Land use classification of polarimetric SAR data by visual interpretation and comparison with an automatic procedure

A study is presented in which several representations of polarimetric SAR data were evaluated for the purpose of obtaining land use classification. Two methods comprising visual interpretation and an automatic procedure were used. For the study, fully polarimetric SAR data with a resolution of 3m were obtained with the Dutch PHARUS sensor from a test area in the Netherlands showing various classes of land use. The land use classes consisted of bare soil, water, grass, urban areas, and forest. The visual inspection was performed by different groups of non-expert interpreters for each representation. It was found that people are quite successful by visual interpretation in performing land use classification using SAR data. Multi-polarized data are required for this purpose, although these data need not be fully polarimetric, since the best results were obtained with the hh- and hv-polarization combinations displayed in the red and green colour channels. The results show that land use classification by visual inspection is more effective than the automatic classification procedure.