"Improperly formatted code" when adding an additional image in an edit

Question

I made a question on Stack Overflow and then tried to edit it so that what I entered in the entry box was the exact text shown below in the code block.

The system would not let me post it, throwing an error about my post looking like it contained improperly formatted code. By editing it in pieces, I narrowed it down so by adding an empty line between [![Difference][2]][2] and [![Distribution][3]][3] at the bottom I was able to post. All the images were added using the "image" button in the toolbar.

I think this may be a bug, and I didn't want to end up posting a duplicate question so I did not try it again after I got it to work.

I downloaded a test image from Wikipedia (the tree seen below) to compare `Pillow` and `OpenCV` (using `cv2`) in Python. Perceptually the two images appear the same, but their respective `md5` hashes don't match; and if I subtract the two images the result is not even close to solid black (the image shown below the original). The original image is a JPEG. If I convert it to a PNG first, the hashes match.

The last image shows the frequency distribution of how the pixel value differences.

This is the code I used:

    from PIL import Image
    import cv2
    import sys
    import md5
    import numpy as np

    def hashIm(im):
        im = cv2.imread(im)
        imP = np.array(Image.open(im))

        # Convert to BGR and drop alpha channel if it exists
        imP = imP[..., 2::-1]
        # Make the array contiguous again
        imP = np.array(imP)

        cv2.imshow('cv2', im)
        cv2.imshow('PIL', imP)
        cv2.imshow('diff', (im-imP))

        with open('dist.csv', 'w') as outfile:
            diff = im-imP
            for i in range(1, 256):
                outfile.write('{},{}\n'.format(i, np.count_nonzero(diff==i)))

        cv2.waitKey(0)
        cv2.destroyAllWindows()

        return md5.md5(im).hexdigest() + '   ' + md5.md5(imP).hexdigest()

    if __name__ == '__main__':
        print sys.argv[1] + '\t' + hashIm(sys.argv[1])

[![Original (Wikipedia "Tree" article)][1]][1]
[![Difference][2]][2]
[![Distribution][3]][3]

  [1]: https://i.sstatic.net/iWUnD.jpg
  [2]: https://i.sstatic.net/UNNtB.png
  [3]: https://i.sstatic.net/Vk0Y8.png

Answer 1

Just put a horizontal ruler after the code:

    if __name__ == '__main__':
        print sys.argv[1] + '\t' + hashIm(sys.argv[1])

--------------------------------------------

[![Original (Wikipedia "Tree" article)][1]][1]
[![Difference][2]][2]
[![Distribution][3]][3]


  [1]: https://i.sstatic.net/iWUnD.jpg
  [2]: https://i.sstatic.net/UNNtB.png
  [3]: https://i.sstatic.net/Vk0Y8.png

The same applies for continuing after code with lists or citation blocks IIRC.

---

That should render well as intended:

I downloaded a test image from Wikipedia (the tree seen below) to compare Pillow and OpenCV (using cv2) in python. Perceptually the two images appear the same, but their respective md5 hashes don't match; and if I subtract the two images the result is not even close to solid black (the image shown below the original). The original image is a JPEG. If I convert it to a PNG first, the hashes match.

The last image shows the frequency distribution of how the pixel value differences.

This is the code I used:

   from PIL import Image
   import cv2
   import sys
   import md5
   import numpy as np

   # more code ...

---