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photogrammetry?, and why not use an established algorithm such as the 2000<br />
vegetation-impervious surface-soil sub pixel analysis techniques published in the<br />
2000 issue of Remote Sensing (Phinn et al)?<br />
In answer to these questions this review will not be considering a history of<br />
photogrammetry other than a general outline of established (traditional)<br />
processing techniques. It will also not be describing some of the segmentation,<br />
target area identification pre-processing methods used in the various studies. This<br />
work is often a major component of this type of analysis. The answer to the first<br />
question is that in general terms this study is photogrammetry but takes as a<br />
starting point controlled photography and captured polygon data so to consider the<br />
body of work underlying theses techniques falls outside the scope of what this<br />
thesis is attempting<br />
The answer to the second question is that this study differs from previous<br />
techniques in that it pre-supposes a large amount of information form the data<br />
(features of the built environment, feature coding, water parcels, forestry parcels,<br />
roads by category, footpaths and buildings by category) so feature capture is not<br />
part of the study. A possible addition to the study would be a consideration of<br />
feature capture using pattern analysis. In particular the identification of out<br />
buildings adjoining existing dwellings would be useful. However, this is outside<br />
the scope of this study. It can be assumed from the outset most of the major<br />
physical features present in the built environment are present in the data in vector<br />
format. This narrows the application of the technique to areas that are covered by<br />
large scale mapping but results in an automatic method for adding data to this<br />
mapping. One possible application is calculating the percentage of hard ground in<br />
a region of interest.<br />
In general terms the study can be seen as specific to urban areas which have been<br />
digitally mapped at a large scale (1:2500 or 1:1000 scales). Arbitrarily segmenting<br />
an image is a technique that has been used in previous studies (Ketting &<br />
Landgrebe, 1976) but this study differs in that the segments are specific small area<br />
polygons corresponding to property divisions and physical features. Results<br />
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