ad (ii): Imaging configurations: 
In close-range photogrammetry various image acquisition 
arrangements are common. CRISP addresses the following confi- 
gurations. 
* Single cameras (e.g. amateur photograph of car-accident 
where one can assume that the scene of interest is a 
plane, namely a road surface ); 
* Single stereo-pair with arbitrary exterior orientation 
# 
Blocks of images: 
strips 
common blocks (consisting of several strips) 
other blocks such as e.g. a series of images presenting 
all sides of a single object, or repeated exposures 
of the same object (multiple overlap). 
ad (iii): Data Processing: 
The analysis of the data in close-range photogrammetry is very 
diverse and specific to each case. The end product will mostly 
consist of coordinates in the object coordinate-system, such 
as of individual points, of digital vector data such ‘as 
contour lines, and of shape descriptions such as lengths, 
slopes, digital height models. 
Organisation of CRISP: 
The block diagramm in Figure 2 illustrates the main flow of 
operations in CRISP. 
A path exists from (to) the initialisation/project - 
formation module to (from) any other module of the system. 
In the event of a single image task, a single photo stage 
only will be used with binocular observation of this one stage. 
The stereo case uses both plate carriers in the conventional 
way. Also the block is essentially an expansion of the 
stereo-comparator concept. 
In all cases a bundle adjustment is the ultimate method 
of relating image, image pair and block to the object data. 
However, preliminary computations are needed. In the single 
image case, a DLT or 2-d collineation model is used to generate 
approximations of inner and exterior orientation parameters; 
the same applies to stereo data if no inner orientation is 
known. Otherwise the approximations result from a space 
resection with 3 points for a single photograph, or a relative/ 
absolute orientation for the stereo model. 
The image block is conseptually a set of stereo models to 
generate precise image coordinate measurements and approxima- 
tions for the unknowns. 
In the case of a single image or stereo model set-up with 
known camera, inner and exterior orientation, the preliminary 
and bundle adjustment steps do not apply. Instead one directly 
proceeds to stereo plotting after establishment of the inner 
orientation. 
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