On Nov 9, 2011, at 5:43 PM, Puneet Kishor wrote: > I am looking for some recent tutes on rendering ERDAS .img files. A bit of > the background: > > I inherited these data as an ArcMap .mdb dataset which has metadata.xml, a > few other sundry files, and inside a directory with .idb extension, many more > folders, each containing a .img file, and a corresponding .rrd and .xml file. > A simple layer definition like so allows me to get the tiles displaying in > the browser (via OpenLayers) -- > > LAYER > NAME "lyr" > TYPE RASTER > DATA "foo.img" > PROCESSING "SCALE=AUTO" > STATUS ON > OFFSITE 0 0 0 > END > > But, the tiles don't make for a continuous image. I can see the tile > boundaries. Besides correcting that, I would also like to be able to apply > different color ramps, and, finally, I would like to be able to query either > single pixel values (click on the map and get the underlying value), or some > kind of stats on pixels in an area. > > Would appreciate any tutorials/write-ups if anyone has done this. >
I solved the above by specifying a PROCESSING directive with appropriate min and max values, and now I get a nicely rendered image. However, I get the following in the ms logs -- > [Thu Nov 10 12:45:43 2011].545705 LoadGDALImage(layer): NODATA value > -3.40282e+38 in GDAL > file or PROCESSING directive largely ignored. Not yet fully supported for > unclassified scaled data. The NODATA value is excluded from auto-scaling > min/max computation, but will not be transparent. In this particular dataset, the NODATA value is -3.40282e+38. It well might be different in a different dataset. I am assuming MapServer is carping because I could have set NODATA value somewhere, but didn't, because I don't know how to do that. How do I prevent this error message? Additionally, my rendered image is grayscale. How can I apply a color ramp to this image? For example, instead of from white to black, I would like it to be from white to red or black to yellow (or whatever). Is there a way to do this without having to specify a color value for each of the 256 pixels? -- Puneet Kishor _______________________________________________ mapserver-users mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/mapserver-users
