python - 手势检测

Question

当我运行这个:

contours,_,hierarchy = cv2.findContours(thresh.copy(),cv2.RETR_TREE, cv2.CHAIN_APPROX_NONE)

我收到此错误:

ValueError: not enough values to unpack (expected 3, got 2)

我也尝试过:

_, contours,hierarchy = cv2.findContours(thresh.copy(),cv2.RETR_TREE, cv2.CHAIN_APPROX_NONE)

和:

contours,hierarchy,_ = cv2.findContours(thresh.copy(),cv2.RETR_TREE, cv2.CHAIN_APPROX_NONE)

并得到此错误:

Traceback (most recent call last):
  File "C:/Users/HASHMATI/AppData/Local/Programs/Python/Python37-32/new2hand.py", line 152, in <module>
    gestureRecognition(frame,roi_rect,frame[y:y+h, x:x+w])
  File "C:/Users/HASHMATI/AppData/Local/Programs/Python/Python37-32/new2hand.py", line 99, in gestureRecognition
    detectGesture(src,roi_rect,img_dilated)
  File "C:/Users/HASHMATI/AppData/Local/Programs/Python/Python37-32/new2hand.py", line 21, in detectGesture
    contours,_,hierarchy = cv2.findContours(thresh.copy(),cv2.RETR_TREE, cv2.CHAIN_APPROX_NONE)
ValueError: not enough values to unpack (expected 3, got 2)

Answer 1

这是OpenCV 3.x和4.x之间的区别。在3.x中，有三个返回值，在4.x中，只有两个。正如其他人提到的那样，您仅捕获contours和hierarchy:

contours, hierarchy = cv2.findContours(thresh.copy(),cv2.RETR_TREE, cv2.CHAIN_APPROX_NONE)

另外，如果您真正想要的是使用3.x，则可以降级您的OpenCV版本。