Avidemux Won't "Search next black frame"

[Danette]

I am trying to use the "Search next black frame" feature, but the videos are searched and black frames are never found. The search stops once the end of the video is reached. However, there are plenty of black frames throughout the video. Is there a trick to getting this feature to work correctly?

[StainlessS]

Is there not some threshold to set, below which is considered black ? [dont think I've ever used AviDemux)].

In VDub Menu/Options/Preferences/[scene], sets threshold for the scene change detection [little red/green arrows below the timeline], perhaps similar for AviDemux.

EDIT:
Do you just want to delete black frames ? :- https://forum.doom9.org/showthread.php?t=175158

Or to tween single black/white frames,
TweenFrames():- https://forum.doom9.org/showthread.php?p=1668968#post1668968

EDIT:
Or to tween single black/white frames
This update to above linked post, "simultaneouly fix White and Black flashes when -ve FlashThresh".
TweenFlashFrames (or fields)
https://forum.doom9.org/showthread.php?p=1671077#post1671077