ChapSnap
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Fade-out then Fade-in is not detected as a Scene Change
The algorithm used is just a simple threshold on the scene change score calculated by FFmpeg.
Since a Fade-out doesn't wildly differ from its previous frame, the entire transition occurs without detection. Similarly, the Fade-in works out the same.
This is only a problem when a Fade-out is met with a Fade-in directly after. A Fade-out to then a jump-cut works fine. A jump-cut to a Fade-in also works fine.
The only fix I can think of is to remove the frames after the start of the transition, and before or on the end of the transition. This results in what looks to be a jump cut instead of a fade transition and the algorithm by FFmpeg with the threshold will pick it up as a Scene Change. However, doing so in an automated way is not such an easy task to pull off.