img2ascii.py

#-*- coding: utf-8 -*-
from PIL import Image


MAX_LEN = 100.0
FIX_RATE = 1.8
REPLACEMENT = 'MNHQ$OC?7>!:-;. '


def convert(filename):
    image = Image.open(filename)
    image = image.convert('L')

    width, height = image.size
    rate = MAX_LEN / width
    width = int(rate * width)
    height = int(rate * height / FIX_RATE)

    image = image.resize((width, height))

    data = image.load()

    output = ''

    for h in xrange(height):
        for w in xrange(width):
            output += REPLACEMENT[int(data[w, h] / 256.0 * 16)]
        output += '\n'

    print output


convert('demo.jpg')