Compressing video isn't going to work unless you reencode it, so no
this post was submitted on 23 May 2024
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Thank you, I realised that I'd need to reencode transparently. How would I do that?
You could use BTRFS, ZFS or BcacheFS to do compression on the filensystem level, but it's not gonna compress video files or other already compressed media.
Isn't that video stream already compressed? Or you want to convert it using another codec/bitrate?
Thank you, I realised that I'd need to reencode transparently. How would I do that?
I do something similar for my property's exterior cameras, which are streamed to my VPS in 'real-time'.
You will need to re-encode the footage - videos are already pretty well compressed, so traditional compression methods like 7z (lzma), gz, zip etc being layered on top can't compress them further.
For your solution, I'd probably run a find every minute w/ cron to look for these files in a staging/watch folder, move them to another folder so they aren't picked up on the next run, then re-encode with ffmpeg. Do note that when you re-encode footage, you always lose quality, even if you're on a high quality preset.
I have a feeling that the Handbrake project can do this with a watch folder though, so might be worth looking into that. After a quick search this looks easier to setup than my solution:
https://github.com/HandBrake/HandBrake
https://github.com/shannah/handbrake-watcher
Thank you, this is exactly my use-case, along with some live streaming.
However,
- How are you running a find command on a warch folder with continuously streaming video? I believe the IPC process has to end (system has to finish writing to a file) for post-processing (reencoding) to take place? That's why I wanted to do this transparently, since I have no local storage to speak of to maintain a watch folder/cache.
- Thanks for the reencoding solution, I'll take a look at handbrake
If you want a live conversion and can't afford the >100$ it would cost to grab an ssd for a scratchdisk, you might also look into using vlc to grab the video stream from source camera, and encode it out to somewhere else, such as a webserver.
https://wiki.videolan.org/Documentation:Streaming_HowTo/Receive_and_Save_a_Stream/
You might also need a script to make sure it's always up.
Alternatively, there's a good chance that zoneminder will be able to do what you want with just a little tinkering. https://zoneminder.com/
Is using btrfs an option? Offer transparent compression at FS level
you mean like piping to gzip or so?