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:
Oct. 21, 2003
Filed:
Mar. 09, 2001
Abstract
A gradation correction circuit comprises: an arithmetic means ( ) for operating an output value corresponding to each broken point of a broken line in a vertical blanking period; a level detection circuit for identifying a size relation between each broken line point which is an input value corresponding to each broken point and an input video signal, and calculating a difference between the input video signal and each broken line point; and a correction means ( ) for selecting a gradient of the broken line on the basis of the result identified by the level detection circuit , and performing gradation correction of the input video signal on the basis of the selected gradient of the broken line, the output value calculated by the arithmetic means, and the difference calculated by the level detection circuit, wherein the arithmetic means and the correction means share a number of circuits ( ). Therefore, there is provided a gradation correction circuit where video correction with high precision can be realized without using a memory storing a lookup table, or without increasing a circuit scale.