The version of GraphicsMagick you have installed may be limiting you to 8-bit-per-pixel images. Often we have scientific data that is 16-bit-per-pixel images. You can compile GraphicsMagick for your system using the following options:
./configure --with-quantum-depth=32 --enable-shared --disable-static
You will possibly get a “SketchUp was unable to initialize OpenGL” error when trying to use SketchUp 8 under Wine 1.5 (and sometimes under Windows XP on older hardware).
To fix this OpenGL error for SketchUp8 on Windows XP or Linux/Wine, type “regedit” and then edit the key:
to have a value of 1.