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1037 
INTEGRATED PROCESSING OF TERRESTRIAL 
LASER SCANNER DATA AND FISHEYE-CAMERA IMAGE DATA 
D. Schneider, E. Schwalbe 
Technische Universität Dresden, Institute of Photogrammetry and Remote Sensing, 01062 Dresden, Germany - 
(danilo.schneider, ellen.schwalbe)@tu-dresden.de 
TS-68: SS-16 - Terrestrial Laser Scanning Calibration Techniques 
KEY WORDS: Laser scanning, fisheye lens, bundle adjustment, calibration, registration 
ABSTRACT: 
The paper presents the integration of a geometric model of fisheye lenses and a geometric terrestrial laser scanner model in a bundle 
block adjustment. The model allows for a full integration of hemi-spherical fisheye imagery into terrestrial laserscanner data 
processing schemes. Both the laserscanner and fisheye geometric model are extended by additional parameters to compensate for 
deviations from the ideal model and to optimize the accuracy potential. The results of the combined bundle adjustment are analyzed 
and the advantages of the proposed approach will be discussed in detail. For this purpose, several laser scans with a Riegl LMS- 
Z420i as well as several fisheye images were recorded in a calibration room equipped with ca. 100 reference points. The laser scans 
and the fisheye images were processed in different configurations, the resulting standard deviation of the calculated object point 
coordinates are analyzed and compared. Finally the calibration results of both terrestrial laser scanner and fisheye lens camera as 
well as the accuracy of the observations resulting from the variance component estimation will be presented. The results show that 
the 3D coordinate determination precision can be enhanced significantly by the integrated processing, and that scanner and camera 
aid one another in the self-calibration. 
1. INTRODUCTION 
The combination of terrestrial laser scanner and image data 
presents an interesting option in many applications, as both 
types of data can be used for the analysis simultaneously and 
their properties are largely complementary (e.g. Jansa et. al., 
2004; Ronnholm et. al., 2007). While a laser scanner produces 
precise and reliable 3D information, cameras record colour 
information with a high visual interpretability and a high lateral 
resolution and accuracy. The combination of point clouds and 
image information is therefore supported by several software 
packages. Besides the pure colorizing of point clouds, images 
are used to texturize 3D models for example in cultural heritage 
applications, or to facilitate the interpretation of complex point 
clouds in industrial applications. In each case a strict geometric 
description and subsequently a precise calibration are necessary 
for an accurate geometric referencing between laser scanner and 
image data. 
Figure 1. Laser scanner and camera: Riegl LMS-Z420Ì with 
Nikon D100 (Riegl, 2007): FARO LS 880 with Nikon D200 
and Fisheye lens (Faro, 2005); Nikkor Fisheye lens 8 mm 
Terrestrial laser scanners, which are currently available on the 
market, are often classified by their field of view. There are 
camera-view scanners and panoramic-view scanners covering a 
360° horizontal field of view. Many panoramic-view scanners 
allow for recording of nearly 180° vertically, which means the 
coverage of a full sphere (apart from the bottom area). If a 
digital camera is mounted on a laser scanner with a hemispheric 
field of view (Figure 1) in order to record image information 
simultaneously, only a fisheye lens camera is able to record the 
same vertical field of view in one image. Therefore the 
combination of a laser scanner and a hemi-spherical fisheye 
lens camera is desired (e.g. terrestrial laser scanner FARO LS 
880 (Faro, 2005)). Early photogrammetric applications of 
fisheye lenses are presented in (Beers, 1997). The combination 
of laser scan data and image data in a bundle adjustment is a 
promising method concerning the accuracy of data registration, 
instrument (self-)calibration, reliability and precision of 3D 
object geometry determination. The integration of central 
perspective image and laser scanner data in a combined 
adjustment is also investigated in (Wendt & Heipke, 2006; 
Ullrich et. al., 2003). (Schneider & Maas, 2007) describe the 
integrated bundle adjustment of laser scanner data and 360° 
panoramic imagery. 
2. GEOMETRIC MODELS 
The combined processing of different scans and fisheye images 
requires a superior coordinate system, in which object points as 
well as the exterior orientation are defined. The transformation 
between this coordinate system and the individual coordinate 
system of each scan or image is given by: