how to rotate an image

I have a few images attached below. I want to align the images.

Say I want to align the second image attached below like the first one. Can anyone help? plz!!!

[Mohammad Abouali]

There is only one image attached!

[nkumar]

sorry for not attaching,assuming the above object(tomato) in image is rotated by some angle (angle is not known),how to align it to original image,kindly help

[Image Analyst]

By the way, the image is not rotated - the subject is. There's a difference. Follow the examples for imregister() or friends, and give us your code.