Using with statement to handle SharedObject locker.

3 files changed, 87 insertions, 120 deletions

diff --git a/src/argaze/ArFeatures.py b/src/argaze/ArFeatures.py
index ff29baa..1b3e504 100644
--- a/src/argaze/ArFeatures.py
+++ b/src/argaze/ArFeatures.py
@@ -372,11 +372,8 @@ class ArLayer(DataFeatures.SharedObject, DataFeatures.PipelineStepObject):
 			gaze_movement: gaze movement to project
 		"""
 
-		# Use try block to always release the layer lock in finally block
-		try:
-
-			# Lock layer exploitation
-			self.acquire()
+		# Use layer locker feature
+		with self.locker:
 
 			# Update current gaze movement
 			self.__gaze_movement = gaze_movement
@@ -420,11 +417,6 @@ class ArLayer(DataFeatures.SharedObject, DataFeatures.PipelineStepObject):
 					if self.aoi_scan_path is not None:
 
 						self.aoi_scan_path.append_saccade(timestamp, gaze_movement)
-		
-		finally:
-
-			# Unlock layer exploitation
-			self.release()
 
 	def draw(self, image: numpy.array, draw_aoi_scene: dict = None, draw_aoi_matching: dict = None):
 		"""
@@ -440,21 +432,18 @@ class ArLayer(DataFeatures.SharedObject, DataFeatures.PipelineStepObject):
 
 			return self.draw(image, **self.draw_parameters)
 
-		# Lock layer exploitation
-		self.acquire()
-
-		# Draw aoi if required
-		if draw_aoi_scene is not None:
+		# Use layer locker feature
+		with self.locker:
 
-			self.aoi_scene.draw(image, **draw_aoi_scene)
+			# Draw aoi if required
+			if draw_aoi_scene is not None:
 
-		# Draw aoi matching if required
-		if draw_aoi_matching is not None and self.aoi_matcher is not None:
+				self.aoi_scene.draw(image, **draw_aoi_scene)
 
-			self.aoi_matcher.draw(image, self.aoi_scene, **draw_aoi_matching)
+			# Draw aoi matching if required
+			if draw_aoi_matching is not None and self.aoi_matcher is not None:
 
-		# Unlock layer exploitation
-		self.release()
+				self.aoi_matcher.draw(image, self.aoi_scene, **draw_aoi_matching)
 
 # Define default ArFrame image parameters
 DEFAULT_ARFRAME_IMAGE_PARAMETERS = {
@@ -815,11 +804,8 @@ class ArFrame(DataFeatures.SharedObject, DataFeatures.PipelineStepObject):
 			gaze_position: gaze position to project
 		"""
 
-		# Use try block to always release the frame lock in finally block
-		try:
-
-			# Lock frame exploitation
-			self.acquire()
+		# Use frame locker feature
+		with self.locker:
 
 			# No gaze movement identified by default
 			self.__identified_gaze_movement = GazeFeatures.UnvalidGazeMovement()
@@ -891,11 +877,6 @@ class ArFrame(DataFeatures.SharedObject, DataFeatures.PipelineStepObject):
 
 				layer.look(timestamp, self.__identified_gaze_movement)
 
-		finally:
-
-			# Unlock frame exploitation
-			self.release()
-
 	def __image(self, background_weight: float = None, heatmap_weight: float = None, draw_gaze_position_calibrator: dict = None, draw_scan_path: dict = None, draw_layers: dict = None, draw_gaze_positions: dict = None, draw_fixations: dict = None, draw_saccades: dict = None) -> numpy.array:
 		"""
 		Get background image with overlaid visualisations.
@@ -911,65 +892,62 @@ class ArFrame(DataFeatures.SharedObject, DataFeatures.PipelineStepObject):
 			draw_saccades: [GazeFeatures.Saccade.draw](argaze.md/#argaze.GazeFeatures.Saccade.draw) parameters (if None, no saccade is drawn)
 		"""
 
-		# Lock frame exploitation
-		self.acquire()
+		# Use frame locker feature
+		with self.locker:
 
-		# Draw background only
-		if background_weight is not None and (heatmap_weight is None or self.heatmap is None):
+			# Draw background only
+			if background_weight is not None and (heatmap_weight is None or self.heatmap is None):
 
-			image = self.background.copy()
+				image = self.background.copy()
 
-		# Draw mix background and heatmap if required
-		elif background_weight  is not None and heatmap_weight  is not None and self.heatmap:
+			# Draw mix background and heatmap if required
+			elif background_weight  is not None and heatmap_weight  is not None and self.heatmap:
 
