摘要 |
A recursive noise reduction system for a television system uses the spatial correlation in a frame difference signal derived by element-by-element subtraction of an incoming video signal from corresponding picture elements of a relatively noise-free stored video signal to redue noise in a video signal. The spatial correlation is used to suppress the components of the frame difference signal which are due to frame-to-frame changes in the video resulting from motion in the scene, thus producing a signal which contains substantially only the noise in the incoming video. The noise signal thus derived is subtracted from the incoming video signal to produce a noise-reduced output signal for display or recording. The noise-reduced output signal and the incoming video are added together in varying proportions according to the amount of scene-to-scene motion detected and the sum is stored for use in subsequent treatment of new incoming video. |