Katy Perry belts out another massive hit.

This image appears in the gallery:
Katy Perry Live At The Summertime Ball 2012 - Pictures

1. 
2. 
3. 
4. 
5. 
6. 
7. 
8. 
9. 

10. 20 images

See the full gallery: Katy Perry Live At The Summertime Ball 2012 - Pictures