3D MONOCULAR RESTITUTION APPLIED TO SMALL FORMAT DIGITAL AIRPHOTO AND LASER SCANNER
DATA
E. A. Mitishita*', A. L. Machado * , A. F. Habib”, G. Gonçalves “
* UFPR, Federal University of Parana, Department of Geomatics, Curitiba, Parana, Brazil, mitishita@ufpr.br, alvaroml@ufpr.br
? UCalgary, Department of Geomatics Engineering, University of Calgary, Calgary, Alberta, Canada —
habib@geomatics.ucalgary.ca
WG 111/1 Sensor Pose Estimation
KEY WORDS: 3D Monocular Restitution, Laser Scanner, Low Cost Digital Camera and Vector Mapping.
ABSTRACT:
The utilization of the low cost digital small format camera for the obtainment of space information of the terrestrial surface tends to
increase in the current days. This is due to the increase of the resolution, low cost and good geometric stability for mathematical
parameters that define the interior geometry. The data set point, with height surface information, derived from the laser scanner, has
improved the accuracy. Also, the development of this new technique has improved the existent methods applied to obtainment of the
space information for several engineering applications. The development of new photogrammetric procedures applied to obtainment
of information of the terrestrial surface that present facility, less qualified operational dependence and low cost in the productive
process, is being more and more requested in the current. This paper shows the development of the methodology used and the results
obtained from 3D photogrammetric vector mapping using the monocular restitution; digital aerial images obtained from low cost
small format camera and data set height points deriving from laser scanner system. The digital aerial images were provided by an
aerial survey performed with digital small format Sony camera, model DSC-F717, resolution of 5.2 Mbytes, CCD dimension of the
2560 x 1920 “pixel”. The air survey was performed in an approximate height flight of the 750 meters. The pixel resolution in terrain
is approximately 25 centimeters. The height data set points were derived from laser scanner air survey with 1000,00 meters of the
height flight. The resolution of the pixel size in terrain is approximately 50 centimeters. The System used is OPTECH/INS GPS
APPLANIX, property of the Technology Institute for the Development — LACTEC — UFPR. This paper presents the height
interpolation procedures and mathematical algorithms and techniques development used for both with and without height features
extraction. The procedures were implemented in the computational program (Digital Monoplotting) and it was developed in the
Graduation Program Course in Geodesic Sciences in the UFPR. Control points were used to determinate the exterior orientation of
the images and the compatibility of the height data set points. The three-dimensional coordinates of points of the entities were
compared. The points were derived from the vector mapping produced by 3D monocular restitution and the conventional 3D stereo
restitution performed in the Zeiss Planicomp with conventional metric photos (camera WILD RC-10 and scale of 1/6000). The paper
presents the results performed in the comparisons.
1. INTRODUCTION
Small format digital cameras have currently become popular
instruments, with spatial resolutions similar to traditional
cameras operating with photographic film. The utilization of
this sensor in engineering projects that employ terrestrial or
aerial images to obtain metric information tends to increase in
photogrammetric applications. This is due to the continuous
increase of the resolution of the sensor element based on CCD
(Charged Coupled Device) or CMOS (Complementary Metal
Oxide Semiconductor), along with the low cost and higher
geometric stability of the image. One also notices the constant
development of analytical photogrammetric procedures based
on digital images, thus causing the practice of Photogrammetry
to be more utilized.
The utilization of non-conventional digital cameras in
photogrammetric applications demands accurate camera
calibration procedures so as to determine the defining
parameters of the projective geometry (HABIB et al. 2003).
Altimetric information of the terrestrial surface obtained from
laser scanning has improved the accuracy of the digital model
of the surface (DMS) and it has brought development and
improvement of new photogrammetric techniques to obtain
spatial information of the terrestrial surface (See Ackermann
1996; Baltsavias 1999). Presently, the development of
photogrammetric procedures to obtain information about
terrestrial surface presenting easy features, less qualified
operational dependence and low cost in the productive process,
is being more and more required
This paper presents the development of methodology and
results obtained from the vector tri-dimensional
photogrammetric mapping supported by 3D Monorestitution
and from digital aerial images obtained with small-format
cameras and altimetric data from laser scanning system. A
digital image proceeding from an aerial covering performed
with a small-format digital camera, Sony DSC-F717 model, 5.2
Mbytes resolution, CCD of 2560 x 1920 Pixels, was utilized.
The aerial coverage was conducted in an approximate flying
height of 750 meters, resulting in pixel with approximate
resolution on the terrain of 25 centimetres.
The digital surface model (DSM) originated from a survey
carried out by laser scanning system, in flying height of 1000
meters, with approximate resolution of 0.5 meters, obtained
from OPTECH/INS GPS APPLANIX System, belonging to the
Institute of Technology for Development - LACTEC — UFPR.
International Arch
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