I have been looking at harris feature detection lately. Implementing it side by side in OpenCV and SciPy, luckily for me a SciPy implementation by Jan Solem was found on this blog. As I was going through the code, I wanted to get my head around what was happening. So using these two lines:
from IPython.Shell import IPShellEmbedIPShellEmbed()()
This piece of magic can be put anywhere, right deep inside a nested loop, inside a function called from X via Y via Z etc. And it obviously pops you right into the brilliant IPython shell, with the full normal IPython luxuries like timeit, history, autocomplete, pylab plotting... So I plotted a few images midway through processing, just to see what the program sees.
First is the grayscale image taken from my webcam. No I'm not colour blind - I realize I have plotted it in colour.... Second and thirdly the two gaussian derivatives of the image, one in X and one in Y.
And a bit later after getting the thing going - the final output! Pretty cool to see how it came about with the two derivatives convolved together. Some filtering to choose spread out points (clearly not working) and then drawing dots! The code for this in OpenCV and in SciPy is here.
Oh and check it out - my first conference presentation!
Ahh, I'm going to have to prepare something now!