Note: this isn't Efros & Freeman's code, just my implementation of it.
Caveats:
For now, the code only works on grayscale images.
Extending it to color is straightforward. The minimum error cut is
not yet implemented, but is on my list of things to do.
In matlab, by Cheng Li: http://www.mathworks.com/matlabcentral/fileexchange/35828
In matlab, by Christopher de Coro: http://www.cs.princeton.edu/~cdecoro/imagequilting/
In C#, by Robert Burke: http://www.cs.princeton.edu/~cdecoro/imagequilting/
In C#, by Siggharth Jain: http://www.codeproject.com/Articles/24172/Texture-Transfer-using-Efros-Freeman-s-Image-Quilt
In matlab, by Alex Rubinsteyn: http://rubinsteyn.com/comp_photo/texture/
(send me links, I'll add them.)