For a special project, I need to find an API/DLL/Library to help me create a big image using parts of this image. For example, if someone take 4 pictures representing the 36
As far as i know Hugin is best which comes with source for both mac and windows
http://hugin.sourceforge.net/
It's using one of the best stitching algorithm which many industry big names in this field use it
Also Take a look at GIMP
and pano12 from panotools which is core of ptstitcher
And
For preview your pano files use devalvr
http://www.devalvr.com/
u can extract installer and use ocx within installer it's fastest for stand-alone projects with many parameters , commands , methods , etc