*
* @return a prototype that is used to construct new shapes
*/
protected static CTPicture prototype(){
if(prototype == null) {
CTPicture pic = CTPicture.Factory.newInstance();
CTPictureNonVisual nvpr = pic.addNewNvPicPr();
CTNonVisualDrawingProps nvProps = nvpr.addNewCNvPr();
nvProps.setId(1);
nvProps.setName("Picture 1");
nvProps.setDescr("Picture");
CTNonVisualPictureProperties nvPicProps = nvpr.addNewCNvPicPr();
nvPicProps.addNewPicLocks().setNoChangeAspect(true);
CTBlipFillProperties blip = pic.addNewBlipFill();
blip.addNewBlip().setEmbed("");
blip.addNewStretch().addNewFillRect();
CTShapeProperties sppr = pic.addNewSpPr();
CTTransform2D t2d = sppr.addNewXfrm();
CTPositiveSize2D ext = t2d.addNewExt();
//should be original picture width and height expressed in EMUs
ext.setCx(0);
ext.setCy(0);