HIGH RESOLUTION MAPPING USING CCD-LINE CAMERA AND LASER SCANNER
WITH INTEGRATED POSITION AND ORIENTATION SYSTEM
R. Reulke* *, A. Wehr”, D. Griesbach“
* Institute for Photogrammetry, University of Stuttgart - Ralf.Reulke@ipho,uni-stuttgart.de
? Institute for Navigation, University of Stuttgart - wehr@nav.uni-stuttgart.de
© German Aerospace Center DLR, Competence center - Denis.Griesbach@dir.de
Commission III, WG III/6
KEY WORDS: Digital panoramic camera, laser scanner, data fusion, mobile mapping
ABSTRACT:
The fusion of panoramic camera data with laser scanner data is a new approach and allows the combination of high-resolution image
and depth data. Application areas are city modelling, computer vision and documentation of the cultural heritage. Panoramic
recording of image data is realized by a CCD-line, which is precisely rotated around the projection centre. In the case of other
possible movements, the actual position of the projection centre and the view direction has to be measured. Linear moving
panoramas e.g. along a wall are an interesting extension of such rotational panoramas. Here, the instantaneous position and
orientation determination can be realized with an integrated navigation system comprising differential GPS and an inertial
measurement unit.
This paper investigates the combination of a panoramic camera and a laser scanner with a navigation system for indoor and outdoor
applications. First it will be reported about laboratory experiments which were carried out to obtain valid parameters about the
surveying accuracy achievable with both sensors panoramic camera and laser scanner respectively. Then out door surveying results
using a position and orientation system as navigation sensor will be presented and discussed.
1. INTRODUCTION with 3D information of laser scanning surveys very precise 3D
models with detailed texture information will be obtained. This
Generation of city models offering a high realistic visualisation approach is related to 360? geometry.
potential requires three-dimensional imaging sensors with high Large linear structures like city facades can be acquired with
3D resolution and high image quality. Today commonly used ^ panoramic approach only from different standpoints with
sensors offer either a high image quality or a high depth variable resolution of the object. To overcome this problem,
accuracy. Therefore, the idea and the vision of a system was laser-scanner and panoramic camera should be linear moved
borne to integrate available independent measurement systems. along e.g. a building facade. Applying this technique the main
For the acquisition of high resolution image and depth data from problem is georeferencing and fusing the two data sets of the
extended object, e.g. building facades, a high resolution camera panoramic camera and the laser scanner respectively. An
for the image information, a laser scanner for the depth infor- additional accurate attitude measurement is necessary for each
mation and position and orientation system (POS) for measured CCD- and laser-line.
georeferencing must be integrated. The experimental results shown in the following will deal with
High resolution images can be acquired by CCD-matrix andline this problem and will lead to an optimum surveying setup
sensors. Main advantage of line sensors is the generation of — comprising a panoramic camera, laser scanner and a POS. This
high resolution images without merging or stitching of images surveying and documentation system will be called POSLAS-
patches like in matrix imaging. A problem is an additional PANCAM (POS supported laser scanner panoramic camera).
sensor motion of the CCD-line to achieve the second image To verify this approach first experiments were carried out in the
dimension. An obvious solution is the accurate rotation around laboratory and in the field with the Digital 360° Panoramic
CCD-line axis on a turn table as used in panoramic imaging. camera (M1), the 3D-Laserscanner (3D-LS) and a Position and
The depth image or the surfaces of the imaged area can be Orientation System (POS).
acquired very precisely in a reasonable short time with laser
scanners. However, these systems very often sample only depth
data with poor horizontal resolution. Some of them offer
monochrome intensity images of poor quality in the spectral
range of the laser beam (e.g. NIR). Very few commercial laser
The objectives of the experiments are to verify the concepts and
to obtain design parameters for a compact and handy system for
combined data acquisition and inspection.
scanners use additional imaging colour sensors for obtaining 2. SYSTEM
coloured 3D images.
However, with regard to building surveying and setting up The measurement system consists of a combination of an
cultural heritage archives the imaging resolution of laser imaging system, a laser scanner and a system for attitude
scanner data must be improved. This can be achieved by determination.
combining data from a high-resolution digital 360° panoramic
camera with data from a laser scanner. Fusing these image data
* Corresponding author
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