From d3c092431e5d973242ad7a0baeedc0b8ea2c4677 Mon Sep 17 00:00:00 2001
From: Nathan Perkins <nathan@maxmo.net>
Date: Sat, 29 Apr 2017 09:37:04 -0400
Subject: [PATCH] Improve match single to use length constraint

Calculate the threshold for match_single respecting the length constraint. Produces better matches.
---
 find_audio.m | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/find_audio.m b/find_audio.m
index bf3180f..87641fd 100644
--- a/find_audio.m
+++ b/find_audio.m
@@ -251,12 +251,7 @@
         
         % single extraction mode
         if match_single
-            t = sort(scores);
-            if isempty(thresh_score)
-                thresh_score = t(4);
-            else
-                thresh_score = t(thresh_score);
-            end
+            thresh_score = Inf;
         end
 
         % threshold
@@ -286,10 +281,18 @@
         
         if match_single
             % match single... short circuit sliding window logic
-            [~, potential_ends] = min(scores);
+            [s, potential_ends] = min(scores);
+            
+            % no score
+            if isnan(s)
+                potential_ends = [];
+            end
             
             % update start index
-            cor(cor == 0) = 1;
+            if any(cor(potential_ends) == 0)
+                warning('Matches at boundary, may be clipped.');
+                cor(cor == 0) = 1;
+            end
         else        
             % no zero starts
             scores(cor == 0) = nan;