1. Calculate the absolute difference frame between two frames as the camera is capturing frames and threshold them with a specific value e.g. 20. Save the output abs. diff. frame in a video file.
2. Try for example to move your hands in front of the camera while capturing and analyzing the frames. You should be able to visually identify well the contour of your hands when these are moving but not so much when they are staying still.
3. This part continues from our previous demo with capturing frames from the camera using
4. load_camera.py
5.  
6. The load_camera.py:
7.  
8. # Load opencv module
9. import cv2
10. 
    
     
11. # Creat a VideoCapture object
12. cap = cv2.VideoCapture(0)
13. 
     
14. # Check if camera opened successfully
15. if (cap.isOpened() is False):
16. print("Unable to read camera feed")
17. 
     
18. # Default resolutions of the frame are obtained.
19. # The default resolutions
20. # are system dependent.
21. # We convert the resolutions from float to integer.
22. frame_width = int(cap.get(3))
23. frame_height = int(cap.get(4))
24. 
     
25. # Define the codec and create VideoWriter object. The output is
26. # stored in 'output.avi' file.
27. out = cv2.VideoWriter('output.avi',
28. cv2.VideoWriter_fourcc('M', 'J', 'P', 'G'),
29. 10, (frame_width,frame_height))
30. 
     
31. while(True):
32. ret, frame = cap.read()
33. 
     
34. if ret:
35. 
     
36. # color to grayscale
37. # Write the frame into the file 'output.avi'
38. out.write(frame)
39. print(frame.dtype)
40. print(frame.shape)
41. 
     
42. # Display the resulting frame
43. cv2.imshow('frame', frame)
44. 
     
45. # Press Q on keyboard to stop recording
46. if cv2.waitKey(1) & 0xFF == ord('q'):
47. break
48. 
     
49. # Break the loop
50. else:
51. break
52. 
     
53. # When everything done,
54. # release the video capture and write objects
55. cap.release()
56. out.release()
57. 
     
58. # Closes all the frames
59. cv2.destroyAllWindows()