Precision Processing System (PPS) 
The main function of the PPS is to provide precision rectification of 
images. The geometric corrections performed by the BPS do not take 
account of variations in satellite attitude, altitude and velocity 
since these do not constitute a priori knowledge. The attitude 
measurement data in the satellite data stream is too coarse to give a 
good geometric correction. The PPS uses surveyed ground control 
points to calculate corrections to warp the image to the required map 
projection. 
The PPS is able to perform all of the corrections and enhancements 
listed for the BPS on raw data, or can use bulk corrected data as an 
input. In addition to precision rectification to the Australian Map 
Grid it can provide the following enhancements: 
(a) data drop-out repair (cosmetic); 
(b) haze removal; 
(c) edge enhancement of linear features; 
(d) custom contrast stretching and manipulation to suit particular 
applications; 
(e) full geographic gridding or tick marks; 
(f) full UTM gridding or tick marks; 
(g) variable format text annotations. 
The PPS output is in the form of master negatives on 240mm film 
stock. Scales are infinitely variable in the range 1:1 000 000 to 
1:50 000. 
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PI