Rework 2D stabilizator

See this page for motivation and description of concepts:
https://github.com/Ichthyostega/blender/wiki

See this video for UI explanation and demonstration of usage
http://vimeo.com/blenderHack/stabilizerdemo

This proposal attempts to improve usability of Blender's image stabilization
feature for real-world footage esp. with moving and panning camera. It builds
upon the feature tracking to get a measurement of 2D image movement.

  - Use a weighted average of movement contributions (instead of a median).
  - Allow for rotation compensation and zoom (image scale) compensation.
  - Allow to pick a different set of tracks for translation and for
    rotation/zoom.
  - Treat translation / rotation / zoom contributions systematically in a
    similar way.
  - Improve handling of partial tracking data with gaps and varying
    start / end points.
  - Have a user definable anchor frame and interpolate / extrapolate data to
    avoid jumping back to "neutral" position when no tracking data is available.
  - Support for travelling and panning shots by including an //intended//
    position/rotation/zoom ("target position"). The idea is for these parameters
    to be //animated// by the user, in order to supply an smooth, intended
    camera movement. This way, we can keep the image content roughly in frame
    even when moving completely away from the initial view.

A known shortcoming is that the pivot point for rotation compensation is set to
the translation compensated image center. This can produce spurious rotation on
travelling shots, which needs to be compensated manually (by animating the
target rotation parameter). There are several possible ways to address that
problem, yet all of them are considered beyond the scope of this improvement
proposal for now.

Own modifications:

- Restrict line length, it's really handy for split-view editing
- In motion tracking we prefer fully human-readable comments, meaning we
  don't use doxygen with it's weird markup and comments are supposed to
  start with capital and end with a full stop,
- Add explicit comparison of pointer to NULL.

Reviewers: sergey

Subscribers: kusi, kdawg, forest-house, mardy, Samoth, plasmasolutions, willolis, sebastian_k, hype, enetheru, sunboy, jta, leon_cheung

Maniphest Tasks: T49036

Differential Revision: https://developer.blender.org/D583

1 files changed, 123 insertions, 18 deletions

diff --git a/source/blender/editors/space_clip/tracking_ops_stabilize.c b/source/blender/editors/space_clip/tracking_ops_stabilize.c
index 8d6173e1cea..35b1aead343 100644
--- a/source/blender/editors/space_clip/tracking_ops_stabilize.c
+++ b/source/blender/editors/space_clip/tracking_ops_stabilize.c
@@ -84,7 +84,6 @@ static int stabilize_2d_add_exec(bContext *C, wmOperator *UNUSED(op))
 	}
 
 	if (update) {
-		stab->ok = 0;
 		DAG_id_tag_update(&clip->id, 0);
 		WM_event_add_notifier(C, NC_MOVIECLIP | ND_DISPLAY, clip);
 	}
@@ -96,7 +95,7 @@ void CLIP_OT_stabilize_2d_add(wmOperatorType *ot)
 {
 	/* identifiers */
 	ot->name = "Add Stabilization Tracks";
-	ot->description = "Add selected tracks to 2D stabilization tool";
+	ot->description = "Add selected tracks to 2D translation stabilization";
 	ot->idname = "CLIP_OT_stabilize_2d_add";
 
 	/* api callbacks */
@@ -139,7 +138,6 @@ static int stabilize_2d_remove_exec(bContext *C, wmOperator *UNUSED(op))
 	}
 
 	if (update) {
-		stab->ok = 0;
 		DAG_id_tag_update(&clip->id, 0);
 		WM_event_add_notifier(C, NC_MOVIECLIP | ND_DISPLAY, clip);
 	}
@@ -151,7 +149,7 @@ void CLIP_OT_stabilize_2d_remove(wmOperatorType *ot)
 {
 	/* identifiers */
 	ot->name = "Remove Stabilization Track";
-	ot->description = "Remove selected track from stabilization";
+	ot->description = "Remove selected track from translation stabilization";
 	ot->idname = "CLIP_OT_stabilize_2d_remove";
 
 	/* api callbacks */
@@ -193,7 +191,7 @@ void CLIP_OT_stabilize_2d_select(wmOperatorType *ot)
 {
 	/* identifiers */
 	ot->name = "Select Stabilization Tracks";
-	ot->description = "Select tracks which are used for stabilization";
+	ot->description = "Select tracks which are used for translation stabilization";
 	ot->idname = "CLIP_OT_stabilize_2d_select";
 
 	/* api callbacks */
@@ -204,20 +202,85 @@ void CLIP_OT_stabilize_2d_select(wmOperatorType *ot)
 	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
 
-/***************** set 2d stabilization rotation track operator ****************/
+/********************** add 2d stabilization tracks for rotation operator ****************/
 
