Shot transition detection

Cut detection is a field of computer science. Its aim is the automated detection of shots in digital video.

Use

Cut detection is a useful tool for post-production of digital video on computers as the editor does not have to search for scene changes manually. Moreover cut detection is an important issue of automated archiving of digital video. In that field, the aim is to automatically create indexes for huge video archives. Cut detection enables the automated selection of representative preview images for each scene.

Hard cuts and soft cuts

Cut detection distinguishes hard cuts from soft cuts. While with a hard cut, one shot is replaced abruptly by another shot (e. g. , with a soft cut one shot in some way slowly fades out while another shot slowly fades in (e. g. dissolve (film)).

Many modern algorithms have excellent performances recognizing hard cuts and even such obvious ones as histogram differences (see below), basing on basic methods of image processing deliver good results. Yet with soft cuts, most algorithms eiher fail in recognizing them or produce false hits. The slow changing of the complete image content is often interpreted falsely as movement of objects within the scene.

An introduction to film editing and an exhaustive list of shot transition techniques can be found at film editing.