python - 如何在Python中用虚线标记给定区域制作分割掩码

Question

我想通过编码为一些图像制作分割蒙版。有一个工具可以生成带有边界点近似坐标的xml文件。这些坐标可以通过获取标签值来获得。图像尺寸为 800x600 像素。

例如，从此工具中提取了以下几点。如何填充标有虚线的轮廓内的区域，例如白色？谢谢。

点 = [(737, 255), (736, 265), (735, 270), (739, 273), (746, 264), (755, 268), (765, 272), (767, 276), (769, 278), (776, 275), (776, 264), (767, 260), (753, 257), (738, 256), (738, 256), (479, 247), (455, 244), (446, 245), (440, 243), (430, 244), (423, 241), (419, 238), (412, 232), (406, 225), (403, 202), (404, 185), (410, 170), (414, 166), (424, 160), (439, 157), (456, 166), (469, 177), (472, 197), (480, 199), (492, 214), (494, 207), (488, 201), (492, 193), (497, 194), (502, 196), (510, 196), (518, 197), (523, 202), (521, 209)]

import Image
import numpy as np

a = Image.new('RGB',(800,600),0)
for p in points:
  a.putpixel(p,(255,255,255))
a.show()
a.save('./Original_mask.png')

原始掩码:

预期掩码:

Answer 1

基本上来说，如果你想填充散点限制的区域，可以使用cv2.drawContours。

import cv2
import numpy as np

points = [
    (737, 255), (736, 265), (735, 270), (739, 273), (746, 264),
    (755, 268), (765, 272), (767, 276), (769, 278), (776, 275), (776, 264),
    (767, 260), (753, 257), (738, 256), (738, 256), (479, 247), (455, 244),
    (446, 245), (440, 243), (430, 244), (423, 241), (419, 238), (412, 232),
    (406, 225), (403, 202), (404, 185), (410, 170), (414, 166), (424, 160),
    (439, 157), (456, 166), (469, 177), (472, 197), (480, 199), (492, 214),
    (494, 207), (488, 201), (492, 193), (497, 194), (502, 196), (510, 196),
    (518, 197), (523, 202), (521, 209)
    ]

canvas = np.zeros((600, 800,3), np.uint8)
pts = np.array([[x,y] for(x,y) in points])
cv2.drawContours(canvas, [pts],-1, (0,255,0), -1)
cv2.polylines(canvas, [pts], isClosed=True, color=(255,0,0), thickness=2)
cv2.imshow("canvas", canvas);cv2.waitKey();cv2.destroyAllWindows()

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我认为这些点的顺序可能是错误的。