Methods and apparatus for progressive transmission of subband images
US6904091B1 · kind B1 · utility
Assignees
Inventors
Key dates
| Filing date | Mar 24, 2000 |
| Grant date | Jun 7, 2005 |
| Priority date | — |
| Expiry date | Mar 24, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/64
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Images are subband transformed to create a plurality of subband images. Each subband image includes a plurality of pixels. Each pixel is represented by a plurality of bits with each bit associated to a certain quantization level. Encoding of an image requires scanning essentially all the bits of essentially all the pixels of the image. While scanning in a particular order, one can exploit dependencies within groups of bits consecutively scanned for encoding purposes. Thus, bits of groups can be encoded together. In a subband and transformed image, the scanning order or scanning curve is defined by indicating in which order the system traverses the several subbands and the several quantization levels. One method is characterized in that the set of scanned bits which will be encoded together, and which thus form a group, bits of at least two different sub-images and at least two different quantization levels are recognized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.