From 88e9a072eccf894172f38903cab2cae6073ea7aa Mon Sep 17 00:00:00 2001
From: Andrey Kamaev <andrey.kamaev@itseez.com>
Date: Mon, 15 Oct 2012 20:46:39 +0400
Subject: [PATCH] Fix binary compatibility of opencv_flann

---
 modules/flann/include/opencv2/flann/dist.h  | 35 +++++++++++++++++++++
 modules/flann/include/opencv2/flann/timer.h | 10 +++---
 modules/flann/src/miniflann.cpp             |  2 +-
 3 files changed, 41 insertions(+), 6 deletions(-)

diff --git a/modules/flann/include/opencv2/flann/dist.h b/modules/flann/include/opencv2/flann/dist.h
index 04fb1ea0a..1800c4f66 100644
--- a/modules/flann/include/opencv2/flann/dist.h
+++ b/modules/flann/include/opencv2/flann/dist.h
@@ -380,6 +380,41 @@ struct HammingLUT
     typedef unsigned char ElementType;
     typedef int ResultType;
 
+    /** this will count the bits in a ^ b
+     */
+    ResultType operator()(const unsigned char* a, const unsigned char* b, int size) const
+    {
+        static const uchar popCountTable[] = 
+        {
+            0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5,
+            1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+            1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+            2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+            1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6,
+            2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+            2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7,
+            3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8
+        };
+        ResultType result = 0;
+        for (int i = 0; i < size; i++) {
+            result += popCountTable[a[i] ^ b[i]];
+        }
+        return result;
+    }
+};
+
+/**
+ * Hamming distance functor - counts the bit differences between two strings - useful for the Brief descriptor
+ * bit count of A exclusive XOR'ed with B
+ */
+struct HammingLUT2
+{
+    typedef False is_kdtree_distance;
+    typedef False is_vector_space_distance;
+
+    typedef unsigned char ElementType;
+    typedef int ResultType;
+
     /** this will count the bits in a ^ b
      */
     ResultType operator()(const unsigned char* a, const unsigned char* b, size_t size) const
diff --git a/modules/flann/include/opencv2/flann/timer.h b/modules/flann/include/opencv2/flann/timer.h
index 6428b0a0d..107371ecd 100644
--- a/modules/flann/include/opencv2/flann/timer.h
+++ b/modules/flann/include/opencv2/flann/timer.h
@@ -32,7 +32,7 @@
 #define OPENCV_FLANN_TIMER_H
 
 #include <time.h>
-#include "opencv2/core/core.hpp"
+
 
 namespace cvflann
 {
@@ -44,7 +44,7 @@ namespace cvflann
  */
 class StartStopTimer
 {
-    int64 startTime;
+    clock_t startTime;
 
 public:
     /**
@@ -66,7 +66,7 @@ public:
      */
     void start()
     {
-        startTime = cv::getTickCount();
+        startTime = clock();
     }
 
     /**
@@ -74,8 +74,8 @@ public:
      */
     void stop()
     {
-        int64 stopTime = cv::getTickCount();
-        value += ( (double)stopTime - startTime) / cv::getTickFrequency();
+        clock_t stopTime = clock();
+        value += ( (double)stopTime - startTime) / CLOCKS_PER_SEC;
     }
 
     /**
diff --git a/modules/flann/src/miniflann.cpp b/modules/flann/src/miniflann.cpp
index d8ae2b07c..0a5d47b0c 100644
--- a/modules/flann/src/miniflann.cpp
+++ b/modules/flann/src/miniflann.cpp
@@ -331,7 +331,7 @@ buildIndex(void*& index, const Mat& data, const IndexParams& params, const Dista
 #if CV_NEON
 typedef ::cvflann::Hamming<uchar> HammingDistance;
 #else
-typedef ::cvflann::HammingLUT HammingDistance;
+typedef ::cvflann::HammingLUT2 HammingDistance;
 #endif
 
 Index::Index()