Converts images to mobile resolutions.

convert_mobile.py

#!/bin/usr/python

# This script converts images to lower resolutions for android and ios.
# It assumes the image is in 4x/xxxhdpi
# Requires imagemagick.

import subprocess
import sys
import os

iosFolder = "ios"
androidFolder = "android"

androidFrac = {
    "drawable-xxhdpi": '75',    # 3/4
    "drawable-xhdpi": '50',     # 2/4
    "drawable-hdpi": '37.5',    # 1.5/4
    "drawable-mdpi": '25'       # 1/4
}

iosFrac = {
    '@3x': '75',    # 3/4
    '@2x': '50',    # 2/4
    '@1x': '25'     # 1/4
}

def convert_file(fname):

    for size, frac in iosFrac.iteritems():
        f, ext = os.path.splitext(fname)

        # create dirs
        if not os.path.exists(iosFolder):
            os.makedirs(iosFolder)

        # convert <f>.<ext> -resize <frac>% <iosFolder>/<f>-<size>.<ext>
        subprocess.call([
            "convert",
            fname,
            "-resize",
            frac + "%",
            os.path.join(iosFolder, f + "-" + size + ext)
        ])

    for size, frac in androidFrac.iteritems():
        f, ext = os.path.splitext(fname)

        # create dirs
        dpath = os.path.join(androidFolder, size)
        if not os.path.exists(dpath):
            os.makedirs(dpath)

        # convert <f>.<ext> -resize <frac>% <androidFolder>/<size>/<f>.<ext>
        subprocess.call([
            "convert",
            fname,
            "-resize",
            frac + "%",
            os.path.join(dpath, fname)
        ])
    
    print "Processed '%s'" % fname
    
    return

if __name__ == '__main__':
    for f in sys.argv[1:]:
        convert_file(f)
    print "Done"