python - 测量透明图像与实际图像的距离

Question

我正在尝试测量透明边界到图像的距离(在 y 轴上):

from PIL import Image
im = Image.open('test.png')
im.show()
#im.size = (500,500) I assume the distance will be from 200-300

是否有办法做到这一点或获得从钱包顶部到透明图像顶部的估计？

Answer 1

您可以使用 numpy 来操作图像:

import numpy as np
from PIL import Image
im = Image.open('test.png')

#split image
r, g, b, a = np.array(img)[:,:,0], np.array(img)[:,:,1], np.array(img)[:,:,2], np.array(img)[:,:,3]
idx, idy = np.where(a>0)

# distance to borders (left, right, top, bottom)
distx = (idx.min(), a.shape[0] - idx.max())
disty = (idy.min(), a.shape[1] - idy.max())