How are quality presets and min/max settings related?

[mdelarioja]

It's unclear from the documentation how these options are related. If I choose the "high" quality preset, does that have any effect on the min/max compression options? E.g. if the high quality preset is used, does that mean that the min is set at 60 rather than the default (40)?

[Sindre Sorhus]

We would be happy to update the docs if anyone can figure it out. The docs here are just taken from the jpeg-recompress CLI:

❯ ./jpeg-recompress

  Usage: ./jpeg-recompress [options] input.jpg compressed-output.jpg

  Options:

    -V, --version                 output program version
    -h, --help                    output help information
    -t, --target [arg]            Set target quality [0.9999]
    -q, --quality [arg]           Set a quality preset: low, medium, high, veryhigh [medium]
    -n, --min [arg]               Minimum JPEG quality [40]
    -x, --max [arg]               Maximum JPEG quality [95]
    -l, --loops [arg]             Set the number of runs to attempt [6]
    -a, --accurate                Favor accuracy over speed
    -m, --method [arg]            Set comparison method to one of 'mpe', 'ssim', 'ms-ssim', 'smallfry' [ssim]
    -s, --strip                   Strip metadata
    -d, --defish [arg]            Set defish strength [0.0]
    -z, --zoom [arg]              Set defish zoom [1.0]
    -r, --ppm                     Parse input as PPM instead of JPEG
    -c, --no-copy                 Disable copying files that will not be compressed
    -p, --no-progressive          Disable progressive encoding
    -S, --subsample [arg]         Set subsampling method. Valid values: 'default', 'disable'. [default]
    -Q, --quiet                   Only print out errors.

https://github.com/danielgtaylor/jpeg-archive#jpeg-recompress