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:
Apr. 03, 2007
Filed:
Mar. 28, 2002
Tetsuro Shiota, Takatsuki, JP;
Tetsuro Shiota, Takatsuki, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
In gray-scale correction where extension to a dynamic range is performed based on a maximum value and a minimum value of a video luminance signal, sufficient correction effects cannot be obtained in some displayed images. Therefore, a histogram detecting circuit (), a maximum value detecting circuit (), and a minimum value detecting circuit () respectively detects, for each field, a maximum value (Kmax) and a minimum value (Kmin) in a detection WINDOW set in a screen, and distribution information in a gray-scale direction. The detected maximum value (Kmax) and minimum value (Kmin) are respectively corrected by a maximum value correcting circuit () and a minimum value correcting circuit () based on the output results of the histogram detecting circuit (), and output as a corrected maximum value (Lmax) and a corrected minimum value (Lmin). Based on these corrected maximum value (Lmax) and a corrected minimum value (Lmin), an input video luminance signal is corrected. Thus, it is possible to obtain optimal effects of gray-scale correction in accordance with a scene.