HEngine

Prototype of HEngine concept described by Alex X. Liu, Ke Shen, Eric Torng in their paper "Large Scale Hamming Distance Query Processing" ICDE Conference, pages 553 - 564, 2011.

It is a solution of Hamming distance range query problem in a large scale set.

Is supposed to handle only 64 bit binary strings.

tests$ ./matches 7 data/db/table.txt data/query/face2.txt
Reading the dataset ........ done. 752420 db hashes and 343 query hashes.
Building with 7 hamming distance bound ....... done.

Building time: 13.772 seconds

Searching HEngine matches .......
found 100 total matches. Query time: 0.1 seconds

Searching linear matches .......
found 100 total matches. Linear query time: 7.104 seconds

As you can see it is much more faster than linear scanning.