How to add Icon for application in itunes?

I have signed application with adhoc distribution profile. i can install the application to registered devices.the only minor problem is in tunes the application is not seen with icon that i have gi开发者_JAVA技巧ven to application.

---

The icon used in iTunes is defined by the "iTunesArtwork" file, which should be a 512x512 PNG file without the png extension (the icon is 57x57 -- 114x114 for Retina)

See here in Apple's doc for more details.