colmap · lpanaf · Feb 20, 2024 · Jun 20, 2024 · Jul 19, 2024 · Nov 28, 2024
diff --git a/src/colmap/controllers/hierarchical_pipeline_test.cc b/src/colmap/controllers/hierarchical_pipeline_test.cc
@@ -102,7 +102,7 @@ TEST(HierarchicalPipeline, WithoutNoiseAndNonTrivialFrames) {
  synthetic_dataset_options.num_rigs = 2;
  synthetic_dataset_options.num_cameras_per_rig = 2;
  synthetic_dataset_options.num_frames_per_rig = 10;
-  synthetic_dataset_options.num_points3D = 100;
+  synthetic_dataset_options.num_points3D = 200;
  synthetic_dataset_options.point2D_stddev = 0;
  SynthesizeDataset(synthetic_dataset_options, &gt_reconstruction, &database);


diff --git a/src/colmap/scene/synthetic.cc b/src/colmap/scene/synthetic.cc
@@ -174,6 +174,7 @@ void SynthesizeDataset(const SyntheticDatasetOptions& options,
  THROW_CHECK_GE(options.num_points3D, 0);
  THROW_CHECK_GE(options.num_points2D_without_point3D, 0);
  THROW_CHECK_GE(options.sensor_from_rig_translation_stddev, 0.);
+  THROW_CHECK_GE(options.sensor_from_rig_rotation_stddev, 0.);
  THROW_CHECK_GE(options.point2D_stddev, 0.);
  THROW_CHECK_GE(options.prior_position_stddev, 0.);

@@ -215,6 +216,17 @@ void SynthesizeDataset(const SyntheticDatasetOptions& options,
        rig.AddRefSensor(camera.SensorId());
      } else {
        Rigid3d sensor_from_rig;
+        if (options.sensor_from_rig_rotation_stddev > 0) {
+          // Generate a random rotation around the Z-axis.
+          // This is to avoid 2D points fall behind the camera.
+          const double angle =
+              std::clamp(RandomGaussian<double>(
+                             0, options.sensor_from_rig_rotation_stddev),
+                         -180.0,
+                         180.0);
+          sensor_from_rig.rotation = Eigen::Quaterniond(
+              Eigen::AngleAxisd(DegToRad(angle), Eigen::Vector3d(0, 0, 1)));
+        }
        if (options.sensor_from_rig_translation_stddev > 0) {
          sensor_from_rig.translation = Eigen::Vector3d(
              RandomGaussian<double>(
@@ -293,6 +305,9 @@ void SynthesizeDataset(const SyntheticDatasetOptions& options,
          Point2D point2D;
          const std::optional<Eigen::Vector2d> proj_point2D =
              camera.ImgFromCam(cam_from_world * point3D.xyz);
+          if (!proj_point2D.has_value()) {
+            continue;  // Point is behind the camera.
+          }
          point2D.xy = proj_point2D.value();
          if (options.point2D_stddev > 0) {
            const Eigen::Vector2d noise(

diff --git a/src/colmap/scene/synthetic.h b/src/colmap/scene/synthetic.h
@@ -43,6 +43,7 @@ struct SyntheticDatasetOptions {
  int num_points3D = 100;

  double sensor_from_rig_translation_stddev = 0.05;
+  double sensor_from_rig_rotation_stddev = 5.;  // in degrees

  int camera_width = 1024;
  int camera_height = 768;