I worked on this too a few years ago. There is a massive patent minefield out there, including this algorithm.
We were doing recognition of TV shows where you are holding a cell phone in your hand some distance from the TV. A prototype with this algorithm was okay, but very easily confused especially as the number of items in the database increases. You also end up with a lot less amplitude at that distance from the TV which makes the source messier. In theory phase shouldn't have had an effect, but in practise it did so things had to be run multiple times at different offsets to improve matching.
Our final algorithm was way better. It was based on what audio codecs do. It even worked reliably with a 60db signal while there was a 70db interferer signal!
We were doing recognition of TV shows where you are holding a cell phone in your hand some distance from the TV. A prototype with this algorithm was okay, but very easily confused especially as the number of items in the database increases. You also end up with a lot less amplitude at that distance from the TV which makes the source messier. In theory phase shouldn't have had an effect, but in practise it did so things had to be run multiple times at different offsets to improve matching.
Our final algorithm was way better. It was based on what audio codecs do. It even worked reliably with a 60db signal while there was a 70db interferer signal!