http://www.vlfeat.org/overview/sift.html

http://docs.opencv.org/3.0-beta/modules/stitching/doc/introduction.html

http://uk.mathworks.com/help/vision/examples/feature-based-panoramic-image-stitching.html?s_tid=gn_loc_drop

http://web.stanford.edu/class/cs231a/prev_projects/Chau_Karol_CS231a_Final_Paper.pdf