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Comment by jaggederest | Hacker News Reader

I've actually found my videos are not increasing as rapidly as I would expect. I've been reencoding in x265 and the file size difference is shocking. Right now I'm not ditching the existing original files but I may do that at some point, or just offload to a cloud service like Glacier

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I’m right up next to a limit on live (easily-accessible, always visible in photo apps) cloud storage, with years of family photos and video taking about 95% of that.

I definitely don’t want to delete any of it, so I have been just hoping for bigger storage to be offered soon, but…

I hadn’t considered that re-encoding could be an option. I take standalone snapshots of everything every few months so if re-encoding would make a significant difference I might have to try this.

Do you have any tips on tools, parameters etc. that work well for you, please?

I use a shell script with ffmpeg. I encourage you to check out what works best for you but honestly the quality is pretty stellar with just a really simple one like

    mkdir -p reencoded

    ffmpeg -i input_filename.mp4 -c:v libx265 -crf 26 -preset fast -c:a aac -b:a 128k reencoded/output_filename.mp4

That's a fast single-pass constant quality encode - a two-pass encode would be better quality for the size but I find that very acceptable. It knocks down what would be a ~2gb file all the way to between 800mb - 1200mb with very reasonable quality, sometimes even more - I've seen a 5gb file become a 400mb file (!!). You can experiment with the -crf 26 parameter to get the quality/size tradeoff you like. I run that over every video in the directory as a cron job basically.

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