iframe printing problem (safari)

I am trying to print an iframe with this function:

   function printIframe(id) {

      iframe = document.frames ? document.frames[id] : document.getElementById(id);
      ifWin = ifra开发者_如何学运维me.contentWindow || iframe;
      iframe.focus();
      ifWin.printPage();

   }

This code successfully prints iframes in all browsers. The problem is that safari will not print some images. Some images will print, whereas others will just print blank spaces.

Has anyone ran into this problem before?