Scale Invariant Feature Transformation
SIFTing through the images!
The SIFT algorithm takes an image and transforms it into a collection of local feature vectors. Each of these feature vectors is distinctive and invariant to any scaling, rotation or translation of the image. They are also robust with respect to noise, occlusion, some forms of affine distortion and illumination changes. The features are relatively easy to extract and are also robust to partial occlusion.