The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 15, 1998
Filed:
Jun. 14, 1996
Naohiro Fujimura, Tokyo, JP;
Hitoshi Hasegawa, Tokyo, JP;
Takuji Kurashita, Tokyo, JP;
Hiroshi Onishi, Tokyo, JP;
Masayuki Tsuji, Tokyo, JP;
Yuuji Yamamoto, Tokyo, JP;
Shinji Takeuchi, Tokyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A video contrast enhancer enhances luminance contrast by dividing each video frame or field into blocks, calculating a mean luminance level for each block, selecting mapping functions on the basis of these mean luminance levels over a series of frames or fields, and mapping the video luminance levels according to the selected mapping functions. Color-saturation contrast is enhanced by modifying the amplitude of the modulated chrominance signal by the histogram equalization method, preferably by making a single linear modification in each period of the chrominance signal, so that color phase is not affected. For video signals with non-picture bands, these enhancements are preferably restricted to the picture area. If a black offset is present, it is preferably removed.