trouble in finding pixel by pixel difference of two images [closed] - python

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rows, cols = img1.shape[:2]
x = np.random.randint(0, 255, (w1, h1))
for i in range(rows):
for j in range(cols):
k = x[i, j]
I am finding difficulty in completing the code for finding the pixel by pixel difference of two images in Python OpenCV. Could you please help me with the right code.

In any case you should avoid loops over single pixels, but use operations which work on full images
You may want to have a look at the general OpenCV Python tutorial.
There is a chapter on arithmetic operation on images, this is what you are looking for:
http://docs.opencv.org/3.1.0/d0/d86/tutorial_py_image_arithmetics.html#gsc.tab=0
The pdf version of the complete tutorial can be found here:
https://media.readthedocs.org/pdf/opencv-python-tutroals/latest/opencv-python-tutroals.pdf

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I would like to code a program that will use a phones camera to read a node graph and then perform dijkstra's algorithm on it, displaying the shortest path.
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Cheers,
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Did you try this?
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