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A SYSTEM FOR DIGITAL PROCESSING OF DYNAMIC IMAGERY 
Roderick R. Real 
Photogrammetric Research Section 
Division of Physics 
National Research Council of Canada 
Ottawa, Canada, K1A OR6 
Commission II 
Abstract 
À portable, low cost, digital image processing system for applications 
directed toward solutions in filmless, in-situ photogrammetry of dynamic 
processes is under development. The system, consisting of video rate 
photoelectronic image capture and digitization, digital spatial filters, 
correlator/convolver and displays, is described and some results 
representative of its capability presented. 
1. Introduction 
Measurement, interpretation, classification and control from imagery is 
experiencing a revolution propelled by advances in semiconductor technology. 
The bandwidth of signals which can be digitally processed is now extending 
some operations into the realm of real-time on images of TV frame size (IEEE, 
1981; Lee, 1982). Although this precludes high resolution large format 
images, there is growing scope for application of digital image processing 
techniques directly to certain close range applications where filmless, in- 
situ, réal-time operations and control prevail, as might be expected to be 
encountered in the medical and manufacturing environment. 
Although optical techniques are conceptually more attractive for 2-D 
operations, digital transformation of images proved through the years to be an 
exceptionally versatile, precise and robust technique. Its main disadvantage, 
slowness, is gradually eroding as a consequence of exceptional advances in 
semiconductor technology.  Compelling reasons for processing images digitally 
in photogrammetric applications are to augment human vision, measurement and 
classification tasks without fatigue, data transformation and extraction, and 
fast, accurate recall from previously stored data for comparison or matching. 
Development within our laboratory is aimed at embodying certain existing 
digital image-processing techniques into low-cost, real-time units utilizing 
readily available components for routine use in experiments and apparatus 
employing electronic image transfer. A description of the hardware comprising 
an experimental unit as it currently stands is followed by some examples of 
its capability. 
2. Fast Digital Image Processor 
An experimental digital image processor, Fig. 1(a), is developed to the extent 
that it performs video rate photoelectronic image capture, digitization and 
storage, fast spatial filtering, correlation, convolution, image mixing, 
matching, addition, subtraction and display. Other desirable features 
associated with large image processors may become incorporated in time as 
semiconductor technology evolves. 
System architecture, indicated in Fig. 1(b), features an input or image 
capture section and an output section between which is a fast processor. One 
part of this processor transforms an entire video frame while the branch 
performs more computation intensive operations on a sub-frame portion (window) 
of the whole frame, either in parallel or in series with the whole frame unit.