2004 
RQ ANIMATED TOOLS FOR ILLUSTRATION, DEMONSTRATION AND STUDY OF 
GEOMETRIC RELATIONS IN PHOTOGRAMMETRY AND REMOTE SENSING USING 
ta MS-EXCEL 
2001 ^ ; ; Yi ; ; : à 
any) K.A. Grabmaier, International Institute for Geo-Information Science and Earth Observation (ITC), P.O.Box 6, 7500AA 
Senf. The Netherlands, grabmaier@itc.nl 
ition 
4, 
KEY WORDS: Visualization, Animation, Geometry, Orientation, Teaching, Photogrammetry, Remote Sensing. 
omo 
lose 
tool ABSTRACT: 
IXth 
For teaching about the geometry of Remote Sensing images, Orientation and Georeferencing problems spreadsheet graphics were 
used for visualization of situations in three-dimensional space. They visualize the situation during acquisition of Remote Sensing 
"ical images and demonstrate the effect of changes in the orientation parameters onto the image geometry, and show the influence of 
pert errors in the orientation parameters on the geometry of the reconstructed object by stereo-restitution. The relevant parameters 
Sixth (viewing, orientation and errors in the orientation) can be changed by macros in a continuous fashion and the graphic is continuously 
icial updated. In this way a movie-like effect is obtained. Also other spreadsheets were made, e.g. one showing the rotating earth and an 
orbiting satellite as in a movie (with spherical globe and circular orbit, but all other parameters can be changed by macros). 
Ther RESUME : 
nce, 
Pour enseigner la géométrie des images télédétection ainsi que des problémes d'orientation, on utilise les graphiques des feuilles des 
calculs pour visualiser la situation en 3 dimensions. On peut observer la situation des prises de vues des images télédétection, et 
hing démontrer les effets des changements des paramétres d'orientation sur la géométrie des images. Les graphiques montrent l'influence 
elief des erreurs des paramétres d'orientation sur la géométrie des objets reconstruits par méthode de restitution stéréoscopique. Les 
fies. paramètres les plus importants (présentation, orientation des images et leurs erreurs) peuvent être changés de manière continue par 
des « Macros ». En même temps le graphique est modifié. De cette façon, on obtient un effet « cinéma ». On a aussi développé 
f d'autres feuilles des calculs, par exemple un satellite qui orbite un globe tournant. (Le globe est sphérique et l’orbite est circulaire, 
c mais des « Macro » permettent de changer tous les autres paramètres.) 
KURZFASSUNG: 
4. « = . * = > : y : . 
(2), Für den Unterricht über die Geometrie von Fernerkundungsbildern und Orientierungsprobleme wurden Tabellenkalkulations- 
Graphiken eingesetzt zur Darstellung von 3-dimensionalen Situationen. Sie zeigen die Aufnahmesituation und den Einfluss der 
Parameter auf die Bildgeometrie, sowie die Auswirkung von Orientierungsfehlern auf die Geometrie des wiederhergestellten 
Objektes. Die relevanten Parameter (der Darstellung, der Orientierung der Bilder und deren Fehler) kónnen mittels Makros 
an kontinuierlich verändert werden, wobei die Darstellung folgt und die Veränderung wie in einem Film abläuft. Es wurden auch 
tion andere derartige Graphiken gemacht, z.B. ein Satellit, der die sich drehend Erde umkreist (mit kugelfórmiger Erde und kreisfórmiger 
14 Satellitenbahn, aber alle anderen Parameter mit Makros veränderbar). 
ong INTRODUCTION 
eck. Especially for teaching about geometry and orientation of 
For most of my teaching I normally prepare the teaching aids images good visualizations are very essential, but it is often 
EI by myself. With the change from overhead projector to digital difficult to choose the right composition and viewing angles for 
slides I didn’t scan my old graphs, but prepared new ones (in a scene one wants to show. The spreadsheet was thus organized 
MS-PowerPoint). to allow easy changes of the viewing parameters, but also the 
ion, orientation parameters of the two cameras were changeable. 
1010, First I supported my drawings with simple calculations, which I 
did in MS Excel. (I often use Excel, when others would use a Soon this was considered not convenient enough and the 
calculator.) From this point it was a small step to visualize the parameters were made changeable by macros. Also the images 
ond calculated lines as a graph in Excel. When I also succeeded to in the image planes of the cameras were shown in separate 
Tay, import the graphics into MS PowerPoint, soon the functionality graphics sheets. 
aler, grew, as with every realized improvement the desire arouse to 
add yet another functionality. Next changes to the orientation parameters were introduces and 
: the images projected back to the object space and the 
m Originally I used a simple parallel projection, but for a teacher reconstructed object shown. 
of image geometry the formulas for a perspective view should 
not give any problem, and a perspective view gives a much 
more natural appearance. In addition to a simple terrain object, 
Which is shown as *wire frame" from a list of coordinates, the 
spreadsheet shows two cameras above the object with the image 
of the object in the image plain. 
Typical “objects” shown in these graphics are: 
e A box connecting points in a rectangular pattern of 
3x3x2 
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