710 
Petsa, Kouroupis, Karras 
For this latter alternative, which has been adopted here, the basic process is as follows according to Fig. 6. Images 1 to n have been 
acquired from the same perspective centre O with considerable overlap (> 50%) and, for the sake of simplicity, with the same camera 
constant c. Thus, the n images have been produced by exactly the same bundle of rays through O and, consequently, are projectively 
related to each other. Accordingly, they can be rectified onto a plane with 2D projective transformations and then mosaicked, to form 
a much “wider” central projection. The plane of the central image A usually serves as the projection plane to avoid extremely strong 
perspective distortions and very large panoramic images. The projection may be performed either through the collinearity equations 
(whereby, for instance, a different panoramic image constant cP can be used) or through the 2D projective equations, conventionally 
applied in photogrammetric rectification. In the last case, not only the exterior but also the interior orientation of the resulting 
panoramic image is that of the reference image A. 
Figure 7: The images used for the creation of the panoramic image (five images were rectified with respect to image A) 
The six images shown in Fig. 7 were rectified and matched to create the panoramic image. They had been taken using a small format 
amateur camera with a wide-angle lens (f = 24 mm). All images were projectively fit to the reference image A, whose interior and 
exterior orientation was again found via its vanishing points, and then merged into a panoramic mosaic of dimensions 11656 x 6054. 
The resulting colour panoramic image is shown in Fig. 8. As the orientation of reference image A also describes the orientation of the 
panoramic image, the principal point of A was identified and transferred onto the panoramic image (x 0 = 6060, y 0 = 3900). 
Figure 8: The initial panoramic image 
The last step for producing the final panoramic image consisted in back-projecting onto it the textured (grayscale) 3D model of the 
building using the orientation data of the panoramic image. Finally, the resulting “augmented” image was locally processed to allow 
a smooth fit of the reconstructed building into the image. A part of the final image can be seen in Fig. 9. 
Figure 9: Part of the final panoramic image 
5. GENERATION OF THE VIDEO SEQUENCE 
Finally, the sequence frames were generated from the augmented panoramic image. Following Fig. 10, the panoramic image has a 
known rotation matrix Rp(o)p, (J)p, k p ) and an image constant c P which are those of the reference image. It was decided to produce 
frames 1 to n which would have no rotations with respect to the object system except for a rotation f about the vertical Y-axis. Thus,