Searching an Image Database Using SIFT

Question

Several questions have been asked about the SIFT algorithm, but they all seem focussed on a simple comparison between two images. Instead of determining how similar two images a

Answer 1

There are several approaches.

One popular approach is the so called bag of words representation which does matching based solely upon how many descriptors match, thus ignoring the location part consisting of (x, y, scale, and orientation) and just look at the descriptor.

Efficient querying of a large database may use approximate methods like locality sensitive hashing

Other methods may involve vocabulary trees or other data structures.

For an efficient method that also takes into account location information, check out pyramid match kernels