from PIL import Image

#要处理的图片名
IMG = 'aa.jpg'
#宽像素点
WIDTH = 500
#高像素点
HEIGHT = 700
#输出路径
OUTPUT = None

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__':

    #打开图片并重置大小
    im = Image.open(IMG)
    im = im.resize((WIDTH, HEIGHT), Image.NEAREST)
    #显示图片
    im.show()

    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)