Apparatus and method for encoding zerotrees generated by a wavelet-based coding technique
US6483946B1 · kind B1 · utility
Assignees
Inventors
Key dates
| Filing date | Oct 24, 1996 |
| Grant date | Nov 19, 2002 |
| Priority date | — |
| Expiry date | May 2, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/647
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Apparatus and method for encoding zerotrees in a wavelet-based coding technique. The method uses a depth-first pattern for traversing the zerotree, i.e., each branch of the tree, from parent to child to grandchild and so on, is fully traversed before a next branch is traversed. The depth-first tree traversal pattern is used to quantize the coefficients of the tree as well as to assign symbols to the quantized coefficients. The method assigns one of three symbols to each node: ZEROTREE ROOT, VALUED ZEROTREE ROOT, and VALUE. By using three symbols and the efficient tree traversal pattern, the method is substantially more efficient at encoding a zerotree than the prior art. Additionally, this concept is applied to the encoding of “vector” zerotrees.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.