How to convert the RGB values of an GdkImlibImage

[venugopal <venu iiithyd ernet in>]

I would like to find out the technique of changing the attributes of an
GdkImlibImage, and whether a GdkColor can somehow be used in order to
change the attributes of the imgae. I have used the gdk_imlib_copy image
and gdk_imlib_copy_mask functions to create the pixmap and bitmap
respectively, and then used these to create a pixmap widget with the
gtk_pixmap_new function. I would like to know find out how to change the
colors/other attributes of this widget/image. I am new to gtk, so please
excuse me if my doubt sounds trivial/silly. Thanks in advance for any
help.

						yours,
						venu