Removing use of marker size. Enabling context management for PipelineStepObject.

4 files changed, 58 insertions, 31 deletions

diff --git a/src/argaze/ArFeatures.py b/src/argaze/ArFeatures.py
index 0062c53..5951c95 100644
--- a/src/argaze/ArFeatures.py
+++ b/src/argaze/ArFeatures.py
@@ -163,7 +163,7 @@ class ArLayer(DataFeatures.SharedObject, DataFeatures.PipelineStepObject):
 		for name, analyzer in self.__aoi_scan_path_analyzers.items():
 
 			analyzer.parent = self
-	
+
 	@property
 	def aoi_scene(self) -> AOIFeatures.AOIScene:
 		"""Get layer's aoi scene object."""
@@ -574,7 +574,7 @@ class ArFrame(DataFeatures.SharedObject, DataFeatures.PipelineStepObject):
 		for name, layer in self.__layers.items():
 
 			layer.parent = self
-	
+
 	@property
 	def size(self) -> tuple[int]:
 		"""Get frame's size."""
@@ -1111,7 +1111,7 @@ class ArScene(DataFeatures.PipelineStepObject):
 		for name, frame in self.__frames.items():
 
 			frame.parent = self
-	
+
 	@property
 	def layers(self) -> dict:
 		"""Get scene's layers dictionary."""
diff --git a/src/argaze/ArUcoMarkers/ArUcoDetector.py b/src/argaze/ArUcoMarkers/ArUcoDetector.py
index d326aaa..8c843ae 100644
--- a/src/argaze/ArUcoMarkers/ArUcoDetector.py
+++ b/src/argaze/ArUcoMarkers/ArUcoDetector.py
@@ -131,21 +131,13 @@ class DetectorParameters():
         return self.__parameters
 
 class ArUcoDetector(DataFeatures.PipelineStepObject):
-    """ArUco markers detector.
+    """OpenCV ArUco library wrapper."""
 
-    Parameters:
-        dictionary: ArUco markers dictionary to detect.
-        marker_size: Size of ArUco markers to detect in centimeter.
-        optic_parameters: Optic parameters to use for ArUco detection into image.
-        parameters: ArUco detector parameters.
-    """
-
-    def __init__(self, dictionary: ArUcoMarkersDictionary.ArUcoMarkersDictionary = None, marker_size: float = 0., optic_parameters: ArUcoOpticCalibrator.OpticParameters = None, parameters: DetectorParameters = None):
-        """ Initialize ArUcoDetector.
+    def __init__(self, dictionary: ArUcoMarkersDictionary.ArUcoMarkersDictionary = None, optic_parameters: ArUcoOpticCalibrator.OpticParameters = None, parameters: DetectorParameters = None):
+        """Initialize ArUcoDetector.
 
         Parameters:
             dictionary: ArUco markers dictionary to detect.
-            marker_size: Size of ArUco markers to detect in centimeter.
             optic_parameters: Optic parameters to use for ArUco detection into image.
             parameters: ArUco detector parameters.
         """
@@ -155,7 +147,6 @@ class ArUcoDetector(DataFeatures.PipelineStepObject):
 
         # Init private attributes
         self.__dictionary = dictionary
-        self.__marker_size = marker_size
         self.__optic_parameters = optic_parameters
         self.__parameters = parameters
 
@@ -178,11 +169,6 @@ class ArUcoDetector(DataFeatures.PipelineStepObject):
         return self.__dictionary
     
     @property
-    def marker_size(self) -> float:
-        """Get aruco detector's marker size."""
-        return self.__marker_size
-    
-    @property
     def optic_parameters(self) -> ArUcoOpticCalibrator.OpticParameters:
         """Get aruco detector's opetic parameters object."""
         return self.__optic_parameters
@@ -224,9 +210,6 @@ class ArUcoDetector(DataFeatures.PipelineStepObject):
 
             new_dictionary = ArUcoMarkersDictionary.ArUcoMarkersDictionary(**dictionary_value)
 
-        # Load ArUco marker size
-        new_marker_size = aruco_detector_data.pop('marker_size')
-
         # Load optic parameters
         try:
             optic_parameters_value = aruco_detector_data.pop('optic_parameters')
@@ -268,7 +251,7 @@ class ArUcoDetector(DataFeatures.PipelineStepObject):
             new_parameters = DetectorParameters()
 
         # Create aruco detector
-        return ArUcoDetector(new_dictionary, new_marker_size, new_optic_parameters, new_parameters)
+        return ArUcoDetector(new_dictionary, new_optic_parameters, new_parameters)
 
     @classmethod
     def from_json(self, json_filepath: str) -> ArUcoDetectorType:
@@ -323,7 +306,7 @@ class ArUcoDetector(DataFeatures.PipelineStepObject):
 
             for i, marker_id in enumerate(detected_markers_ids):
 
