Software installation tricks
Building OpenCV on Ubuntu 10.10 from svn on 2011-January-31 gives the error:
'gdk-pixbuf/gdk-pixbuf.h: No such file or directory'
It seems that that file was moved somewhere else. As a quick fix, you can create symbolic link where the file is needed:
sudo ln -s /usr/include/gdk-pixbuf-2.0/gdk-pixbuf /usr/include/gtk-2.0/gdk-pixbuf