Support multiple distortion models, including a new division model

This commit makes it so CameraIntrinsics is no longer hardcoded
to use the traditional polynomial radial distortion model. Currently
the distortion code has generic logic which is shared between
different distortion models, but had no other models until now.

This moves everything specific to the polynomial radial distortion
to a subclass PolynomialDistortionCameraIntrinsics(), and adds a
new division distortion model suitable for cameras such as the
GoPro which have much stronger distortion due to their fisheye lens.

This also cleans up the internal API of CameraIntrinsics to make
it easier to understand and reduces old C-style code.

New distortion model is available in the Lens panel of MCE.

- Polynomial is the old well-known model
- Division is the new one which s intended to deal better with huge
  distortion.

Coefficients of this model works independent from each other
and for division model one probably want to have positive values
to have a barrel distortion.

1 files changed, 10 insertions, 51 deletions

diff --git a/source/blender/blenkernel/intern/tracking_solver.c b/source/blender/blenkernel/intern/tracking_solver.c
index 44a4c11ec92..9ab1643aab1 100644
--- a/source/blender/blenkernel/intern/tracking_solver.c
+++ b/source/blender/blenkernel/intern/tracking_solver.c
@@ -66,11 +66,7 @@ typedef struct MovieReconstructContext {
 	bool is_camera;
 	short motion_flag;
 
-	float focal_length;
-	float principal_point[2];
-	float k1, k2, k3;
-
-	int width, height;
+	libmv_CameraIntrinsicsOptions camera_intrinsics_options;
 
 	float reprojection_error;
 
@@ -134,22 +130,11 @@ static void reconstruct_retrieve_libmv_intrinsics(MovieReconstructContext *conte
 	struct libmv_Reconstruction *libmv_reconstruction = context->reconstruction;
 	struct libmv_CameraIntrinsics *libmv_intrinsics = libmv_reconstructionExtractIntrinsics(libmv_reconstruction);
 
-	float aspy = 1.0f / tracking->camera.pixel_aspect;
-
-	double focal_length, principal_x, principal_y, k1, k2, k3;
-	int width, height;
-
-	libmv_cameraIntrinsicsExtract(libmv_intrinsics, &focal_length, &principal_x, &principal_y,
-	                              &k1, &k2, &k3, &width, &height);
-
-	tracking->camera.focal = focal_length;
-
-	tracking->camera.principal[0] = principal_x;
-	tracking->camera.principal[1] = principal_y / (double)aspy;
+	libmv_CameraIntrinsicsOptions camera_intrinsics_options;
+	libmv_cameraIntrinsicsExtractOptions(libmv_intrinsics, &camera_intrinsics_options);
 
-	tracking->camera.k1 = k1;
-	tracking->camera.k2 = k2;
-	tracking->camera.k3 = k3;
+	tracking_trackingCameraFromIntrinscisOptions(tracking,
+	                                             &camera_intrinsics_options);
 }
 
 /* Retrieve reconstructed tracks from libmv to blender.
@@ -369,7 +354,6 @@ MovieReconstructContext *BKE_tracking_reconstruction_context_new(MovieClip *clip
 {
 	MovieTracking *tracking = &clip->tracking;
 	MovieReconstructContext *context = MEM_callocN(sizeof(MovieReconstructContext), "MovieReconstructContext data");
-	MovieTrackingCamera *camera = &tracking->camera;
 	ListBase *tracksbase = BKE_tracking_object_get_tracks(tracking, object);
 	float aspy = 1.0f / tracking->camera.pixel_aspect;
 	int num_tracks = BLI_countlist(tracksbase);
@@ -383,16 +367,9 @@ MovieReconstructContext *BKE_tracking_reconstruction_context_new(MovieClip *clip
 	context->select_keyframes =
 		(tracking->settings.reconstruction_flag & TRACKING_USE_KEYFRAME_SELECTION) != 0;
 
-	context->focal_length = camera->focal;
-	context->principal_point[0] = camera->principal[0];
-	context->principal_point[1] = camera->principal[1] * aspy;
-
-	context->width = width;
-	context->height = height;
-
-	context->k1 = camera->k1;
-	context->k2 = camera->k2;
-	context->k3 = camera->k3;
+	tracking_cameraIntrinscisOptionsFromTracking(tracking,
+                                                 width, height,
+                                                 &context->camera_intrinsics_options);
 
 	context->tracks_map = tracks_map_new(context->object_name, context->is_camera, num_tracks, 0);
 
@@ -461,22 +438,6 @@ static void reconstruct_update_solve_cb(void *customdata, double progress, const
 
 	BLI_snprintf(progressdata->stats_message, progressdata->message_size, "Solving camera | %s", message);
 }
-/* FIll in camera intrinsics structure from reconstruction context. */
-static void camraIntrincicsOptionsFromContext(libmv_CameraIntrinsicsOptions *camera_intrinsics_options,
-                                              MovieReconstructContext *context)
-{
-	camera_intrinsics_options->focal_length = context->focal_length;
-
-	camera_intrinsics_options->principal_point_x = context->principal_point[0];
-	camera_intrinsics_options->principal_point_y = context->principal_point[1];
-
-	camera_intrinsics_options->k1 = context->k1;
-	camera_intrinsics_options->k2 = context->k2;
-	camera_intrinsics_options->k3 = context->k3;
-
-	camera_intrinsics_options->image_width = context->width;
-	camera_intrinsics_options->image_height = context->height;
-}
 
 /* Fill in reconstruction options structure from reconstruction context. */
 static void reconstructionOptionsFromContext(libmv_ReconstructionOptions *reconstruction_options,
@@ -506,7 +467,6 @@ void BKE_tracking_reconstruction_solve(MovieReconstructContext *context, short *
 
 	ReconstructProgressData progressdata;
 
-	libmv_CameraIntrinsicsOptions camera_intrinsics_options;
 	libmv_ReconstructionOptions reconstruction_options;
 
 	progressdata.stop = stop;
@@ -515,18 +475,17 @@ void BKE_tracking_reconstruction_solve(MovieReconstructContext *context, short *
 	progressdata.stats_message = stats_message;
 	progressdata.message_size = message_size;
 
-	camraIntrincicsOptionsFromContext(&camera_intrinsics_options, context);
 	reconstructionOptionsFromContext(&reconstruction_options, context);
 
 	if (context->motion_flag & TRACKING_MOTION_MODAL) {
 		context->reconstruction = libmv_solveModal(context->tracks,
-		                                           &camera_intrinsics_options,
+		                                           &context->camera_intrinsics_options,
 		                                           &reconstruction_options,
 		                                           reconstruct_update_solve_cb, &progressdata);
 	}
 	else {
 		context->reconstruction = libmv_solveReconstruction(context->tracks,
-		                                                    &camera_intrinsics_options,
+		                                                    &context->camera_intrinsics_options,
 		                                                    &reconstruction_options,
 		                                                    reconstruct_update_solve_cb, &progressdata);