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I'm new to QGIS and GRASS. I'm trying to do an image classification and it seems that the method I need is not within the GRASS toolbox in the QGIS . So I decided to use the standalone GRASS version that got installed when I installed QGIS. I created a new project mapset and region and I was able to import the images and create an rgb composite using r.composite - However I'm not able to display them. I have the images activated (with the check box) click on the "display map" icon but nothing happens. When I move the cursor over the map display window, the coordinates showing are correct if I use the querying tool the command says d.raster fail. If I check the region parameters with g.region it gives me the correct region of my study area/ image. I re-created the project several times, save it, open it again, and I still have this problem. Even when I click on the Icon next to the image name to check the properties nothing happens...the histogram of the image is empty. If I extract the raster statistics it gives me an output- but with a d.raster fail error as well. I can open the images and do operations with the GRASS tools within QGIS so it seems to be something with the standalone version. Does anyone knows what is going on? Any recommendations? Thanks!

  • Are you sure the original rasters are within your region settings? Please try g.region rast=<your original img> before r.composite, and then display that original to make sure you are in the right place. – Micha Apr 15 '14 at 19:22
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I'm editing this since I figured what the problem was. Sorry I put it as an answer but my first post was done as a guest and I don't know how to edit it.

I installed QGIS through the windows installer and not through the OSGeo4W installer. it seems that with that installation I was missing something called libfreetype-6.dll I uninstalled and re installed through OSGeo4W installer and followed the instructions in

libfreetype-6.dll lost when using GRASS command line

Now the files display properly!

I found that that dll was missing when I tried to set the display monitor as specified here:

d.rast problem in GRASS command line

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