Still Frame

A still frame is a single static image ("frame") taken from a film or video, which are kinetic (moving) images. Still frames are also called freeze frame, still image, video prompt, preview or misleadingly thumbnail, keyframe, poster frame, or screen shot/grab/capture/dump. Freeze frames are widely used on video platforms and in video galleries, to show viewers a preview or a teaser. Many video platforms have a standard to display a frame from mid-time of the video. Some platforms offer the option to choose a different frame individually.

Video and film artists sometimes use still frames within the video/film to achieve special effects, like freeze-frame shots or still motion.

For criminal investigations it has become a frequent use to publish still frames from surveillance videos in order to identify suspect persons and to find more witnesses. Videos of the 9/11 attacks have been often discussed frame-by-frame for various interpretations. For medical diagnostics it is very useful to watch still frames of Magnetic resonance imaging videos.

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Wikipedia