From 00acb984360439d5480bd84d5a212a5524984900 Mon Sep 17 00:00:00 2001
From: Sergey Sharybin
Date: Thu, 27 Feb 2014 14:27:30 +0600
Subject: [PATCH] Fix T38844: Crash if weight track = 0
Avoid zero-sized problem when doing euclidean intersection
Zero-sized problem might occur when intersecting track with
constant zero weight. For such tracks we'll just use result
of algebraic intersection.
TODO: We probably need to have a separate BA step to adjust
positions of tracks with constant zero weight.
---
.../libmv/libmv/simple_pipeline/intersect.cc | 20 +++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/extern/libmv/libmv/simple_pipeline/intersect.cc b/extern/libmv/libmv/simple_pipeline/intersect.cc
index 6a098da272d..ddb713684a4 100644
--- a/extern/libmv/libmv/simple_pipeline/intersect.cc
+++ b/extern/libmv/libmv/simple_pipeline/intersect.cc
@@ -100,6 +100,8 @@ bool EuclideanIntersect(const vector &markers,
ceres::Problem problem;
+ // Add residual blocks to the problem.
+ int num_residuals = 0;
for (int i = 0; i < markers.size(); ++i) {
const Marker &marker = markers[i];
if (marker.weight != 0.0) {
@@ -113,9 +115,27 @@ bool EuclideanIntersect(const vector &markers,
3>(new EuclideanIntersectCostFunctor(marker, camera)),
NULL,
&X(0));
+ num_residuals++;
}
}
+ // TODO(sergey): Once we'll update Ceres to the next version
+ // we wouldn't need this check anymore -- Ceres will deal with
+ // zero-sized problems nicely.
+ LG << "Number of residuals: " << num_residuals;
+ if (!num_residuals) {
+ LG << "Skipping running minimizer with zero residuals";
+
+ // We still add 3D point for the track regardless it was
+ // optimized or not. If track is a constant zero it'll use
+ // algebraic intersection result as a 3D coordinate.
+
+ Vec3 point = X.head<3>();
+ reconstruction->InsertPoint(markers[0].track, point);
+
+ return true;
+ }
+
// Configure the solve.
ceres::Solver::Options solver_options;
solver_options.linear_solver_type = ceres::DENSE_QR;
--
2.26.2