cv2.threshold() 中的哪些设置会影响此图像？

Question

我想在 OpenCV 中将此图像转换为灰度，然后找到对其设置阈值的设置。我想对头骨内部的黑色空间设置阈值。有人可以使用 OpenCV 写出 Python 脚本吗？

我转换为灰度：gray = cv2.cvtColor(pic, cv2.COLOR_BGR2GRAY)

当我这样做时 (ret, thresh) = cv2.threshold(gray, 177, 255, cv2.THRESH_BINARY) 我得到一张黑色图像。

当我这样做时 (ret, thresh) = cv2.threshold(gray, 0, 255, cv2.THRESH_BINARY) 整个头变成了白色斑点。

Answer 1

如果我没有正确理解您的目标，这是我的建议。正如@stateMachine 所说，它使用 Otsu 的阈值。

import cv2

im = cv2.imread("IScDg.png")
gray = cv2.cvtColor(im, cv2.COLOR_BGR2GRAY)

# Your first method
(_, thresh1) = cv2.threshold(gray, 177, 255, cv2.THRESH_BINARY)

# Your second method
(ret, thresh2) = cv2.threshold(gray, 0, 255, cv2.THRESH_BINARY)

# Proposed method
(_, thresh3) = cv2.threshold(gray, 0, 1, cv2.THRESH_BINARY | cv2.THRESH_OTSU)

different thresholds on your image

Answer 2

我经常涂OTSU，效果很好。

ret,gray = cv2.threshold(gray,100,255,cv2.THRESH_BINARY+cv2.THRESH_OTSU)

cv2.threshold() 中的哪些设置会影响此图像？

What settings in cv2.threshold() to threshold this image?

python

opencv

image-thresholding