Multi-Temporal, Multi-Angle Evaluation with CHRIS of Coastal Forests

The Compact High Resolution Imaging Spectrometer (CHRIS) is aboard the ESA PROBA satellite. CHRIS acquires imagery from 415 nm to 1050 nm in five preprogrammed modes. In mode 4, CHRIS acquires 18 bands with emphasis on the red-edge at the full spatial resolution of 18 m. CHRIS acquires 5 hyperspectral images over an angular range of 55 degrees along track. In 2004, five clear CHRIS image sets were acquired throughout the summer over the Greater Victoria Watershed District (GVWD). These CHRIS acquisitions were undertaken for our Evaluation and Validation of CHRIS for National Forests Project (EVC). This paper reports on the analysis of these CHRIS data for creating forest data products for species recognition for sustainable forest management. Emphasis has been given to the utilization of the multi-angle multi-date characteristics of these data takes. The multi-angles of CHRIS improve the accuracies of forest species recognition and stand densities compared to a nadir view only. Testing on five dates saw an average overall accuracy improvement of 14.3% for non-aggregated results and 8% improvement in the aggregated results. Combining multi-date nadir imagery also provided an improvement in classification accuracy by 14.3% and the non-aggregated accuracy by 10%.