I have used OpenCV library to for Stereo Camera Calibration and disparity map estimation. I used the tutorials available in OpenCV 3.3.1 documentation. For example, for disparity I have used the code from the following link:
https://docs.opencv.org/3.3.1/d3/d14/tutorial_ximgproc_disparity_filtering.html
It is working but I can't find detils of what is happenning in the functions used in the code such as left_matcher->computer or createdisparityWLSfilter. I want to read the theory behind these fucntion. So here I am looking for a good link or suggestion for that. I came across the following book:
http://shop.oreilly.com/product/0636920044765.do
But I am not sure if this is the correct resource to read about details of opencv function. Any help is appreciated.