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. 05, 1989
Filed:
Jun. 21, 1988
Yasutoshi Matsuo, Kawasaki, JP;
Abstract
A noise reduction circuit for use in a video signal recording and/or reproducing apparatus for eliminating noise components from an input luminance signal comprises a high pass filter circuit for extracting a high frequency signal component from the input luminance signal, a first limiter circuit for limiting the high frequency signal component at a first limiting level, a multiplier circuit for determining the degree of preemphasis and/or deemphasis by multiplying a predetermined coefficient to the limited signal, summing and subtracting circuits respectively for adding and subtracting the output signal of the first amplifying means to and from the input luminance signal, and a feedback loop for feeding back the output signal of the high pass filter circuit to its input port. The feedback loop comprises a second multiplier circuit which modifies the amplitude of the signal passing therethrough by a second level which is set substantially higher than the first level of the first limiter circuit.