tracker/pt: cv::Mat::at<T> is slow, use cv::Mat::ptr

1 files changed, 2 insertions, 1 deletions

diff --git a/tracker-pt/point_extractor.cpp b/tracker-pt/point_extractor.cpp
index 6eb255a5..6118f3d2 100644
--- a/tracker-pt/point_extractor.cpp
+++ b/tracker-pt/point_extractor.cpp
@@ -74,9 +74,10 @@ std::vector<cv::Vec2f> PointExtractor::extract_points(cv::Mat& frame)
         int cnt = 0;
         constexpr int min_pixels = 250;
         const auto pixels_to_include = std::max<int>(0, min_pixels * s.threshold/100.);
+        auto ptr = reinterpret_cast<const float*>(hist.ptr(0));
         for (int i = sz-1; i >= 0; i--)
         {
-            cnt += hist.at<float>(i);
+            cnt += ptr[i];
             if (cnt >= pixels_to_include)
             {
                 val = i;