matomo-icons/convert.sh

#!/bin/bash
shopt -s globstar
size=16

for i in src/**/*.{png,gif,jpg,ico}; do
    echo "$i"
    absDirname=$(dirname "$i")
    origFilename=$(basename "$i")
    code=${origFilename%.*}
    dirname="dist/${absDirname#src/}"
    distFile="${dirname}/${code}.png"
    echo "$distFile"
    if [ ! -d "$dirname" ]
    then
        mkdir -p "$dirname"
    fi
    if [[ $i == *.ico ]]
    then
        if file "$i" | grep -E "HTML|empty|ASCII text|: data|SVG" # if no valid image
        then
            rm "$i"
        else
            if [ ! -d "tmp" ]
            then
                mkdir "tmp"
            fi
            largestIcon=$(python analyseIco.py "$i")
            newIcon="tmp/${code}.ico"
            convert ${i}\[$largestIcon\] $newIcon
            i=$newIcon
        fi
    fi
    # if file (or symlink) -> didn't get deleted
    if [ -e "$i" ]
    then
        convert \
            "$i" \
            -strip \
            -transparent white \
            -background none \
            -trim \
            -resize ${size}x${size} \
            -gravity center \
            -extent ${size}x${size} \
            "$distFile"
            # input file
            # strip metadata
            # make background transparent
            # keep transparency
            # cut border
            # get only one image from .ico
            # resize while keeping the aspect ratio
            # center image
            # fit to 16x16
        # optimize png:
        pngquant -f --ext .png -s 1 --skip-if-larger --quality 70-95 "$distFile"
    fi
done