Python图片转字符画

安装PIL(pillow)库：
$ sudo apt-get update
$ sudo apt-get install python-dev
$ sudo apt-get install libtiff5-dev libjpeg8-dev zlib1g-dev libfreetype6-dev liblcms2-dev libwebp-dev tcl8.6-dev tk8.6-dev python-tk
$ sudo pip install pillow

源码：
from PIL import Image
import argparse

命令行输入参数处理

parser = argparse.ArgumentParser()

parser.add_argument('file') #输入文件
parser.add_argument('-o', '--output') #输出文件
parser.add_argument('--width', type = int, default = 80) #输出字符画宽
parser.add_argument('--height', type = int, default = 80) #输出字符画高

获取参数

args = parser.parse_args()

IMG = args.file
WIDTH = args.width
HEIGHT = args.height
OUTPUT = args.output

ascii_char = list("$@B%8&WM#*oahkbdpqwmZO0QLCJUYXzcvunxrjft/|()1{}[]?-_+~<>i!lI;:,"^`'. ")

将256灰度映射到70个字符上

def get_char(r,g,b,alpha = 256):
if alpha == 0:
return ' '
length = len(ascii_char)
gray = int(0.2126 * r + 0.7152 * g + 0.0722 * b)

unit = (256.0 + 1)/length
return ascii_char[int(gray/unit)]

if name == 'main':

im = Image.open(IMG)
im = im.resize((WIDTH,HEIGHT), Image.NEAREST)

txt = ""

for i in range(HEIGHT):
    for j in range(WIDTH):
        txt += get_char(*im.getpixel((j,i)))
    txt += '\n'

print txt

#字符画输出到文件
if OUTPUT:
    with open(OUTPUT,'w') as f:
        f.write(txt)
else:
    with open("output.txt",'w') as f:
        f.write(txt)