24. The system of claim 14 , wherein the feature retrieval unit sorts a plurality of output electronic documents based on a number of feature points in each document, ranks the plurality of output electronic documents using a first geometric constraint to produce a first ranking, ranks the plurality of output electronic documents using a second geometric constraint to produce a second ranking, reconciles the first ranking with the second ranking to generate a third ranking, and selects information corresponding to an electronic document having a highest rank in the third ranking.
24. The system of claim 14 , wherein the feature retrieval unit sorts a plurality of output electronic documents based on a number of feature points in each document, ranks the plurality of output electronic documents using a first geometric constraint to produce a first ranking, ranks the plurality of output electronic documents using a second geometric constraint to produce a second ranking, reconciles the first ranking with the second ranking to generate a third ranking, and selects information corresponding to an electronic document having a highest rank in the third ranking. 26. The method of claim 24 , wherein the feature retrieval unit uses feature detection with geometric constraints to rank the plurality of output electronic documents using the first geometric constraint to produce the first ranking.