From b6e9ed4ec5843a5a0cbc170f18e1cf0c8abc18e0 Mon Sep 17 00:00:00 2001
From: Alexey Spizhevoy <no@email>
Date: Tue, 16 Aug 2011 09:51:54 +0000
Subject: [PATCH] fixed bug in opencv_stitching (added handling of homography
 evaluation failure)

---
 modules/stitching/main.cpp     | 1 +
 modules/stitching/matchers.cpp | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/modules/stitching/main.cpp b/modules/stitching/main.cpp
index ea4b331..d465229 100644
--- a/modules/stitching/main.cpp
+++ b/modules/stitching/main.cpp
@@ -549,6 +549,7 @@ int main(int argc, char* argv[])
                     sz.width = cvRound(full_img_sizes[i].width * compose_scale);
                     sz.height = cvRound(full_img_sizes[i].height * compose_scale);
                 }
+
                 Rect roi = warper->warpRoi(sz, static_cast<float>(cameras[i].focal), cameras[i].R);
                 corners[i] = roi.tl();
                 sizes[i] = roi.size();
diff --git a/modules/stitching/matchers.cpp b/modules/stitching/matchers.cpp
index b043886..6365c2b 100644
--- a/modules/stitching/matchers.cpp
+++ b/modules/stitching/matchers.cpp
@@ -465,6 +465,8 @@ void BestOf2NearestMatcher::match(const ImageFeatures &features1, const ImageFea
 
     // Find pair-wise motion
     matches_info.H = findHomography(src_points, dst_points, matches_info.inliers_mask, CV_RANSAC);
+    if (abs(determinant(matches_info.H)) < numeric_limits<double>::epsilon())
+        return;
 
     // Find number of inliers
     matches_info.num_inliers = 0;
-- 
2.7.4