title: How can we compute rotation and translation two stereo cameras to use in opencv StereoRectify(r,t argument)
body: <p>I know that I can compute the rotation and translation about two stereo cameras using having some real 3d points and then calling solvepnp function in opencv but I don't have these 3d points.
  I have intrinsic parameters and extrinsic parameters for each images.
  Also I have some 2d points in left image and their corresponding points in right image.
  If I have the rotation and translation about two stereo cameras, I will be able to use stereoRectify function and then can compute 3d real coordinates of some 2d points in images.
  I searched a lot in different sites but didn't find a routine and straightforward way to compute 3d real coordinates(x,y,z) from 2d points in two stereo cameras.</p>