Port essential and fundamental matrix (cvg#9)

* endpoints triangulation as an option. port output folder.

* fix depth-based scoring for endpoints triangulation.

* bind essential and fundamental matrix.

Author: B1ueber2y

limap/triangulation/bindings.cc

@@ -21,6 +21,8 @@ void bind_functions(py::module &m) {
 
     m.def("get_normal_direction", &getNormalDirection);
     m.def("get_direction_from_VP", &getDirectionFromVP);
+    m.def("compute_essential_matrix", &compute_essential_matrix);
+    m.def("compute_fundamental_matrix", &compute_fundamental_matrix);
     m.def("compute_epipolar_IoU", &compute_epipolar_IoU);
     m.def("triangulate_endpoints", &triangulate_endpoints);
     m.def("triangulate", &triangulate);

limap/triangulation/functions.cc

@@ -39,14 +39,10 @@ V3D getDirectionFromVP(const V3D& vp, const CameraView& view) {
     return direc.normalized();
 }
 
-double compute_epipolar_IoU(const Line2d& l1, const CameraView& view1,
-                            const Line2d& l2, const CameraView& view2) 
+M3D compute_essential_matrix(const CameraView& view1, const CameraView& view2) 
 {
-    const M3D K1_inv = view1.K_inv();
     const M3D R1 = view1.R();
     const V3D T1 = view1.T();
-
-    const M3D K2_inv = view2.K_inv();
     const M3D R2 = view2.R();
     const V3D T2 = view2.T();
 
@@ -60,7 +56,21 @@ double compute_epipolar_IoU(const Line2d& l1, const CameraView& view1,
     tskew(1, 0) = relT[2]; tskew(1, 1) = 0.0; tskew(1, 2) = -relT[0];
     tskew(2, 0) = -relT[1]; tskew(2, 1) = relT[0]; tskew(2, 2) = 0.0;
     M3D E = tskew * relR;
-    M3D F = K2_inv.transpose() * E * K1_inv;
+    return E;
+}
+
+M3D compute_fundamental_matrix(const CameraView& view1, const CameraView& view2) 
+{
+    M3D E = compute_essential_matrix(view1, view2);
+    M3D F = view2.K_inv().transpose() * E * view1.K_inv();
+    return F;
+}
+
+double compute_epipolar_IoU(const Line2d& l1, const CameraView& view1,
+                            const Line2d& l2, const CameraView& view2) 
+{
+    // fundamental matrix
+    M3D F = compute_fundamental_matrix(view1, view2);
 
     // epipolar lines
     V3D coor_l2 = l2.coords();

limap/triangulation/functions.h

@@ -17,6 +17,9 @@ V3D getNormalDirection(const Line2d& l, const CameraView& view);
 V3D getDirectionFromVP(const V3D& vp, const CameraView& view);
 
 // weak epipolar constraints
+M3D compute_essential_matrix(const CameraView& view1, const CameraView& view2);
+M3D compute_fundamental_matrix(const CameraView& view1, const CameraView& view2);
+
 // intersect epipolar lines with the matched line on image 2
 double compute_epipolar_IoU(const Line2d& l1, const CameraView& view1,
                             const Line2d& l2, const CameraView& view2);

limap/triangulation/triangulation.py

@@ -8,6 +8,12 @@ def get_normal_direction(l, view):
 def get_direction_from_VP(vp, view):
     return _tri.get_direction_from_VP(vp, view)
 
+def compute_essential_matrix(view1, view2):
+    return _tri.compute_essential_matrix(view1, view2)
+
+def compute_fundamental_matrix(view1, view2):
+    return _tri.compute_fundamental_matrix(view1, view2)
+
 def compute_epipolar_IoU(l1, view1, l2, view2):
     return _tri.compute_epipolar_IoU(l1, view1, l2, view2)