Digital image coding system having self-adjusting selection criteria for selecting a transform function
US6618509B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 9, 2001 |
| Grant date | Sep 9, 2003 |
| Priority date | — |
| Expiry date | Apr 9, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/61
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a digital signal processing system, a method for selecting a transform function to apply to an input signal based on characteristics of the signal, and for self-adjusting criteria which are used in selecting a transform function to apply to a subsequent signal. Characteristics are obtained from the signal. The characteristics are compared to adjustable criteria which are used in selecting a transform function. Differing criteria are maintained for the different selectable transform functions. A record is maintained of transform functions selected and the particular characteristics that caused the selection. Based on the ability of a transform function to minimally define the coded signal, an inverse transform function is selected to decode the signal. The criteria used in selecting a transform function to apply to a subsequent signal are adjusted based on a quality measure of the decoded signal and the record of selected transform functions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.