Hi,
with the next krpano version 1.21 measurements in 3d space will be very easy,
but in any case you would need a depthmap or 3d-model for the pano image.
Just a pano-image alone will be not enough to be able to get any distances.
For more information on how to get depthmaps or 3d-models please see here:
krpano Depthmap Support
Best regards,
Klaus