squared error under a constraint of a user selected output rate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.