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Updated:
14 February 2003
Disclaimer:With all these enhancements and algorithms, it must be noted that the satellite sensor is broad band and the unique discrimination of surface materials is often limited. At best the presented algorithms are an indication of occurrence of the labelled features and some will be more definitive than others. While we have presented a powerful on-line remote sensing analysis tool, there are limitations of algorithms in terms of accuracy. An understanding of the properties of marine and coastal materials and their interaction to produce a complex signal at the satellite sensor is required to properly analyse the processed imagery. Variability in scene contents will always result in subjective and relative accuracies of imagery.
Mudflats AlgorithmInitial ideas were to use ratios such as TM band5/band7 to enhance muds but it quickly became clear that spectral properties of coastal mudflats varied considerably due to different concentrations of mud, salt and wetness. This means that it was impossible to derive a definitive index for mudflats. Examples of this are shown later. We recommend the use of a colour composite of bands 1,4 and 7, RGB. |
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