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:
Nov. 24, 1987
Filed:
Feb. 17, 1987
Hidetoshi Ozaki, Chofu, JP;
Victor Company of Japan, Ltd., Yokohama, JP;
Abstract
A noise reduction circuit for video signal comprises first through third circuits each for obtaining from an input video signal a high frequency component including a noise component and for limiting large amplitude parts thereof, where a filter part of the second circuit has an impulse response characteristic wherein an amplitude increases or decays with time and is complementary to that of a filter part of the first circuit and a filter part of the third circuit has an impulse response characteristic which is essentially a combination of the two impulse response characteristics, and a fourth circuit for carrying out a subtraction between the input video signal and an output signal of the first circuit so as to obtain a first signal which is substantially eliminated of the noise component except for a noise component and distortion remaining at parts in vicinities of rises and falls in the video signal caused by the amplitude limitation carried out in the first circuit, carrying out a subtraction between output signals of the second and third circuits so as to obtain a second signal which includes the noise component and the waveform distortion of the first signal with an inverted phase, and for adding the first and second signals so as to produce an output video signal which has been substantially eliminated of all the noise component.