-*- import cv2

cv2 import numpy as np

np def sift_detector(new_image, template):

template):
image1=cv2.cvtColor(new_image,cv2.COLOR_BGR2GRAY)
 image2=template
 sift=cv2.SIFT()
 keypoints1, descriptors1=sift.detectAndCompute(image1,None)
 keypoints2, descriptors2=sift.detectAndCompute(image2,None)
 FLANN_INDEX_KDTREE=0
 index_param=dict(algorithm=FLANN_INDEX_KDTREE,trees=3)
 search_params=dict(checks=100)
 flann=cv2.FlannBasedMatcher(index_params,search_params)
 matches=flann.knnMatch(descriptors1,descriptors2,k=2)
 good_matches=[]
 for m,n in matches:
  if m.distance < 0.7 * n.distance:
 good_matches.append(m)
  return len(good_matches)

cap =cv2.VideoCapture(0)

template=cv2.imread("ben.jpg",0)

=cv2.VideoCapture(0) template=cv2.imread("ben.jpg",0) while True:

True:
ret,frame=cap.read()
 height, width= frame.shape[:2]
 top_left_x=width/3
 top_left_y=(height/2) + (height/4)
 bottom_right_x= (width/3)*2
 bottom_right_y= (height/2) - (height/4)
 cv2.rectangle(frame, (top_left_x,top_left_y), (bottom_right_x,bottom_right_y),(255,0,0),3)
 cropped=frame[bottom_right_y:top_left_y,bottom_right_x: top_left_x]
 frame=cv2.flip(frame,1)
 matches=sift_detector(cropped,template)
 cv2.putText(frame,str(matches),(450,450),cv2.FONT_HERSHEY_COMPLEX,2,(0,255,0),3)
 threshold=15
 if matches > threshold:
 cv2.rectangle(frame, (top_left_x,top_left_y), (bottom_right_x,bottom_right_y),(255,125,0),3)
  cv2.putText(frame,"object found", (50,50), cv2.FONT_HERSHEY_COMPLEX,2,(255,255,0),2)
 cv2.imshow("after process",frame)
 if cv2.waitKey(1)==13:
 break

cap.release()
cv2.destroyAllWindows()

And the error is

Traceback (most recent call last):
  File "C:\Users\Ahmet\Desktop\artificial intelligence\opencv çalışmaları\mini project 5.py", line 41, in <module>
 
<module>

    matches=sift_detector(cropped,template)
 
 File "C:\Users\Ahmet\Desktop\artificial intelligence\opencv çalışmaları\mini project 5.py", line 10, in sift_detector
 
sift_detector

keypoints1, descriptors1=sift.detectAndCompute(image1,None)
 
 error: C:\build\2_4_winpack-bindings-win64-vc14-static\opencv\modules\nonfree\src\sift.cpp:724: error: (-5) image is empty or has incorrect depth (!=CV_8U) in function cv::SIFT::operator ()()