[Feature] On demand thumbnail and transcoding

The feature

Hello,

I'd like to see an option to disable thumbnail and transcode creation and to see support for on demand thumbnail creation. I run immich on a 32 core threadripper with an RTX 3080 GPU, so transcoding in real time isn't difficult for my system.

I have searched around, and the closest discussion similar to this is however my request is that we save disk space by not transcoding and creating thumbnails, but doing so in real time. Maybe the thumbs and encode-video folder can be periodically flushed of files older than a day, that way we can use those folders to temporarily store the needed thumbnail and transcode in a way that's similar to cache in that it gets cleared over time.

The reason I'm wondering about this is currently both of these folders add up to about 400 GB, which is not insignificant even though I have 25 TB free disk space.

Platform

• Server
• Web
• Mobile