-			background_image = self.background.copy()
-			heatmap_image = cv2.resize(self.heatmap.image, dsize=self.size, interpolation=cv2.INTER_LINEAR)
-			image = cv2.addWeighted(heatmap_image, heatmap_weight, background_image, background_weight, 0)
+				background_image = self.background.copy()
+				heatmap_image = cv2.resize(self.heatmap.image, dsize=self.size, interpolation=cv2.INTER_LINEAR)
+				image = cv2.addWeighted(heatmap_image, heatmap_weight, background_image, background_weight, 0)
 
-		# Draw heatmap only
-		elif background_weight is None and heatmap_weight is not None and self.heatmap:
+			# Draw heatmap only
+			elif background_weight is None and heatmap_weight is not None and self.heatmap:
 
-			image = cv2.resize(self.heatmap.image, dsize=self.size, interpolation=cv2.INTER_LINEAR)
+				image = cv2.resize(self.heatmap.image, dsize=self.size, interpolation=cv2.INTER_LINEAR)
 
-		# Draw black image
-		else:
-
-			image = numpy.full((self.size[1], self.size[0], 3), 0).astype(numpy.uint8)
+			# Draw black image
+			else:
 
-		# Draw gaze position calibrator
-		if draw_gaze_position_calibrator is not None:
+				image = numpy.full((self.size[1], self.size[0], 3), 0).astype(numpy.uint8)
 
-			self.gaze_position_calibrator.draw(image, size=self.size, **draw_gaze_position_calibrator)
+			# Draw gaze position calibrator
+			if draw_gaze_position_calibrator is not None:
 
-		# Draw scan path if required
-		if draw_scan_path is not None and self.scan_path is not None:
+				self.gaze_position_calibrator.draw(image, size=self.size, **draw_gaze_position_calibrator)
 
-			self.scan_path.draw(image, **draw_scan_path)
+			# Draw scan path if required
+			if draw_scan_path is not None and self.scan_path is not None:
 
-		# Draw current fixation if required
-		if draw_fixations is not None and self.gaze_movement_identifier is not None:
+				self.scan_path.draw(image, **draw_scan_path)
 
-			self.gaze_movement_identifier.current_fixation.draw(image, **draw_fixations)
+			# Draw current fixation if required
+			if draw_fixations is not None and self.gaze_movement_identifier is not None:
 
-		# Draw current saccade if required
-		if draw_saccades is not None and self.gaze_movement_identifier is not None:
+				self.gaze_movement_identifier.current_fixation.draw(image, **draw_fixations)
 
-			self.gaze_movement_identifier.current_saccade.draw(image, **draw_saccades)
+			# Draw current saccade if required
+			if draw_saccades is not None and self.gaze_movement_identifier is not None:
 
-		# Draw layers if required
-		if draw_layers is not None:
+				self.gaze_movement_identifier.current_saccade.draw(image, **draw_saccades)
 
-			for layer_name, draw_layer in draw_layers.items():
+			# Draw layers if required
+			if draw_layers is not None:
 
-				self.layers[layer_name].draw(image, **draw_layer)
+				for layer_name, draw_layer in draw_layers.items():
 
-		# Draw current gaze position if required
-		if draw_gaze_positions is not None:
+					self.layers[layer_name].draw(image, **draw_layer)
 
-			self.__calibrated_gaze_position.draw(image, **draw_gaze_positions)
+			# Draw current gaze position if required
+			if draw_gaze_positions is not None:
 
-		# Unlock frame exploitation
-		self.release()
+				self.__calibrated_gaze_position.draw(image, **draw_gaze_positions)
 
 		return image
 
@@ -1370,11 +1348,8 @@ class ArCamera(ArFrame):
 		# Project gaze position into camera frame
 		super().look(timestamp, gaze_position)
 
-		# Use try block to always release the camera frame lock in finally block
-		try:
-
-			# Lock camera frame exploitation
-			self.acquire()
+		# Use camera frame locker feature
+		with self.locker:
 
 			# Project gaze position into each scene frames if possible
 			for scene_frame in self.scene_frames:
@@ -1402,11 +1377,6 @@ class ArCamera(ArFrame):
 
 						pass
 
-		finally:
-
-			# Unlock camera frame exploitation
-			self.release()
-
 	def map(self):
 		"""Project camera frame background into scene frames background.
 