-static int stabilize_2d_set_rotation_exec(bContext *C, wmOperator *UNUSED(op))
+static int stabilize_2d_rotation_add_exec(bContext *C, wmOperator *UNUSED(op))
 {
 	SpaceClip *sc = CTX_wm_space_clip(C);
 	MovieClip *clip = ED_space_clip_get_clip(sc);
 	MovieTracking *tracking = &clip->tracking;
-	MovieTrackingTrack *act_track = BKE_tracking_track_get_active(tracking);
+	ListBase *tracksbase = BKE_tracking_get_active_tracks(tracking);
+	MovieTrackingStabilization *stab = &tracking->stabilization;
+
+	bool update = false;
+	for (MovieTrackingTrack *track = tracksbase->first;
+	     track != NULL;
+	     track = track->next)
+	{
+		if (TRACK_VIEW_SELECTED(sc, track) &&
+		    (track->flag & TRACK_USE_2D_STAB_ROT) == 0)
+		{
+			track->flag |= TRACK_USE_2D_STAB_ROT;
+			stab->tot_rot_track++;
+			update = true;
+		}
+	}
+
+	if (update) {
+		DAG_id_tag_update(&clip->id, 0);
+		WM_event_add_notifier(C, NC_MOVIECLIP | ND_DISPLAY, clip);
+	}
+
+	return OPERATOR_FINISHED;
+}
+
+void CLIP_OT_stabilize_2d_rotation_add(wmOperatorType *ot)
+{
+	/* identifiers */
+	ot->name = "Add Stabilization Rotation Tracks";
+	ot->description = "Add selected tracks to 2D rotation stabilization";
+	ot->idname = "CLIP_OT_stabilize_2d_rotation_add";
+
+	/* api callbacks */
+	ot->exec = stabilize_2d_rotation_add_exec;
+	ot->poll = stabilize_2d_poll;
+
+	/* flags */
+	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+}
+
+/********************** remove 2d stabilization tracks for rotation operator *************/
+
+static int stabilize_2d_rotation_remove_exec(bContext *C, wmOperator *UNUSED(op))
+{
+	SpaceClip *sc = CTX_wm_space_clip(C);
+	MovieClip *clip = ED_space_clip_get_clip(sc);
+	MovieTracking *tracking = &clip->tracking;
+	MovieTrackingStabilization *stab = &tracking->stabilization;
+	ListBase *tracksbase = BKE_tracking_get_active_tracks(tracking);
+	int a = 0;
+	bool update = false;
 
-	if (act_track != NULL) {
-		MovieTrackingStabilization *stab = &tracking->stabilization;
-		stab->rot_track = act_track;
-		stab->ok = 0;
+	for (MovieTrackingTrack *track = tracksbase->first;
+	     track != NULL;
+	     track = track->next)
+	{
+		if (track->flag & TRACK_USE_2D_STAB_ROT) {
+			if (a == stab->act_rot_track) {
+				track->flag &= ~TRACK_USE_2D_STAB_ROT;
+				stab->act_rot_track--;
+				stab->tot_rot_track--;
+				if (stab->act_rot_track < 0) {
+					stab->act_rot_track = 0;
+				}
+				update = true;
+				break;
+			}
+			a++;
+		}
+	}
 
+	if (update) {
 		DAG_id_tag_update(&clip->id, 0);
 		WM_event_add_notifier(C, NC_MOVIECLIP | ND_DISPLAY, clip);
 	}
@@ -225,18 +288,60 @@ static int stabilize_2d_set_rotation_exec(bContext *C, wmOperator *UNUSED(op))
 	return OPERATOR_FINISHED;
 }
 
-void CLIP_OT_stabilize_2d_set_rotation(wmOperatorType *ot)
+void CLIP_OT_stabilize_2d_rotation_remove(wmOperatorType *ot)
+{
+	/* identifiers */
+	ot->name = "Remove Stabilization Rotation Track";
+	ot->description = "Remove selected track from rotation stabilization";
+	ot->idname = "CLIP_OT_stabilize_2d_rotation_remove";
+
+	/* api callbacks */
+	ot->exec = stabilize_2d_rotation_remove_exec;
+	ot->poll = stabilize_2d_poll;
+
+	/* flags */
+	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
+}
+
+/********************** select 2d stabilization rotation tracks operator *****************/
+
+static int stabilize_2d_rotation_select_exec(bContext *C, wmOperator *UNUSED(op))
+{
+	SpaceClip *sc = CTX_wm_space_clip(C);
+	MovieClip *clip = ED_space_clip_get_clip(sc);
+	MovieTracking *tracking = &clip->tracking;
+	ListBase *tracksbase = BKE_tracking_get_active_tracks(tracking);
+	bool update = false;
+
+	for (MovieTrackingTrack *track = tracksbase->first;
+	     track != NULL;
+	     track = track->next)
+	{
+		if (track->flag & TRACK_USE_2D_STAB_ROT) {
+			BKE_tracking_track_flag_set(track, TRACK_AREA_ALL, SELECT);
+			update = true;
+		}
+	}
+
+	if (update) {
+		WM_event_add_notifier(C, NC_MOVIECLIP | ND_SELECT, clip);
+	}
+
+	return OPERATOR_FINISHED;
+}
+
+void CLIP_OT_stabilize_2d_rotation_select(wmOperatorType *ot)
 {
 	/* identifiers */
-	ot->name = "Set Rotation Track";
-	ot->description = "Use active track to compensate rotation when "
-	                  "doing 2D stabilization";
-	ot->idname = "CLIP_OT_stabilize_2d_set_rotation";
+	ot->name = "Select Stabilization Rotation Tracks";
+	ot->description = "Select tracks which are used for rotation stabilization";
+	ot->idname = "CLIP_OT_stabilize_2d_rotation_select";
 
 	/* api callbacks */
-	ot->exec = stabilize_2d_set_rotation_exec;
+	ot->exec = stabilize_2d_rotation_select_exec;
 	ot->poll = stabilize_2d_poll;
 
 	/* flags */
 	ot->flag = OPTYPE_REGISTER | OPTYPE_UNDO;
 }
+