Jellyfin does support pre-generating image previews (“Trickplays”) for media that can be download by the client. That allows for clients to show previews while seeking much faster.

Support Trickplay for Jellyfin

NC_Bullseye Split this topic October 6, 2024, 4:44pm 2

Topic		Replies	Views
Support Jellyfin Trickplay feature Suggestions	7	14447	June 5, 2025
Jellyfin 10.10.x intro/outro skip support Suggestions	2	426	October 17, 2024
"List mode" for Jellyfin Suggestions	2	31	May 27, 2025
Plex vs. Jellyfin? Streaming & Network	4	1550	July 30, 2020
Live TV Streaming for JellyFin Suggestions	2	106	April 3, 2025