mario jack's profile - activity

I'm just working with code from the python tutorials.

In certain cases the imwrite('messigray.png',img) returns "FALSE" value. In this case no Image is stored.

What is the reason for this?

• I've installed today opencv 2.4.10

• I'm using some standard code from the tutorial:

  import numpy as np import sys sys.path.append('/usr/local/lib/python2.7/site-packages')

  import cv2
  
  cap = cv2.VideoCapture(0)
  
      # Capture frame-by-frame
  ret, frame = cap.read()
  
      # Our operations on the frame come here
  gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)
  
      # Display the resulting frame
  cv2.imshow('frame',gray)
  
  #cv2.imwrite("I2.jpg",img)
  
  # When everything done, release the capture
  cap.release()
  cv2.destroyAllWindows()
  

*

• I'm getting the following error messages:

  OpenCV Error: Assertion failed (scn == 3 || scn == 4) in cvtColor, file /home/pi/opencv-2.4.10/modules/imgproc/src/color.cpp, line 3739 Traceback (most recent call last): File "I2_video.py", line 14, in <module> gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY) cv2.error: /home/pi/opencv-2.4.10/modules/imgproc/src/color.cpp:3739: error: (-215) scn == 3 || scn == 4 in function cvtColor