2006.08.18 20:04 "[Tiff] help about tiff", by fayssal james

hello

my name's fayssal and am a student working on a project in order to handle geotiff images that are provided by MSG to the spatial researches center in morocco and as you probably know the images are classified by channels,there are seven and i am interested in channel 1 and 3 so i can realise the discrimination of snow and its temporal progress.so i managed to calculate the NDSI (normalised difference snow index) wich is in fact p1-p3/p1+p3 where as p1 and p3 are the values of the pixel p in channel 1 and 3 where the images are in gray 16 bits

my problem consists in the use of geotiff library and how to get the value of pixels and calculate the NDSI i would be glad if you can provide me any help

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