make test tolerate to rounding error

modules/ts/src/cuda_test.cpp

@@ -519,13 +519,35 @@ namespace cvtest
 
         int validCount = 0;
 
-        for (size_t i = 0; i < gold.size(); ++i)
+        if (actual.size() == gold.size())
         {
-            const cv::KeyPoint& p1 = gold[i];
-            const cv::KeyPoint& p2 = actual[i];
+            for (size_t i = 0; i < gold.size(); ++i)
+            {
+                const cv::KeyPoint& p1 = gold[i];
+                const cv::KeyPoint& p2 = actual[i];
 
-            if (keyPointsEquals(p1, p2))
-                ++validCount;
+                if (keyPointsEquals(p1, p2))
+                    ++validCount;
+            }
+        }
+        else
+        {
+            std::vector<cv::KeyPoint>& shorter = gold;
+            std::vector<cv::KeyPoint>& longer = actual;
+            if (actual.size() < gold.size())
+            {
+                shorter = actual;
+                longer = gold;
+            }
+            for (size_t i = 0; i < shorter.size(); ++i)
+            {
+                const cv::KeyPoint& p1 = shorter[i];
+                const cv::KeyPoint& p2 = longer[i];
+                const cv::KeyPoint& p3 = longer[i+1];
+
+                if (keyPointsEquals(p1, p2) || keyPointsEquals(p1, p3))
+                    ++validCount;
+            }
         }
 
         return validCount;