Media Preview Generator: Faster Previews for Plex, Emby, and Jellyfin

What it is for

Media Preview Generator is designed for people running Plex, Emby, or Jellyfin at home. It runs as a Docker container and can begin work when Sonarr or Radarr imports a file. Its main jobs are generating seek-bar preview thumbnails and attempting to create Skip Intro and Skip Credits markers. When the same file exists on several servers, the project describes a workflow that decodes it once and writes each server’s required format.

The project is a reasonable fit for self-hosters who want previews soon after an import, operate more than one media server, or do not want to wait for a server’s scheduled background generation. The README also says it is unnecessary when a server’s built-in generator already keeps up with the library.

Documented features

The application accepts webhooks from Sonarr, Radarr, Sportarr, Tdarr, FileFlows, Plex, Emby, and Jellyfin. It also supports Recently Added polling, cron and interval schedules, and manual generation by searching a server or browsing media folders. Jobs can retry while a server is indexing a new file, and current previews can be skipped.

GPU processing is the preferred path but is not mandatory. The README lists NVIDIA, Intel, and AMD GPUs on Linux, plus NVIDIA on Windows through WSL2. If a file cannot be decoded by the GPU, the same worker can retry it on the CPU. The project also supports key-frame skipping and documents tone mapping for HDR10, HLG, HDR10+, and the HDR10 layer of Dolby Vision profiles 7 and 8. Dolby Vision Profile 5 requires a GPU with a hardware Vulkan driver.

Output is adapted to each server: BIF files in Plex’s data directory, BIF files next to videos for Emby, and Jellyfin trickplay tiles. Intro and credit detection can use chapters, online databases, a season’s theme song, or the credit roll. When confidence is insufficient, the project says it waits for review rather than submitting a guess. This feature must be enabled per server and has additional service requirements.

Deployment limits and checks

The basic requirements are Docker, network access from the container to the media server, and write access to the destination for previews. Plex writes to its data directory. Emby and Jellyfin commonly write beside the video in their default layouts, so those media mounts generally need to be read-write. A GPU is optional; when used, the host needs the relevant driver, and the README specifically calls out NVIDIA Container Toolkit for NVIDIA on Linux.

Integration prerequisites matter. Plex marker functionality requires Plex Pass and has server/viewer conditions. Jellyfin requires the Media Preview Bridge plugin. The supplied README contains differing Jellyfin wording—“10.11 or 12.0” in one section and “10.10 or newer” in quick start—so operators should verify the current documentation against their installation. Emby requires its corresponding plugin, while Skip Intro additionally requires Emby Premiere. The sources do not provide a universal hardware baseline, compatibility guarantee, or processing-speed claim.

Avoid duplicate work after deployment. Check each media server’s own preview-generation settings; the README warns that disabling Jellyfin trickplay can delete tiles written by this application. Official release 4.4.2 corrected the thumbnail-quality tooltip: lower values represent sharper output, and the default remains 4. The project is MIT-licensed, but that does not establish security guarantees for media files, credentials, or network exposure. Restrict access, protect authentication configuration, and validate mounts and plugins with a small library before wider rollout.

Sources

• GitHub repository metadata
• Project README
• Official release
• Official project page

Sources checked: 2026-09-28