Is there any free utility which allows to split video files (.avi .mpg etc) by either positioning a slider and/or by setting the time/frame to split at?
MKVToolNix - https://mkvtoolnix.download
This is the one you want, super easy, splits by time and can split by multiple times at once if you use commas.
Super handy, can also merge vids as well.
I listed the pros and contras of mkvtoolnix here (the others I listed have contras at well) https://forums.macrumors.com/thread...ncatenate-mts-snippets.2061572/#post-24916085 but it is probably the best recomended. I planned to use it, too. I am just a bit hesitating, because there is no preview in Finder when you click on the movie's icon later.