iOS 8 Icons

resizer.py

import os
import sys
import numpy
from PIL import Image

if len(sys.argv) < 3:
    print('You must specifiy an image and an output folder')
    print('i.e. "resizer.py image.png output_folder_name')
    sys.exit(1)

# iOS 8 iPhone icon sizes
iphone = {
		58: 'icon_iphone_small@2x.png',
		87: 'icon_iphone_small@3x.png',
		80: 'icon_iphone_spotlight@2x.png',
		120: 'icon_iphone_spotlight@3x.png',
		120: 'icon_iphone@2x.png',
		180: 'icon_iphone@3x.png'
		}

# iOS 8 iPad icon sizes
ipad = {
		29: 'icon_ipad_small.png',
		58: 'icon_ipad_small@2x.png',
		40: 'icon_ipad_spotlight.png',
		80: 'icon_ipad_spotlight@2x.png',
		76: 'icon_ipad.png',
		152: 'icon_ipad@2x.png'
		}

imageFile = sys.argv[1]
outputFolder = sys.argv[2]

# Define our resizing method
def resizeImage(image, size, output):
	img = Image.open(image)
	premult = numpy.fromstring(img.tostring(), dtype=numpy.uint8)
	alphaLayer = premult[3::4] / 255.0
	premult[::4] *= alphaLayer
	premult[1::4] *= alphaLayer
	premult[2::4] *= alphaLayer
	img = Image.fromstring("RGBA", img.size, premult.tostring())
	img.resize((size, size), Image.ANTIALIAS).save(output)

# Check and see if the folder already exists
if not os.path.isdir(outputFolder):
	os.mkdir(outputFolder)

# Change our current working directory to our output folder
os.chdir(outputFolder)



print('### Converting iPhone Icons ###')
for size in iphone.keys():
	print('   Creating %s icon' % iphone[size])
	resizeImage(imageFile, size, iphone[size])

print('### Finished Creating iPhone Icons ###')
print('')

print('### Converting iPad Icons ###')
for size in ipad.keys():
	print('   Creating %s icon' % ipad[size])
	resizeImage(imageFile, size, ipad[size])

print('### Finished Creating iPhone Icons ###')