Laser Scanned Imaging System

Project Overview
This project was an upgrade to an existing control/analysis program for a high-end, laser scanned imaging system. The hardware unit was capable of high-speed, variable resolution scans using either radioisotopic or chemiluminescent samples. As originally configured, the analysis package allowed the user to isolate a region of the scanned iconic image using one of a number of predetermined planar shapes such as rectangles or ellipses. The largest part of the upgrade consisted of adding a freehand draw routine that would allow the user to isolate an arbitrarily shaped, closed region containing image elements of interest. The user could then perform various background manipulation and image enhancement filter operations on the result.

Software Design and Methodology
This project was well specified from the outset and contained no high-risk elements other than simple understanding of an existing code base. At the time the project was assigned, the existing code base consisted of more than 200,000 lines. The software product was mature, had been through many previous revisions by a succession of programmers and therefore constituted something of a challenge in terms of program understanding. Therefore, we approached this project in two phases, a code familiarization phase and a design/implementation phase. No significant work was done on phase two until the first phase, code base familiarization, was complete. Because little usable software documentation existed, a number of code analysis tools were either obtained commercially or constructed (mostly using scripting languages such as AWK). Because of the complexity of the existing code base, the familiarization phase required a full four months to complete. With phase one complete, the remainder of the project proceeded using a classic waterfall development model.

Project Outcome
The code familiarization phase of this project concluded within only four months. At this point, understanding of the code base was excellent and, as a bonus, the project documentation was substantially updated. The design and implementation phase was then estimated at eight months. We finished in seven. The freehand draw feature was a well-received aspect of the subsequent release of the product.