Variable frame rate (or VFR) is a term in video compression for a feature supported by some container formats which allows for the

frame rate Frame rate (expressed in or FPS) is the frequency (rate) at which consecutive images ( frames) are captured or displayed. The term applies equally to film and video cameras, computer graphics, and motion capture systems. Frame rate may also ...

to change actively during video playback, or to drop the idea of frame rate completely and set an individual timecode for each frame. VFR is especially useful for creating videos of slideshow presentations or when the video contains large amounts of completely static frames, as a means of improving compression rate, or if the video contains a combination of 24/25/30/50/60 FPS footages and the creator or editor of the video wishes to avoid artifacts arising from framerate-conversion. In video recording, a lowered framerate may be preferred in darker environments to extend the exposure time per frame, allowing the

image sensor An image sensor or imager is a sensor that detects and conveys information used to make an image. It does so by converting the variable attenuation of light waves (as they pass through or reflect off objects) into signals, small bursts of c ...

to capture more light, which results in brighter footage.

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