-                marker = ArUcoMarker.ArUcoMarker(self.__dictionary, marker_id, self.__marker_size)
+                marker = ArUcoMarker.ArUcoMarker(self.__dictionary, marker_id)
                 marker.corners = detected_markers_corners[i][0]
 
                 # No pose estimation: call estimate_markers_pose to get one
diff --git a/src/argaze/ArUcoMarkers/ArUcoMarker.py b/src/argaze/ArUcoMarkers/ArUcoMarker.py
index 0f368f6..b626ea4 100644
--- a/src/argaze/ArUcoMarkers/ArUcoMarker.py
+++ b/src/argaze/ArUcoMarkers/ArUcoMarker.py
@@ -8,6 +8,7 @@ __copyright__ = "Copyright 2023, Ecole Nationale de l'Aviation Civile (ENAC)"
 __license__ = "BSD"
 
 from dataclasses import dataclass, field
+import math
 
 from argaze.ArUcoMarkers import ArUcoMarkersDictionary
 
@@ -25,7 +26,7 @@ class ArUcoMarker():
     identifier: int
     """Index into dictionary"""
 
-    size: float
+    size: float = field(default=math.nan)
     """Size of marker in centimeters."""
 
     corners: numpy.array = field(init=False, repr=False)
@@ -47,7 +48,13 @@ class ArUcoMarker():
         return self.corners[0].mean(axis=0)
 
     def image(self, dpi) -> numpy.array:
-        """Create marker matrix image at a given resolution."""
+        """Create marker matrix image at a given resolution.
+
+        !!! warning
+            Marker size have to be setup before.
+        """
+
+        assert(not math.isnan(self.size))
 
         dimension = round(self.size * dpi / 2.54) # 1 cm = 2.54 inches
         matrix = numpy.zeros((dimension, dimension, 1), dtype="uint8")
@@ -63,6 +70,9 @@ class ArUcoMarker():
             image: image where to draw
             color: marker color (if None, no marker drawn)
             draw_axes: enable marker axes drawing
+
+        !!! warning
+            draw_axes needs marker size and pose estimation.
         """
 
         # Draw marker if required
@@ -70,8 +80,8 @@ class ArUcoMarker():
 
             aruco.drawDetectedMarkers(image, [numpy.array([list(self.corners)])], numpy.array([self.identifier]), color)
 
-        # Draw marker axes if pose has been estimated and if required
-        if self.translation.size == 3 and self.rotation.size == 9 and draw_axes is not None:
+        # Draw marker axes if pose has been estimated, marker have a size and if required
+        if self.translation.size == 3 and self.rotation.size == 9 and not math.isnan(self.size) and draw_axes is not None:
 
             cv2.drawFrameAxes(image, numpy.array(K), numpy.array(D), self.rotation, self.translation, self.size, **draw_axes)
 
diff --git a/src/argaze/DataFeatures.py b/src/argaze/DataFeatures.py
index 688ad4a..a3b7034 100644
--- a/src/argaze/DataFeatures.py
+++ b/src/argaze/DataFeatures.py
@@ -218,7 +218,6 @@ class TimeStampedBuffer(collections.OrderedDict):
             
             raise KeyError(f'No data stored before {ts} timestamp.')
         
-
     def get_last_until(self, ts) -> Tuple[TimeStampType, DataType]:
         """Retreive last item timestamp until a given timestamp value."""
 
@@ -410,6 +409,24 @@ class PipelineStepObject():
         # parent attribute will be setup later by parent it self
         self.__parent = None
 
+    def __enter__(self):
+        """At with statement start."""
+
+        # Start observers
+        for observer_name, observer in self.__observers.items():
+
+            observer.__enter__()
+
+        return self
+
+    def __exit__(self, type, value, traceback):
+        """At with statement end."""
+
+        # End observers
+        for observer_name, observer in self.__observers.items():
+
+            observer.__exit__(type, value, traceback)
+
     @property
     def name(self) -> str:
         """Get layer's name."""
@@ -441,7 +458,6 @@ class PipelineStepObject():
         Returns:
             object_data: dictionary with pipeline step object attributes values.
         """
-
         return {
             "name": self.__name,
             "observers": self.__observers
@@ -655,3 +671,21 @@ class PipelineStepObserver():
     !!! note
         To subscribe to a method call, the inherited class simply needs to define 'on_<method_name>' functions with timestamp and object argument.
     """
+
+    def __enter__(self):
+        """
+        Define abstract __enter__ method to use observer as a context.
+
+        !!! warning
+            This method is called provided that the observed PipelineStepObject is created as a context using a with statement.
+        """
+        return self
+
+    def __exit__(self, type, value, traceback):
+        """
+        Define abstract __exit__ method to use observer as a context.
+
+        !!! warning
+            This method is called provided that the observed PipelineStepObject is created as a context using a with statement.
+        """
+        pass
\ No newline at end of file