@StevenPuttemans thank you very much for your reply :) to be very specific the object I mentioned in the above question is a railway track, well I would like to measure the perfect gauge(perpendicular length between edges) by a stereo vision cam. So far from my knowledge the depth can be calculated by the disparity maps.I am wondering about how to make a system when rolled over a railway track should sense the gauge difference or error between the respective tracks.Sorry in advance if my imagination doesn't make any sense :). Please please give me a lead to start off...

How to find the real geometry in terms of length, breadth from the disparity map in stereovision? specifically in python.

thank you in advance.

Well, I would like to ask, is there any function in opencv which can find the exact length and breadth of any object in a video or image.

thank you in advance vibin

@pedrobatista thank you for raising extremely good questions that really matters in my project. well,micrometer sounds nearly impossible since I have to use microscopic lenses, I think I should step back to millimeter accuracy and I am working and trying to fix the issues, I will definitely let you know if I get any useful leads thank you so much

GiLevi please go through the binary image I had uploaded just before, waiting for your valuable comment thank you!

when you convert in to binary this is how it looks like and I need to measure the exact perpendicular distance between two edges and I am worried about getting the absolute points on the respective tracks to determine whether it is perpendicular or not, kindly reply

Thank you berek, microscope is not in the scope even if it is possible to measure in millimeter precision ,fair enough for me to proceed and I need a portable device to port the algorithm, I has thought about working with beaglebone-xm board which is supported by opencv and the maximum compatibility of camera is 5 MP on that board, well, I went through stereo vision principle too and found it quite applicable for my application could you please give me your input in that regard.

Thanking you in advance !

I would like to know, can canny edge detector be used to measure the real distance between two parallel edges, say my project is to measure the distance between the rail tracks, which has to have an accuracy in micro meters. My question is, is there any possible algorithms in opencv which can get the absolute distance measurement in micrometers, the term micrometer is of most importance.I look forward for an answer.I am able to detect the edges but mere edge detection doesn't give me a solution for my problem.Please let me know if it is possible I can go forward with confidence.

Thanks a lot in advance opencv.org