Deflicking

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In video processing, deflicking is a filtering operation applied to brightness flicker in video to improve visual quality. The flicker effect can be seen when camera framerate and lighting frequency are not adjusted or in video digitized old film. The filter aims to improve the appearance of movies.

In electronics engineering, video processing is a particular case of signal processing, in particular image processing, which often employs video filters and where the input and output signals are video files or video streams. Video processing techniques are used in television sets, VCRs, DVDs, video codecs, video players, video scalers and other devices. For example—commonly only design and video processing is different in TV sets of different manufactures.

Brightness perception of light level

Brightness is an attribute of visual perception in which a source appears to be radiating or reflecting light. In other words, brightness is the perception elicited by the luminance of a visual target. It is not necessarily proportional to luminance. This is a subjective attribute/property of an object being observed and one of the color appearance parameters of color appearance models. Brightness refers to an absolute term and should not be confused with Lightness.

The main idea is to smooth image brightness between series of the same scene frames.

The deflicking filter is usually used in video camera (for normalizing picture), used for postprocessing of captured video, and for restoration of video from old films.

The term post-processing is used in the video/film business for quality-improvement image processing methods used in video playback devices,, and video players software and transcoding software. It is also commonly used in real-time 3D rendering to add additional effects.


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