Does the canny method apply Gaussian Blur?

edit

I was just wondering whether the canny() method in openCV applies a gaussian blur or not (I want to know whether I should use a gaussian blur before applying canny). Also, if it does, what parameter does it use by default for the blur?

It doesn't mention blur in the docs. However, the canny example here applies blur before applying canny(). So, I'm guessing the answer is no. I just wanted to make sure.

I went through the source code for canny(), but it doesn't explicitly call gaussian blur. I was thinking maybe it manually applies it (but I can't really read the source and understand it)...

I'm using openCV 2.4.5 btw