I’m trying to extract the frames of a video as individual images but it’s really slow, except when I’m using jpeg. The obvious issue with jpegs is the data loss from the compression, I want the images to be lossless. Extracting them as jpegs manages about 50-70 fps but as pngs it’s only 4 fps and it seems to continue getting slower, after 1 minute of the 11 minute video it’s only 3.5 fps.

I suspect it’s because I’m doing this on an external 5tb hard drive, connected over USB 3.0 and the write speed can’t keep up. So my idea was to use a different image format. I tried lossless jpeg xl and lossless webp but both of them are even slower, only managing to extract at about 0.5 fps or something. I have no idea why that’s so slow, the files are a lot smaller than png, so it can’t be because of the write speed.

I would appreciate it if anyone could help me with this.

    • cmnybo@discuss.tchncs.de
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      4 months ago

      Well, you found your problem then. You will need to get a decent quality SSD to speed it up. Avoid those cheap QLC SSDs, they are slower than mechanical hard drives once the SLC cache fills up.

      • Fisch@discuss.tchncs.deOP
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        4 months ago

        I don’t really wanna buy another SSD just for this. I already have two SSDs in my PC, I just don’t have enough storage left. All the frames are gonna be like 300gb.