Deleting Thumbnail Previews

[SpartacusIam]

I'm curious how one would delete all thumbnails generated by this tool for a given library the way one can in the advanced library settings in Plex? I don't have a need right now but I've done this multiple times over the years and can see myself doing this again in the future.

[stevezau]

This tool doesn't support deleting previews. I blieve Plex will handle the cleaning up old bundles tho. At least it will if you run the bundle cleanup job.

[stevezau]

Are you just trying to delete all previews for a library in plex or all previews generated by this tool... and why ?

[SpartacusIam]

Plex thumbnails are disabled and don't exist. Only ones that exist are from this tool. I'm just trying to plan for how I would delete all thumbnails generated by this tool in the future if need be. Say if I didn't want them taking up space anymore.

[stevezau]

Any reason you just don't go to Plex > Server > Troubleshooting and clean bundles. that should remove them.

[SpartacusIam]

Are you saying that any time one runs clean bundles it will delete all the thumbnails generated by this app? I thought that only cleaned up files for media that no longer exists.

[stevezau]

You said "Plex thumbnails are disabled and don't exist.". So in that case, i'd expect plex should clean up the bundles with previews. But i am not 100% sure.. have you tried it?

[SpartacusIam]

Maybe we're talking past each other. In Plex I have this disabled and Plex never generated any thumbnails itself.

I've only generated thumbnails with your app. I'm asking how I might delete those thumbnails in the future if I didn't want them anymore. I sure hope that simply cleaning bundles wouldn't remove the 200+GB of thumbnails that your app has generated for me.

[stevezau]

Sorry, I muddled the earlier answer.. let me be clearer.

About this app: it does not delete preview thumbnails, and it doesn't track the ones it generates. It writes index-sd.bif to the exact same path Plex does
(Media/localhost/<hash>/Contents/Indexes/index-sd.bif), so once the file is on disk it's indistinguishable from one Plex created itself.

About Plex's behaviour, since you'd be relying on Plex to clean up:

• Disabling the "generate video preview thumbnails" library setting only stops new ones being made. It does not delete existing BIFs.
• Clean Bundles only removes bundles for media that no longer exists in the library. It won't touch BIFs for media that's still there — you were right to be sceptical.
• The supported way to remove them for an existing library is Library → Edit Library → Advanced → "Delete Preview Thumbnails". Plex deletes the BIFs in the background; running Clean Bundles + Optimize
  Database afterwards helps reclaim disk space (it can take a maintenance cycle to fully free up).
• Manually deleting the .bif files under Media/localhost/.../Contents/Indexes/ is also fine; run Clean Bundles afterwards.

Either way it's a Plex-side operation, not something this tool drives.

[SpartacusIam]

Ok perfect. I didn't know that the "Delete Preview Thumbnails" button in Plex would delete previews generated by this app. That's great that it does. Thank you for clearing that up!

[stevezau]

Yep, this app just does exactly what Plex does when it generates the preview files.