How to display an image as application badge on iPhone or iPad?

On this page it says:

Additional Information Applications can offer up to three types of push notifications:

• Sounds: Plays an audible alert
• Alerts: Disp开发者_Python百科lays an alert on the screen
• Badges: Displays an image/number on the application icon

Source: http://support.apple.com/kb/HT3576

How do we do that?

Thanks,

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I think that information in confusing on Apple's part, but you can't use an image as a badge. The red badge circle with the number is what they are referring to as the "image".