Image processing apparatus
US5384869A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 7, 1992 |
| Grant date | Jan 24, 1995 |
| Priority date | — |
| Expiry date | Oct 7, 2012 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N19/635
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Image processing apparatus is described for filtering a digital representation of a raster scanned image into a plurality of sub-bands in the two-dimensional spatial frequency domain, the resolution of the raster scanned image in a first direction (usually the horizontal direction) being greater than the resolution of the raster scanned image in a second direction (usually the vertical direction). The image processing apparatus has a decimation filter means comprising a number of multi-tap digital decimation filters for spatial filtering in the first and second directions. The mean of the filter lengths of the filters used for filtering in the first direction is greater than that of the filters used for filtering in the second direction. Complementary interpolation apparatus for reconstructing the image from the plurality of sub-bands is also described.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.