Ono Tetsu 
  
  
Left Image Right Image 
( Black points: Check Points White Points: GCPs ) 
Figure 2: Test Images and Measured Points 
Table 2: Accuracy of Ortho-Image and the Orientation (pixel) 
Left Image Right Image 
Direction flight | scanning | flight | scanning 
Orientation | 0.922 0.524 0.763 0.625 
Ortho-Image | 0.923 0.652 0.755 0.711 
  
  
  
  
  
  
  
  
  
  
  
5 IMPLEMENTATION 
The authors developed the digital stereo plotter KYOTO-P, which can handle satellite imagery with 2D afline 
projection model. It is mainly written in interpreter language ” Tcl/Tk", but it is fast enough on PC with 
Pentium 200Mhz. KYOTO-P uses 3D glasses Crystal EYES for stereo viewing and another special device 
is not required. KYOTO-P consists of four components: orientation module, epipolar resampling module, 
digital stereo comparator and digital stereo plotter. The whole process is as follows. As the first step, relative 
orientation points and GCPs are identified on the original satellite images with digital stereo comparator. 
Secondly, epiplar resampling module generates epipolar resampled image based on affine projection. Orientation 
calculations are carried out to determine the relationship between the epipolar images and object space. Mapping 
operator stereoscopically views the epipolar images, scrolls the images in real-time and compiles topographic 
maps on the monitor. 
6 CONCLUSION 
This paper has reported on the application of the 2D affine projection model to satellite ortho-image generation 
and also has referred to real-time positioning. It has shown that 2D affine projection model has advantages in 
stability and speed in these application. The model has some limitations in the employment, but the model 
are efficiently applicable to small area mapping. Also, our testing has supported the contention that SPOT 
ortho-imagery to 1-pixel ground accuracy can be produced using ground control and DTM data from existing 
published map of the Japanese large scale map series. Considering the characteristics of affine based approach, 
2D affine model is also appropriate for high resolution satellite imagery. Furthermore, the module based on 
the model has been implemented easily on softcopy photogrammetric workstations and has worked very well in 
Speed. 
REFERENCES 
D. J. Gugan, 1987, Practical Aspects Of Topographic Mapping From SPOT Imagery, Photogrammetric Record, 
12(69): 349-355 (April 1987), pp.349-355 
D. J. Gugan and I. J. Dowman, 1988, Topographic Mapping from SPOT Imagery, PE & RS, Vol.54, No.10, 
Octover 1988, pp.1409-1414 
  
676 International Archives of Photogrammetry and Remote Sensing. Vol. XXXIII, Part B3. Amsterdam 2000. 
Df) "F. 
RS