Truncated subband coding of images
US4817182A · kind A · utility
92Cited by
6References
9Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 4, 1987 |
| Grant date | Mar 28, 1989 |
| Priority date | — |
| Expiry date | May 4, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/635
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Image data is analyzed in a number of iterated analysis procedures, using two-dimensional quadrature mirror filters to separate low-pass spatial filter response component and three differently oriented high-pass spatial filter response components, which filter response components are decimated in both dimensions. The high-pass filter response components are coded as is. The low-pass filter response component is coded as is only in the last iteration; in the earlier analysis procedures the low-pass filter response component provides the input data for the secceeding analysis procedure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.