2007 Camry won't start what are main possibilities with this sound?

Headlights turn on, but I’m guessing it’s still a battery problem. Came home late last night and it drove fine, no weird sounds, smooth drive. Wife tried to start it right now and it was just followed with an extremely rapid clicking sound when key was turned. There was no check engine light prior to the car not starting.

Note* It fired up perfectly last night just like it normally does.