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:
Aug. 22, 1989
Filed:
May. 18, 1988
Abstract
A noise reduction circuit for a video signal recording and/or reproducing apparatus comprises a high pass filter for extracting high frequency signal component form the input luminance signal, a limiter circuit for limiting the high frequency signal component, a multiplier for determining the degree of preemphasis and/or deemphasis by multiplying the limited signal, and summing and subtracting circuits respectively for adding and subtracting the high frequency signal component processed by the limiter circuit and the multiplier to and from the original luminance signal. The limiter circuit has an amplitude characteristic which changes a gradient so as to have a characteristic curve of at least three different gradient slopes interconnected in succession with an increase in amplitude of the signal supplied thereto.