[SDL] Does SDL clip surfaces on blitting?

[L-28C]

Hello everyone!

Quick question for the experts: suppose you have a 640x480 image and a 
480x272 screen. If you were to blit the image onto the screen (which is 
smaller than the image), would SDL blit the WHOLE surface onto the 
screen, even the out-of-bounds pixels?

Would it be a good practice if I clipped the image myself? I'm having a 
tough time doing that; so I ask to make sure I'm not doing all this work 
in vain.

Thanks, and even though I'm not a very active member at all on this 
list, I want to thank all of you who have helped me with my SDL problems 
in the past, and wish you all a happy new year! =)