SIFT an illustrated tutorial

On the web we found a bunch of things... and sometimes interesting things.

http://www.aishack.in/2010/05/sift-scale-invariant-feature-transform/

Here a point per point study of the SIFT process. (I'm not agree with all the illustration, but the idea is here and could help people to understand the meaning of each process).

1. Constructing a scale space
2. LoG Approximation
3. Finding keypoints
4. Get rid of bad key points
5. Assigning an orientation to the keypoints
6. Generate SIFT features