pix2text.py

#!/usr/bin/env python
import sys
from argparse import ArgumentParser
from PIL import Image
import svgwrite


def pix2char(image, x, y, palette):
    try:
        l, a = image.getpixel((x, y))
    except IndexError:
        return ""
    val = ((1 - l / 255.0) * a / 255.0)
    index = int(val * (len(palette) - 1))
    return palette[index]


parser = ArgumentParser(add_help=False)
parser.add_argument(
    "input"
)
parser.add_argument(
    "output"
)
parser.add_argument(
    "--palette", "-p",
    default=" .-:asdgMX#",
)
parser.add_argument(
    "--subchar", "-s",
    type=int,
    default=1,
)
parser.add_argument(
    "--width", "-w",
    type=int,
    default=None,
)
parser.add_argument(
    "--height", "-h",
    type=int,
    default=None,
)
parser.add_argument(
    "--font-size", "-f",
    type=int,
    default=12,
)

options = parser.parse_args()
image = Image.open(options.input).convert('LA')
subchar = options.subchar
text = [""] * (subchar ** 2)

if options.width or options.height:
    width = options.width or image.size[0] * options.height / image.size[1]
    height = options.height or image.size[1] * width / image.size[0]
    image.thumbnail((width, height))

for y in xrange(0, image.size[1], subchar):
    for x in xrange(0, image.size[0], subchar):
        for subchar_y in xrange(0, subchar):
            for subchar_x in xrange(0, subchar):
                index = subchar_x + subchar_y * subchar
                text[index] += pix2char(image, x+subchar_x, y+subchar_y, options.palette)

    for i in xrange(len(text)):
        text[i] += "\n"

font_size = options.font_size
svg = svgwrite.Drawing(options.output)
svg.add(svg.style("""
text {{
    letter-spacing: {letter_spacing}px;
    font-size: {font_size}px;
    font-family: monospace;
    fill: rgba(0, 0, 0, {alpha});
    font-weight: bold;
    white-space:pre;
}}""".format(
    font_size=font_size,
    letter_spacing=font_size,
    alpha=1.0 / (subchar ** 2),
)))

g = svg.g(transform="scale(1.25, 1)")
for subchar_y in xrange(0, subchar):
    for subchar_x in xrange(0, subchar):
        index = subchar_x + subchar_y * subchar
        g.add(svg.text(text[index], insert=(
            subchar_x * font_size / float(subchar),
            subchar_y * font_size / float(subchar),
        )))
svg.add(g)
svg.save()