USING PANORAMIC PICTURE FOR MEASURING PURPOSES

References: 14th International Multidisciplinary Scientific GeoConference SGEM 2014, www.sgem.org, SGEM2014 Conference Proceedings, ISBN 978-619-7105-12-4 / ISSN 1314-2704, June 19-25, 2014, Book 2, Vol. 3, 375-382 pp

ABSTRACT
This paper deals with a role of panoramic picture in object 3D documentation. Four panoramic interior images were used for 3D documentation and ground control points were surveyed for proportion determination. Ground control points served as a base for pictures screening centre definition. Panoramic pictures are perceived as a set of surveyed directions and zenith angles. If the projection of panoramic picture is known one receives a set of ground control points’ surveyed directions and zenith angles. It is necessary to find angles between panoramic images and appropriate geodetic and coordinate system. The knowledge of these angles enables one to determine the location of projection centre in a coordinate system. Iteration was used as a method of angle calculation. The X and Y axes inclination in coordinate system was determined together with the orientation shift of the panoramic picture set (turning around Z axis). The location of panoramic picture projection centre in coordinate system is determined by Mean Squared Error equalization. Two methods were used for detailed survey point coordinates calculation – determination of detailed survey points from height base and the Mean Squared Error equalization. The first method was used in areas with sharp intersect angle on detailed survey point, iteration methods has been used in this calculation. For Mean Squared Error is necessary to determine the approximate coordinates of detailed survey point using forward intersection. The Mean Squared Error equalization was performed using iteration methods. An experiment has been carried out - lengths between points of real objects were measured and these were compared to calculated lengths derived from panoramic picture. Wide-angle lens and telephoto lens were tested and their effect on the measured lengths accuracy was analyzed (is the deformation of panoramic picture bigger when acquired by telephoto lens?).

Keywords: panoramic picture, GigaPan Epic Pro, Mean Squared Error