Camera Transition between two cameras

I was playing a [game on gamejolt][1] and I wanted to know how the developer did the film like transitions between cameras and how the camera's height/width would change so naturally from one camera to the other. I know that you can have multiple cameras rendered at once as in my current project, but I don't know the transition worked in the other game, was it an animation, script, or some 3rd party package? Does anyone have any idea? ![alt text][2] [1]: http://gamejolt.com/games/other/electric-tortoise/24547/ [2]: /storage/temp/24601-capture4.png