Hello everyone,
While applying the stereo BM & SGBM algorithms implemented in OpenCV, I came across the notion of "Speckle noise", that are filtered by a speckle filter, caracterized by its "speckleWindowSize" & "speckleRange" parameters => see openCV's documentation on that link text.
First of all, what is Speckle noise and what causes it ?
Secondly, in the above link, you can find the below definitions (which don't really explain anything and just give ranges that seem to come from nowhere) :
while the famous "Learning OpenCV" book from Gary Bradski and Adrian Kaehler gives a totally other range for speckleWindowSize :
By testing it, it seems that I can effectively go up to a 200 window size, but if that is represented in pixels, isn't that a huge window ?
Also, the above text gives an explanation on what speckle is. As I understand it, we juste have small values of disparities for the background and large values for the foreground, which is exactly what is supposed to be...? Therefore, I don't understand why it is considered as noise and why we should filter it ?
Any help would be appreciated,
Thank you.