so i decided to migrate my PMS back to my mac simply because i like my mac mini better than my windows server. so, i've set it up to automatically transcode or remux all my incoming media to mp4. since rebuilding my library i've noticed that my tv show episodes no longer have the nifty little thumbs that is a screen grab of the episode, which is great for reference. now all i have is the season poster or the tv show poster for each episode. on my windows server i had the option to "Generate video preview thumbnails" enabled, but i have it disabled on my mac because i don't want the extra cpu load, don't want the wasted space, and the mp4 files work perfectly in plex showing a thumb when scrubbing through a episode.
so, how does plex generate the thumbs for each episode? is that from metadata pulled from the interwebs or from processing the PMS does at some point? i haven't been able to find a answer or solution to remedy this.