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The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. Vol. XXXVII. Part B5. Beijing 2008 
acquired using the prototype and some preliminary 3-D 
mapping results are shown. An overall summary is given in the 
final section. 
2. THE MPMS PROTOTYPE - AN OFF-AXIS 
PANORAMIC SCANNING SYSTEM 
2.1 Configuration of the Stereo Cameras 
In a linescan-based panoramic scanning system using an off- 
axis camera configuration mode, there are many ways to 
configure the stereo cameras regarding their heights, rotation 
axes, rotation radius, etc. A geometric model that considered 
these factors was described in Huang et al. (2001). 
Figure 1. Hardware components of the MPMS prototype 
In the design of this prototype, both stereo cameras have the 
same height, share the rotation axis and are equidistant from the 
rotation axis. With this configuration, shown in Figure 1, the 
acquired stereo multi-perspective panoramas will have not only 
uniform accuracy in all 360° directions in each depth, but also, 
in theory, horizontal epipolar lines. This will allow the use of 
simplified algorithms to quickly find corresponding points, and 
provides the potential for onboard applications. 
2.2 Hardware Integration 
The major hardware components of the MPMS prototype 
include stereo cameras (optical system, linear array CCDs and 
housing), a frame grabber, and a support system that includes a 
rotary stage with controller, remote sensing mast, and stereo 
camera bar (see Figure 1). In the prototype we have used only 
one camera. To obtain stereo panoramas, the camera is 
alternately mounted on the opposite ends of the stereo bar. The 
height of the mast is adjustable from 70 cm to 130 cm, and 
different mounting positions on the stereo bar for the cameras 
allow for baseline lengths from 20 cm to 50 cm. Table 1 shows 
the main technical parameters of this prototype. 
Software was developed to integrate the hardware components 
for image acquisition, where the exposure time (also scan time 
of an image line) of the camera and the rotation speed are 
configured to create different resolutions in the horizontal 
direction. The horizontal Field of View (FOV) of acquired 
panoramas (the rotation angle) can be pre-defined in this 
software, and does not have to be 360°. 
Focal Length 
35 mm 
Vertical dimension of CCD 
4,080 pixels 
Channels 
RGB 
Vertical FOV 
64.5° 
Image Columns (360°, varying) 
22,000 (e.g.) 
Data Volume (360°) 
220 MB 
Recording time (10 ms/column, 360°) 
3.3 min 
Table 1 Major parameters of the MPMP prototype 
2.3 Geometric Model of Multi-perspective Panoramas 
The geometric model of multi-perspective panoramas is similar 
to that of single-center panoramas as described in Schneider and 
Mass (2003). It differs, however, in that it has two additional 
parameters: R, the rotation radius, measuring from the rotation 
axis to the camera’s perspective center, and Q, the swing angle 
between the baseline and the camera’s line of sight. The stereo 
computation is based on the off-axis stereo model. 
Figure 2. Geometrical modeling of multi-perspective panoramas 
P (Object point) 
Figure 3. Top view: internal circle represents the trajectory of 
the camera’s perspective center; external circle represents the 
cylindrical panorama