Single chip motion wavelet zero tree codec for image and video compression
US6381280B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 29, 1998 |
| Grant date | Apr 30, 2002 |
| Priority date | — |
| Expiry date | May 29, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/647
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A motion wavelet transform zero tree codec achieves high compression and is implemented in hardware of modest size and at very low cost. A wavelet transform is combined with a tree walk technique for encoding the resulting wavelet coefficients. A 2-6 wavelet transform is used. Wavelet coefficients from the transform are represented in a pyramid of wavelet coefficients. An array of zero trees are formed from the pyramid to hold the wavelet coefficients, one coefficient to each node. Significance values for each node are calculated to assist with the tree walk and encoding. Each zero tree is traversed to produce an output of encoded bits. Encoded bits are output directly during the tree walk.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.