The UFRaw (Unidentified Flying Raw) is a tool for reading and
manipulating raw images from digital cameras. It supports most of the
existing raw formats (any format supported by DCRaw). UFRaw can be
used on its own or as a Gimp plug-in.

UFRaw requires gtkimageview to include the image preview window. You
can build it without gtkimageview (run with GTK=no) but you'll only
have command line interface to UFRaw.