It extracts into a file an enhanced metafile or device independent bitmap depending on the type of GraphObj.
(which could have been generated, e.g,, by pasting a picture)
BOOL ExtractImageToFile( LPCSTR lpcszPathName )
TRUE for success
GraphLayer lay = Project.ActiveLayer();
grEMF = lay.GraphObjects("EMF");
BOOL bRet = grEMF.ExtractImageToFile("c:\\myfiles\\myemf.emf");