Python图片转字符画

Posted 2020-07-28

目的：将一张图片转换成字符画，采用灰度值与字符对应的算法实现像素与字符之间的转化，另外通过

argparse实现命令行参数管理，argparse其作用是为文件添加命令行参数并获取，用于程序运行输入

关键算法：

# 将256灰度映射到70个字符上
def get_char(r, b, g, alpha=256):
if alpha == 0:
return ‘ ‘
length = len(ascii_char)
gray = int(0.2126 * r + 0.7152 * g + 0.0722 * b) #灰度值计算公式
unit = (256.0 + 1) / length
return ascii_char[int(gray / unit)]

完整代碼：

# -*- coding: utf-8 -*-

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("[email protected]%8&WM#*oahkbdpqwmZO0QLCJUYXzcvunxrjft/\|()1{}[]?-_+~<>i!lI;:,\"^`‘. ")

# 将256灰度映射到70个字符上
def get_char(r,b,g,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)