Mirage is described as 'fast and simple GTK+ image viewer' and is an app in the Photos & Graphics category. There are more than 25 alternatives to Mirage for a variety of platforms, including Windows, Linux, Mac, Xfce and PortableApps.com. The best alternative is IrfanView. It's not free, so if you're looking for a free alternative, you could try nomacs or ImageGlass. Other great apps like Mirage are XnView (Free Personal), JPEGView (Free, Open Source), Preview (Free) and PhotoQt (Free, Open Source).