Has anyone figured the unit and convention of PrincipalPointU and PrincipalPointV ?
For example if PrincipalPointU is -0.17037, this is probably the horizontal offset from the center of the image? but in which units, pixel, mm, inch, sensor width? Does this value go from -1.0 to 1.0 or -0.5 to 0.5 ?
Another example, what would be the principal point values if it was the top left corner of the image? -0.5,-0.5, or -0.5,0.5 or -1,-1 or -1,1 ?
Edit: I am referring to the values in the XMP file exported from RealityCapture.
Edit: Even in the UI it is very confusing, the tooltip is "Deviation of image central point in image pixels", yet the label contains "[mm]" indicating the unit is millimeters. So is the value in image pixels, or in millimeters??
Please sign in to leave a comment.