Batch cut of videos

Community, I have a bunch of captured videos that have a trailing end because I regularly forget to stop the recording. Is there a quick and convenient way to batch cut them from where the video turns black or better yet at least >50% black? Related: is there a way to filter videos without an audio track or better yet is silent most of the time? Sometimes I botch the audio setup; without it, the video of the meeting or workshop is meaningless.

FFMPEG will do that: video - How to trim out black frames with ffmpeg on windows? - Video Production Stack Exchange