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Figure 7: CCD frame of a targeted car 
The second example was a student project and 
relates to the measurement of a car. The 
measurements of targeted points were made semi- 
automatically in 17 CCD camera frames and 
manually in 12 WILD P 31 photographs for 
comparison. The accuracy of the CCD 
measurements as determined from check points 
resulted in RMS values of |i x = 0.40, p Y = 0.75, p z 
= 0.55 mm in object space and p*= 0.9 pm, p = 1.1 
pm in image space with an estimated CTq= 0.55 pm. 
Figure 7 shows one CCD frame of the car.Least 
squares image matching was also applied in this 
example for digital surface reconstruction. 
Differential orthophotos and synthetic images in 
parallel projection have also been derived 
4.3. Surface measurements 
In Gruen, Baltsavias, 7988b a report was given on 
the reconstruction of a human face by applying 
special feature extraction techniques and least 
squares image matching on a CCD camera stereo 
pair. Figure 8 shows one of the original images and 
two derived products (wireframe and Gouraud 
shaded models) assembled on a cube. It should be 
noted that for actual processing structured light 
illuminated images were used. 
The automatic generation of Digital Terrain Models 
is reported in Baltsavias, 1988 and Wilkins, 1990b. 
Figure 8: Human face surface reconstruction. As 
sembly of original image together with 
wireframe model and Gouraud shaded 
model on a cube.