计算两条平行白色直线间黑色像素个数的python代码及测试图片

from PIL import Image

def count_black_pixels(filename):
    # 打开图片
    img = Image.open(filename)
    # 转换为灰度图
    img_gray = img.convert('L')
    # 获取像素矩阵
    pixels = img_gray.load()
    # 获取图片宽度和高度
    width, height = img.size
    # 计算黑色像素数
    black_pixels = 0
    for y in range(height):
        for x in range(width):
            if pixels[x, y] < 128:  
                black_pixels += 1
    return black_pixels

if __name__ == '__main__':
    filename = 'test.jpg'  # 测试图片的文件名
    left_line = (20, 0)  # 平行线的左边线的起点坐标
    right_line = (200, 0)  # 平行线的右边线的起点坐标
    height = 300  # 平行线的高度
    # 在图片上画出平行线
    img = Image.open(filename)
    draw = ImageDraw.Draw(img)
    draw.line((left_line, (left_line[0], left_line[1] + height)), fill='white', width=2)
    draw.line((right_line, (right_line[0], right_line[1] + height)), fill='white', width=2)
    img.show()
    # 计算两条平行线之间的黑色像素数
    black_pixels = count_black_pixels(filename)
    print('两条平行线之间的黑色像素数:', black_pixels)

测试图片：