Method and apparatus for visual pattern image coding
US5144688A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 1990 |
| Grant date | Sep 1, 1992 |
| Priority date | — |
| Expiry date | Mar 23, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/91
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An improved method for coding and decoding digital images by partitioning images into blocks and coding each image separately according to visually significant responses of the human eye. Coding is achieved by calculating and subtracting a mean intensity value from digital numbers within each block or partition and detecting visually perceivable edge locations within the resultant residual image block. If a visually perceivable edge is contained within the block, gradient magnitude and orientation at opposing sides of the edge within each edge block are calculated and appropriately coded. If no perceivable edge is contained within the block, the block is coded as a uniform intensity block. Decoding requires receiving coded mean intensity value, gradient magnitude and pattern code, and then decoding a combination of these three indicia to be arranged in an orientation substantially similar to the original digital image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.