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:
Jan. 06, 1998
Filed:
Aug. 29, 1996
Hidefumi Okada, Osaka, JP;
Sanyo Electric Co., Ltd., Moriguchi, JP;
Abstract
A gamma correction circuit including a first look-up table in which minimum values of differences between output levels of a gamma correction curve and output levels of a straight line in respective sections formed by dividing a range from a minimum input level to a maximum input level into sixteen are stored. Furthermore, data of differences between the output levels of the gamma correction curve and levels obtained by adding the minimum values to the output levels of the straight line in the respective sections are stored in respective second look-up tables of sixteen. Then, one of the minimum values is read-out from the first look-up table according to upper four bits of input video data, and one of the second look-up tables is selectively enabled by the upper four bits, and data stored in the selected second look-up table is read-out in accordance with lower six bits of the input video data. Outputs from the first and second look-up tables are added to each other so as to output gamma correction data which is then added to the input video data, whereby a gamma characteristic of the input video data is corrected.