Added support of vertical straightening into stitching

modules/stitching/include/opencv2/stitching/detail/motion_estimators.hpp

@@ -170,7 +170,13 @@ private:
 };
 
 
-void CV_EXPORTS waveCorrect(std::vector<Mat> &rmats);
+enum CV_EXPORTS WaveCorrectKind
+{
+    WAVE_CORRECT_HORIZ,
+    WAVE_CORRECT_VERT
+};
+
+void CV_EXPORTS waveCorrect(std::vector<Mat> &rmats, WaveCorrectKind kind);
 
 
 //////////////////////////////////////////////////////////////////////////////

modules/stitching/include/opencv2/stitching/detail/seam_finders.hpp

@@ -100,6 +100,7 @@ public:
               std::vector<Mat> &masks);
 
 private:
+    // To avoid GCGraph dependency
     class Impl;
     Ptr<Impl> impl_;
 };

modules/stitching/include/opencv2/stitching/detail/warpers.hpp

@@ -129,6 +129,7 @@ protected:
     void detectResultRoi(Point &dst_tl, Point &dst_br);
 };
 
+
 #ifndef ANDROID
 class CV_EXPORTS PlaneWarperGpu : public PlaneWarper
 {

modules/stitching/include/opencv2/stitching/stitcher.hpp

@@ -96,6 +96,9 @@ public:
     void setBundleAdjuster(Ptr<detail::BundleAdjusterBase> bundle_adjuster)
         { bundle_adjuster_ = bundle_adjuster; }
 
+    detail::WaveCorrectKind waveCorrectKind() const { return wave_correct_kind_; }
+    void setWaveCorrectKind(detail::WaveCorrectKind kind) { wave_correct_kind_ = kind; }
+
     Ptr<WarperCreator> warper() { return warper_; }
     const Ptr<WarperCreator> warper() const { return warper_; }
     void setWarper(Ptr<WarperCreator> warper) { warper_ = warper; }
@@ -124,6 +127,7 @@ private:
     Ptr<detail::FeaturesFinder> features_finder_;
     Ptr<detail::FeaturesMatcher> features_matcher_;
     Ptr<detail::BundleAdjusterBase> bundle_adjuster_;
+    detail::WaveCorrectKind wave_correct_kind_;
     Ptr<WarperCreator> warper_;
     Ptr<detail::ExposureCompensator> exposure_comp_;
     Ptr<detail::SeamFinder> seam_finder_;

modules/stitching/src/motion_estimators.cpp

@@ -567,7 +567,7 @@ void BundleAdjusterRay::calcJacobian(Mat &jac)
 
 //////////////////////////////////////////////////////////////////////////////
 
-void waveCorrect(vector<Mat> &rmats)
+void waveCorrect(vector<Mat> &rmats, WaveCorrectKind kind)
 {
     LOGLN("Wave correcting...");
     int64 t = getTickCount();
@@ -580,7 +580,14 @@ void waveCorrect(vector<Mat> &rmats)
     }
     Mat eigen_vals, eigen_vecs;
     eigen(moment, eigen_vals, eigen_vecs);
-    Mat rg1 = eigen_vecs.row(2).t();
+
+    Mat rg1;
+    if (kind == WAVE_CORRECT_HORIZ)
+        rg1 = eigen_vecs.row(2).t();
+    else if (kind == WAVE_CORRECT_VERT)
+        rg1 = eigen_vecs.row(0).t();
+    else
+        CV_Error(CV_StsBadArg, "unsupported kind of wave correction");
 
     Mat img_k = Mat::zeros(3, 1, CV_32F);
     for (size_t i = 0; i < rmats.size(); ++i)
@@ -590,6 +597,29 @@ void waveCorrect(vector<Mat> &rmats)
 
     Mat rg2 = rg0.cross(rg1);
 
+    double conf = 0;
+    if (kind == WAVE_CORRECT_HORIZ)
+    {
+        for (size_t i = 0; i < rmats.size(); ++i)
+            conf += rg0.dot(rmats[i].col(0));
+        if (conf < 0)
+        {
+            rg0 *= -1;
+            rg1 *= -1;
+        }
+    }
+    else if (kind == WAVE_CORRECT_VERT)
+    {
+        for (size_t i = 0; i < rmats.size(); ++i)
+            conf -= rg1.dot(rmats[i].col(0));
+        cout << conf << endl;
+        if (conf < 0)
+        {
+            rg0 *= -1;
+            rg1 *= -1;
+        }
+    }
+
     Mat R = Mat::zeros(3, 3, CV_32F);
     Mat tmp = R.row(0);
     Mat(rg0.t()).copyTo(tmp);

modules/stitching/src/stitcher.cpp

@@ -56,6 +56,7 @@ Stitcher Stitcher::createDefault(bool try_use_gpu)
     stitcher.setHorizontalStrightening(true);
     stitcher.setFeaturesMatcher(new detail::BestOf2NearestMatcher(try_use_gpu));
     stitcher.setBundleAdjuster(new detail::BundleAdjusterRay());
+    stitcher.setWaveCorrectKind(detail::WAVE_CORRECT_HORIZ);
 
 #ifndef ANDROID
     if (try_use_gpu && gpu::getCudaEnabledDeviceCount() > 0)
@@ -208,7 +209,7 @@ Stitcher::Status Stitcher::stitch(InputArray imgs_, OutputArray pano_)
         vector<Mat> rmats;
         for (size_t i = 0; i < cameras.size(); ++i)
             rmats.push_back(cameras[i].R);
-        detail::waveCorrect(rmats);
+        detail::waveCorrect(rmats, wave_correct_kind_);
         for (size_t i = 0; i < cameras.size(); ++i)
             cameras[i].R = rmats[i];
     }