how can I find the mathematical principal of the opencv function stereoRectify()

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I know how to use the function stereoRectify(), but I also want know that how it works. I know, of course, that I can learn about this by reading the code, beacuse opencv is opensource. but I am not a good code-reader, ok, I admit that I am a poor code-reader. I tried to search this on the internet, but I didn't get any useful infromation. I also can't find any introduction about this in the opencv online documents. so is there anyone could give some information about the mathematical principal of this function? whatever it is, any form is ok( e.g. paper ,blog). thx:)