convert_image.py

#!/usr/bin/python

import sys
import argparse
try:
	# windows
	from PIL import Image
except ImportError:
	# osx
	import Image

HEIGHT = 90
def process_pixel(r,g,b, a=255):
	# invert white to black
	# if a < 150 or (r > 240 and g > 240 and b > 240):
		# return 0,0,0

	return b/4,g/4,r/4



def main():
	parser = argparse.ArgumentParser()
	parser.add_argument("image_file", help="Path to an image (gif, jpg, png, etc)")
	parser.add_argument("-r", "--rescale", help="rescale the image proportionaly so that it's 72 pixels high", action="store_true")
	args = parser.parse_args()

	filename = args.image_file
	#rows = 9 # rows = sys.argv[2]

	im = Image.open(filename).convert("RGB")
	if args.rescale and im.size[1] != HEIGHT:
		ratio = float(HEIGHT)/im.size[1]
		im = im.resize((int(round(im.size[0]*ratio)), HEIGHT), Image.ANTIALIAS)
	elif im.size[1] > HEIGHT:
		delta = im.size[1] - HEIGHT
		im = im.crop((0,delta/2, im.size[0], im.size[1] - delta/2))

	cols, rows = im.size
	assert rows == HEIGHT

	data = []
	for column in xrange(cols):
		col_data = []
		for row in xrange(rows):
			pixel = im.getpixel((column, row));
			#r,g,b = process_pixel(*pixel)
			col_data.extend(process_pixel(*pixel))
			#val_to_write = b  | (g << 8) | (r << 16)
			#col_data.append(val_to_write)
		data.append(col_data)

	#data_string = ",\n".join(', '.join(["{2},{1},{0}".format(pixel & 255, (pixel >> 8) & 255, (pixel >> 16) & 255) for pixel in column]) for column in data)
	data_string = ",\n".join(','.join("{: 3}".format(i) for i in column[::-1]) for column in data)

	print "#define IMAGE_COLUMNS {}".format(cols);
	print "#define IMAGE_ROWS {}".format(rows);
	print "// pixel size in bytes"
	print "#define PIXEL_SIZE 3"
	#print "const uint32_t picture[] PROGMEM = {{\n{data}\n}};".format(data=data_string)
	print "const uint8_t picture[] PROGMEM = {{\n{data}\n}};".format(data=data_string)


if __name__=='__main__':
	main()