img_to_box_drawing.py

#!/usr/bin/env python3.6

BOX_CHARS = list(' ▘▝▀▖▌▞▛▗▚▐▜▄▙▟█')
BOX_PIXEL_ORDER = ((0,0), (1,0), (0,1), (1,1))

from argparse import ArgumentParser
from PIL import Image
from subprocess import Popen, PIPE

parser = ArgumentParser('Image to block character converter')
parser.add_argument('filename', help='File to convert to text')
args = parser.parse_args()

im = Image.open(args.filename)

out, errs = Popen(['tput', 'cols'], stdout=PIPE).communicate()
text_cols = int(out)
out, errs = Popen(['tput', 'lines'], stdout=PIPE).communicate()
text_rows = int(out)

img_width = text_cols * 2
img_height = text_rows * 2

factor = min([img_width / im.width / 2, img_height / im.height])
thumb = im.resize((int(im.width * factor * 2), int(im.height * factor)))

thumb_px = thumb.load()

class PixelGetter:
  def __init__(self, pixelAccess):
    self._pixelAccess = pixelAccess
  def __getitem__(self, xy):
    try:
      r,g,b,*rest = self._pixelAccess[xy]
      if (r + g + b) / 3 > 127:
        return 1
      else:
        return 0
    except IndexError:
      return 0

def binaryOr(itr):
  ret = 0
  for i in itr:
    ret |= i
  return ret



getter = PixelGetter(thumb_px)

print('\n'.join(
  ''.join(
    BOX_CHARS[binaryOr(
      getter[(x+x1, y+y1)] << i
      for i, (x1, y1) in enumerate(BOX_PIXEL_ORDER)
    )]
    for x in range(0, thumb.width, 2)
  )
  for y in range(0, thumb.height, 2)
))