Pattern recognition in Idrisi32

The Idrisi32 program offers an extensive array of tools for pattern recognition.  I imported a bitmap version of the subject image into Idrisi32 and tried many of the GIS Analysis tools. Shown here are samples of the Sobel edge extraction tool and the fractal dimension texture analysis tool applied to the subject image. In general, the tools were able to adequately separate water from vegetation but they were not able to separate the vegetation types nor was the road easily distinguished from the water.

Filter > Sobel edge extraction

Texture analysis > fractal dimension

After extensive trial and error, I decided, that if my eye could distinguish between the grassy uplands and the cattails, then I should utilize that ability along with the tools provided by the programs available to me for photo interpretation. Thus, I developed a technique that allowed me to make the major distinctions between vegetation types and then use the tools available in the Paint Shop Pro™ and Idrisi32 software.

next page