Direct digitizing of forest boudaries from single aerial photographs

Abstract

Aerial photographs are a major source of forest species data for the geographic information system at the Forestry Commission in the Australian state of Tasmania. The traditional process of capturing this data is time consuming and costly relying on expensive single purpose machines and skilled operators. However, the process is justified by the need to remove the photographic distortions exacerbated by Tasmania's rugged terrain.
This paper outlines an innovative new process which allows for the direct digitizing of forest boundaries from single aerial photographs. The PhotoGlS process rigorously applies the photogrammetric tilt and relief corrections after it has been digitised by using a digital surface model. PhotoGlS provides significant cost savings and greater flexibility in data capture.