@@ -1414,32 +1384,29 @@ class ArCamera(ArFrame):
 			watch method needs to be called first.
 		"""
 
-		# Lock camera frame exploitation
-		self.acquire()
-
-		# Project camera frame background into each scene frame if possible
-		for frame in self.scene_frames:
+		# Use camera frame locker feature
+		with self.locker:
 
-			# Is there an AOI inside camera frame layers projection which its name equals to a scene frame name?
-			for camera_layer_name, camera_layer in self.layers.items():
+			# Project camera frame background into each scene frame if possible
+			for frame in self.scene_frames:
 
-				try:
+				# Is there an AOI inside camera frame layers projection which its name equals to a scene frame name?
+				for camera_layer_name, camera_layer in self.layers.items():
 
-					aoi_2d = camera_layer.aoi_scene[frame.name]
+					try:
 
-					# Apply perspective transform algorithm to fill aoi frame background
-					width, height = frame.size
-					destination = numpy.float32([[0, 0], [width, 0], [width, height], [0, height]])
-					mapping = cv2.getPerspectiveTransform(aoi_2d.astype(numpy.float32), destination)
-					frame.background = cv2.warpPerspective(self.background, mapping, (width, height))
+						aoi_2d = camera_layer.aoi_scene[frame.name]
 
-				# Ignore missing frame projection
-				except KeyError:
+						# Apply perspective transform algorithm to fill aoi frame background
+						width, height = frame.size
+						destination = numpy.float32([[0, 0], [width, 0], [width, height], [0, height]])
+						mapping = cv2.getPerspectiveTransform(aoi_2d.astype(numpy.float32), destination)
+						frame.background = cv2.warpPerspective(self.background, mapping, (width, height))
 
-					pass
+					# Ignore missing frame projection
+					except KeyError:
 
-		# Unlock camera frame exploitation
-		self.release()
+						pass
 
 	def to_json(self, json_filepath):
 		"""Save camera to .json file."""
diff --git a/src/argaze/ArUcoMarkers/ArUcoCamera.py b/src/argaze/ArUcoMarkers/ArUcoCamera.py
index dcabd81..916c9ed 100644
--- a/src/argaze/ArUcoMarkers/ArUcoCamera.py
+++ b/src/argaze/ArUcoMarkers/ArUcoCamera.py
@@ -150,11 +150,8 @@ class ArUcoCamera(ArFeatures.ArCamera):
 			This method timestamps camera frame and its layers.
 		"""
 
-		# Use try block to always release the camera frame lock in finally block
-		try:
-
-			# Lock camera frame exploitation
-			self.acquire()
+		# Use camera frame locker feature
+		with self.locker:
 
 			# Detect aruco markers
 			self.aruco_detector.detect_markers(image)
@@ -201,13 +198,8 @@ class ArUcoCamera(ArFeatures.ArCamera):
 
 						pass
 
-		finally:
-
-			# Unlock camera frame exploitation
-			self.release()
-
-			# Timestamp camera frame
-			self.timestamp = timestamp
+		# Timestamp camera frame
+		self.timestamp = timestamp
 
 	def __image(self, draw_detected_markers: dict = None, draw_scenes: dict = None, draw_optic_parameters_grid: dict = None, **kwargs: dict) -> numpy.array:
 		"""Get frame image with ArUco detection visualisation.
@@ -223,22 +215,25 @@ class ArUcoCamera(ArFeatures.ArCamera):
 		# Note: don't lock/unlock camera frame here as super().image manage it.
 		image = super().image(**kwargs)
 
-		# Draw optic parameters grid if required
-		if draw_optic_parameters_grid is not None:
+		# Use frame locker feature
+		with self.locker:
+
+			# Draw optic parameters grid if required
+			if draw_optic_parameters_grid is not None:
 
-			self.aruco_detector.optic_parameters.draw(image, **draw_optic_parameters_grid)
+				self.aruco_detector.optic_parameters.draw(image, **draw_optic_parameters_grid)
 
-		# Draw scenes if required
-		if draw_scenes is not None:
+			# Draw scenes if required
+			if draw_scenes is not None:
 
-			for scene_name, draw_scenes_parameters in draw_scenes.items():
+				for scene_name, draw_scenes_parameters in draw_scenes.items():
 
-				self.scenes[scene_name].draw(image, **draw_scenes_parameters)
+					self.scenes[scene_name].draw(image, **draw_scenes_parameters)
 
-		# Draw detected markers if required
-		if draw_detected_markers is not None:
+			# Draw detected markers if required
+			if draw_detected_markers is not None:
 
-			self.aruco_detector.draw_detected_markers(image, draw_detected_markers)
+				self.aruco_detector.draw_detected_markers(image, draw_detected_markers)
 
 		return image
 
diff --git a/src/argaze/DataFeatures.py b/src/argaze/DataFeatures.py
index 1e6abfe..4dfd911 100644
--- a/src/argaze/DataFeatures.py
+++ b/src/argaze/DataFeatures.py
@@ -368,12 +368,17 @@ class SharedObject():
         self._execution_times = {}
         self._exceptions = {}
 
+    @property
+    def locker(self) -> threading.Lock:
+        return self._lock
+
     def acquire(self):
         self._lock.acquire()
 
     def release(self):
         self._lock.release()
 
+    @property
     def locked(self) -> bool:
         return self._lock.locked()