Digital correction circuit and image data processing apparatus equipped with a digital correction circuit
US6278496A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 8, 1998 |
| Grant date | Aug 21, 2001 |
| Priority date | — |
| Expiry date | Oct 8, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2320/066
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In the .gamma. correction circuit, a crossover point arithmetic processing unit performs arithmetic processing for each region on crossover points y in the output data direction of a .gamma. correction crossover line based on a plurality of slope data A respectively specified for each of a plurality of regions and crossover point positions X in the input data direction set in advance. A 5-to-4 encoder and a selector select one of a plurality of slope data A respectively specified for each of a plurality of regions and one result B of the results y of arithmetic processing on said crossover points based on the upper bits of input data, a flag encoder and another selector calculate the difference .DELTA.X from a crossover point position in the input data direction to the input data in the region to which input data belongs, and an arithmetic processing unit multiples the above difference .DELTA.X by the selected slope A, adds the multiplication result to the value of the selected crossover point position B in the output data direction, and outputs that value as a .gamma. correction value. Consequently, even if the number of crossover lines for digital .gamma. correction increases, ar…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.