Noise reducing system
First Claim
1. A noise reducing system comprising first circuit means for detecting a variation of a picture from an input picture signal and a past picture signal by mixing said signals with a selectively variable ratio;
- second circuit means for controlling the mixing ratio between the input picture signal and the past picture signal in response to an output signal of said first circuit means; and
memory circuit means for delaying the output of said second circuit means a fixed time period to provide said past picture signal;
said second means comprising movement detector circuit means for detecting displacement of the variation of the picture per frame from the output of said memory circuit means and the output of said first circuit means, and movement compensator circuit means coupled between said memory circuit means and said first circuit means and controlled by an output of said movement detector circuit means for generating and providing to the first circuit means a past picture signal which corresponds to the same area as the input picture signal.
1 Assignment
0 Petitions
Accused Products
Abstract
A noise reducer wherein, depending upon the magnitude of a difference signal between an input television signal at the present time and a television signal recorded in a frame memory and with noise reduced, the mixing ratio between the present-time input signal and the television signal obtained from the frame memory is varied, and a part of the mixed signal is applied to the frame memory while the other part is used as a television signal with noise reduced; a noise reducing system wherein, in order to make the reduction of noise possible even for a moving object, a movement of a picture in one frame time is detected, the output of the frame memory is compensated for with the movement, and depending upon the magnitude of a difference signal between the present-time input television signal and the movement compensated output signal of the frame memory, the mixing ratio between the present-time input television signal and the compensated output signal of the frame memory is varied.
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Citations
5 Claims
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1. A noise reducing system comprising first circuit means for detecting a variation of a picture from an input picture signal and a past picture signal by mixing said signals with a selectively variable ratio;
- second circuit means for controlling the mixing ratio between the input picture signal and the past picture signal in response to an output signal of said first circuit means; and
memory circuit means for delaying the output of said second circuit means a fixed time period to provide said past picture signal;
said second means comprising movement detector circuit means for detecting displacement of the variation of the picture per frame from the output of said memory circuit means and the output of said first circuit means, and movement compensator circuit means coupled between said memory circuit means and said first circuit means and controlled by an output of said movement detector circuit means for generating and providing to the first circuit means a past picture signal which corresponds to the same area as the input picture signal. - View Dependent Claims (2, 3, 4, 5)
- second circuit means for controlling the mixing ratio between the input picture signal and the past picture signal in response to an output signal of said first circuit means; and
Specification