Auto generate MKV chapters using FFmpeg BlackDetect filter
Works best with TV Shows that have had commercials stripped out and leave a noticable black screen.
1/2 hour shows typically produce 4 or 5 chapters marks. 1 hour shows maybe 8 or 9 chapters.

Example without any options that use the default blackdetect seconds value (.5)
FFchap "Blue Bloods - S06E02 - Absolute Power.mkv"

Example using the -s option for custom blackdetect value
FFchap -s 1.5 "Blue Bloods - S06E02 - Absolute Power.mkv"

mkvpropedit & ffmpeg are required

If you have chapters in the mkv file they will be replaced.
Target files are NOT re-encoded and mkvpropedit is instantaneous.
720p files are processed resonably quick <1 min, 1080p is noticeably longer.