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. 07, 1999
Filed:
Jan. 14, 1997
Hiroshi Yamagata, Kanagawa, JP;
Kenji Watanabe, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
An aspect ratio discrimination apparatus and an image display apparatus which prevent a malfunction in discrimination of a first video signal for exhibition of a normal image and a second video signal for exhibition of a horizontally elongated image. An upper-lower portion average brightness calculation section receives an input video signal to form an image and calculates an average brightness of upper and lower portions (black band portions) of the image. An upper-lower portion brightness difference calculation section calculates differences between the average brightness and brightness levels of the black portions of the image. A high brightness difference rate detection section discriminates whether or not the rate of the area of portions in the black portions in which the brightness differences are higher than a predetermined level is higher than a predetermined value. When the rate of the area is higher than the predetermined value, it is discriminated that the video signal inputted to the aspect ratio discrimination apparatus or the image display apparatus has the aspect ratio of 4:3.