pixel_count.py

## pixel_count.py
from operator import itemgetter
from PIL import Image, ImageDraw, ImageFont


# Make a lowercase + uppercase alphabet.
alphabet = 'abcdefghijklmnopqrstuvwxyz'
alphabet += ''.join(map(str.upper, alphabet))


# We'll use Helvetica in big type.
helvetica = ImageFont.truetype('Helvetica.ttf', 100)


def draw_letter(letter, save=True):
    img = Image.new('RGB', (100, 100), 'white')

    draw = ImageDraw.Draw(img)
    draw.text((0,0), letter, font=helvetica, fill='#000000')

    if save:
        img.save("imgs/{}.png".format(letter), 'PNG')

    return img


def count_black_pixels(img):
    pixels = list(img.getdata())
    return len(filter(lambda rgb: sum(rgb) == 0, pixels))


if __name__ == '__main__':
    counts = [
        (letter, count_black_pixels(draw_letter(letter)))
        for letter in alphabet
    ]

    print sorted(counts, key=itemgetter(1), reverse=True)

## pixel_count_many_fonts.py
# -*- coding: utf-8 -*-
from __future__ import division
import os
from collections import defaultdict
from math import sqrt
from PIL import Image, ImageDraw, ImageFont


# Make a lowercase + uppercase alphabet.
alphabet = 'abcdefghijklmnopqrstuvwxyz'
alphabet += ''.join(map(str.upper, alphabet))


def draw_letter(letter, font, save=True):
    img = Image.new('RGB', (100, 100), 'white')

    draw = ImageDraw.Draw(img)
    draw.text((0,0), letter, font=font, fill='#000000')

    if save:
        img.save("imgs/{}.png".format(letter), 'PNG')

    return img


def count_black_pixels(img):
    pixels = list(img.getdata())
    return len(filter(lambda rgb: sum(rgb) == 0, pixels))


def available_fonts():
    for root, dirs, filenames in os.walk('/Users/alex/Desktop/English'):
        for name in filenames:
            path = os.path.join(root, name)
            try:
                yield ImageFont.truetype(path, 100)
            except IOError:
                pass


def letter_statistics(counts):
    for letter, counts in sorted(counts.iteritems()):
        n = len(counts)
        mean = sum(counts) / n
        sd = sqrt(sum((x - mean) ** 2 for x in counts) / n)
        yield letter, mean, sd


def main():
    counts = defaultdict(list)

    for letter in alphabet:
        for font in available_fonts():
            img = draw_letter(letter, font, save=False)
            count = count_black_pixels(img)
            counts[letter].append(count)

    for letter, mean, sd in letter_statistics(counts):
        print u"{0}: {1:.2f} ± {2:.2f}".format(letter, mean, sd)


if __name__ == '__main__':
    main()

## results_helvetica
[('M', 2493), ('W', 2414), ('B', 1909), ('R', 1857), ('G', 1798), ('N', 1779), ('D', 1765), ('Q', 1758), ('g', 1657), ('O', 1652), ('E', 1635), ('S', 1610), ('m', 1545), ('A', 1539), ('K', 1539), ('H', 1528), ('U', 1528), ('w', 1513), ('b', 1452), ('Z', 1445), ('C', 1429), ('X', 1420), ('P', 1419), ('p', 1388), ('q', 1388), ('d', 1381), ('V', 1207), ('e', 1202), ('F', 1195), ('a', 1171), ('k', 1157), ('h', 1145), ('T', 1056), ('y', 1053), ('L', 1045), ('z', 1044), ('Y', 1031), ('o', 1016), ('n', 1012), ('u', 985), ('s', 976), ('c', 883), ('J', 874), ('x', 816), ('v', 761), ('t', 739), ('f', 722), ('j', 701), ('l', 584), ('I', 584), ('r', 570), ('i', 512)]

## results_many
A: 1443.91 ± 644.15
B: 1841.38 ± 685.26
C: 1247.28 ± 543.88
D: 1741.80 ± 675.39
E: 1562.66 ± 592.35
F: 1287.51 ± 485.45
G: 1598.12 ± 660.65
H: 1829.83 ± 738.88
I: 912.00 ± 402.38
J: 1020.24 ± 419.26
K: 1648.93 ± 687.54
L: 1078.63 ± 428.35
M: 2217.51 ± 945.19
N: 1810.05 ± 758.11
O: 1647.88 ± 684.50
P: 1450.26 ± 555.61
Q: 1921.22 ± 792.46
R: 1770.32 ± 672.66
S: 1358.10 ± 591.48
T: 1183.93 ± 481.17
U: 1500.25 ± 640.91
V: 1281.79 ± 580.83
W: 2139.06 ± 945.29
X: 1448.34 ± 638.57
Y: 1162.64 ± 489.21
Z: 1452.01 ± 591.28
a: 1126.90 ± 466.50
b: 1416.52 ± 587.70
c: 817.44 ± 368.99
d: 1435.09 ± 594.68
e: 1057.23 ± 458.34
f: 1017.09 ± 449.75
g: 1522.26 ± 636.10
h: 1374.94 ± 582.75
i: 686.07 ± 327.42
j: 888.88 ± 412.74
k: 1318.74 ± 575.17
l: 797.02 ± 327.72
m: 1725.93 ± 746.73
n: 1154.92 ± 494.20
o: 1065.75 ± 466.91
p: 1436.74 ± 601.54
q: 1419.39 ± 580.56
r: 729.67 ± 327.41
s: 903.54 ± 415.78
t: 849.93 ± 367.05
u: 1133.91 ± 485.74
v: 848.74 ± 411.86
w: 1433.83 ± 671.25
x: 960.69 ± 449.55
y: 1088.74 ± 509.81
z: 969.60 ± 414.24