Salah, On 2/23/06, salah jubeh <[EMAIL PROTECTED]> wrote: > I have an ascii image the have , i have created this image by calculating > the NDVI so the picxel values are from 0-1 also there are oixel has values > -9999 which represent the No nodata_value . > > when i render thes image using mapserver it gives me just black images, i > have checked this image with othe softwares it is correctly created . > > how can i fix this problem.
Two things to check: 1) Do the ascii raster extents match the extent of your mapfile? 2) Did you scale the image according to data range? Since your values go from 0 to 1, you can use a processing directive in your layer to scale the values in that range from black to white: PROCESSING "SCALE=0,1" There's a good how-to on raster access that you might want to check out also: http://mapserver.gis.umn.edu/docs/howto/raster_data Best of luck, -- Matt Perry [EMAIL PROTECTED] http://www.perrygeo.net
