二值图像的blob检测图像处理

Question

我的blob探测器没有给我的二值图像着色。有人能解释这个问题吗？

代码：

## mask of yellow color
mask_yellow = cv2.inRange(Img, (0, 180, 240), (20, 255, 255))

#define kernel size
kernel = np.ones((15,15), np.uint8)
# Remove unnecessary noise from mask
mask_yellow = cv2.morphologyEx(mask_yellow, cv2.MORPH_CLOSE, kernel)
mask_yellow = cv2.morphologyEx(mask_yellow, cv2.MORPH_OPEN, kernel)

#scale window size
mask_yellow_view = cv2.resize(mask_yellow, dsize)

#show yellow colors
cv2.imshow('Yellow mask', mask_yellow_view)

mask_yellow = cv2.bitwise_not(mask_yellow)

mask_yellow = cv2.cvtColor(mask_yellow, cv2.COLOR_GRAY2RGB)

params = cv2.SimpleBlobDetector_Params()

params.filterByArea = True
params.minArea = 10000

detector = cv2.SimpleBlobDetector_create(params)
keypoints = detector.detect(mask_yellow)

blank = np.zeros((20, 20))
blobs = cv2.drawKeypoints(mask_yellow, keypoints, blank, (0, 0, 255),cv2.DRAW_MATCHES_FLAGS_DRAW_RICH_KEYPOINTS)


# Show keypoints
cv2.imshow("Keypoints", blobs)

Answer 1

对我来说你的代码很好。下面是我使用的简化代码和示例输入输出图像。在我的例子中，params.minArea阈值太高，所以我不得不降低它。请检查您的过滤标准是否符合您的输入！

import cv2

img = cv2.imread("img.png")

# mask of yellow color
mask_yellow = cv2.inRange(img, (0, 180, 240), (20, 255, 255))
mask_yellow = cv2.bitwise_not(mask_yellow)
mask_yellow = cv2.cvtColor(mask_yellow, cv2.COLOR_GRAY2RGB)

params = cv2.SimpleBlobDetector_Params()

params.filterByArea = True
params.minArea = 1000

detector = cv2.SimpleBlobDetector_create(params)
keypoints = detector.detect(mask_yellow)

blobs = cv2.drawKeypoints(mask_yellow, keypoints, 0, (0, 0, 255), cv2.DRAW_MATCHES_FLAGS_DRAW_RICH_KEYPOINTS)

cv2.imwrite("out.png", blobs)

输入图像：

​

​

输出图像：

​

​