我有下面的视网膜图像,我想在视盘(视网膜图像中的白色圆形)周围画一个圆。这是原始图像。
我使用了自适应阈值,然后使用了cv2. findcontour:
import cv2
def detectBlob(file):
# read image
img = cv2.imread(file)
imageName = file.split('.')[0]
# convert img to grayscale
gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
# do adaptive threshold on gray image
thresh = cv2.adaptiveThreshold(gray, 255, cv2.ADAPTIVE_THRESH_MEAN_C, cv2.THRESH_BINARY, 101, 3)
# apply morphology open then close
kernel = cv2.getStructuringElement(cv2.MORPH_ELLIPSE, (3,3))
blob = cv2.morphologyEx(thresh, cv2.MORPH_OPEN, kernel)
kernel = cv2.getStructuringElement(cv2.MORPH_ELLIPSE, (20,20))
blob = cv2.morphologyEx(blob, cv2.MORPH_CLOSE, kernel)
# invert blob
blob = (255 - blob)
# Get contours
cnts,hierarchy = cv2.findContours(blob, cv2.RETR_TREE, cv2.CHAIN_APPROX_SIMPLE)
# write results to disk
result = img.copy()
cv2.drawContours(result, cnts, -1, (0, 0, 255), 3)
cv2.imwrite(imageName+"_threshold.jpg", thresh)
cv2.imwrite(imageName+"_blob.jpg", blob)
cv2.imwrite(imageName+"_contour.jpg", result)
detectBlob('16.png')
这里是阈值的样子
这是最终输出的轮廓:
理想情况下,我希望有这样的输出。