Add coordinate for Measurement in SR

This adds support for row 3 and 4 from TID 320.

Resolves #306

src/highdicom/sr/__init__.py

@@ -1,6 +1,7 @@
 """Package for creation of Structured Report (SR) instances."""
 from highdicom.sr.coding import CodedConcept
 from highdicom.sr.content import (
+    CoordinatesForMeasurement,
     FindingSite,
     ImageRegion,
     ImageRegion3D,
@@ -104,6 +105,7 @@
     'ContentItem',
     'ContentSequence',
     'ContentSequence',
+    'CoordinatesForMeasurement',
     'DateContentItem',
     'DateTimeContentItem',
     'DeviceObserverIdentifyingAttributes',

src/highdicom/sr/content.py

@@ -707,6 +707,30 @@ def from_dataset(
         return cast(SourceSeriesForSegmentation, item)
 
 
+class CoordinatesForMeasurement(ScoordContentItem):
+
+    """Content item representing spatial coordinates of a measurement"""
+
+    def __init__(
+            self,
+            graphic_type: Union[GraphicTypeValues, str],
+            graphic_data: np.ndarray,
+            source_image: SourceImageForRegion,
+    ) -> None:
+        graphic_type = GraphicTypeValues(graphic_type)
+        super().__init__(
+            name=CodedConcept(
+                value='121112',
+                meaning='Source of Measurement',
+                scheme_designator='DCM'
+            ),
+            graphic_type=graphic_type,
+            graphic_data=graphic_data,
+            relationship_type=RelationshipTypeValues.INFERRED_FROM,
+        )
+        self.ContentSequence = [source_image]
+
+
 class ImageRegion(ScoordContentItem):
 
     """Content item representing an image region of interest in the

src/highdicom/sr/templates.py

@@ -10,7 +10,7 @@
 
 from highdicom.sr.coding import CodedConcept
 from highdicom.sr.content import (
-    FindingSite,
+    CoordinatesForMeasurement, FindingSite,
     LongitudinalTemporalOffsetFromEvent,
     ImageRegion,
     ImageRegion3D,
@@ -2386,7 +2386,7 @@ def __init__(
         finding_sites: Optional[Sequence[FindingSite]] = None,
         method: Optional[Union[CodedConcept, Code]] = None,
         properties: Optional[MeasurementProperties] = None,
-        referenced_images: Optional[Sequence[SourceImageForMeasurement]] = None,
+        referenced_images: Optional[Sequence[Union[SourceImageForMeasurement, CoordinatesForMeasurement]]] = None,
         referenced_real_world_value_map: Optional[RealWorldValueMap] = None
     ):
         """
@@ -2429,8 +2429,8 @@ def __init__(
             Measurement properties, including evaluations of its normality
             and/or significance, its relationship to a reference population,
             and an indication of its selection from a set of measurements
-        referenced_images: Union[Sequence[highdicom.sr.SourceImageForMeasurement], None], optional
-            Referenced images which were used as sources for the measurement
+        referenced_images: Union[Sequence[Union[highdicom.sr.SourceImageForMeasurement, highdicom.sr.CoordinatesForMeasurement]], None], optional
+            Referenced images or coordinates which were used as sources for the measurement
         referenced_real_world_value_map: Union[highdicom.sr.RealWorldValueMap, None], optional
             Referenced real world value map for referenced source images
 
@@ -2495,10 +2495,10 @@ def __init__(
             content.extend(properties)
         if referenced_images is not None:
             for image in referenced_images:
-                if not isinstance(image, SourceImageForMeasurement):
+                if not isinstance(image, (SourceImageForMeasurement, CoordinatesForMeasurement)):
                     raise TypeError(
                         'Arguments "referenced_images" must have type '
-                        'SourceImageForMeasurement.'
+                        'SourceImageForMeasurement or CoordinatesForMeasurement.'
                     )
                 content.append(image)
         if referenced_real_world_value_map is not None:

tests/test_sr.py

@@ -75,6 +75,7 @@
     VolumetricROIMeasurementsAndQualitativeEvaluations,
     srread,
 )
+from highdicom.sr.content import CoordinatesForMeasurement
 from highdicom.sr.utils import find_content_items
 from highdicom import UID
 
@@ -2141,6 +2142,30 @@ def test_from_invalid_source_image_seg(self):
             )
 
 
+class TestCoordinatesForMeasurement(unittest.TestCase):
+
+    def setUp(self):
+        super().setUp()
+        self.source_image = SourceImageForRegion(
+            referenced_sop_class_uid='1.2.840.10008.5.1.4.1.1.2',
+            referenced_sop_instance_uid='1.2.3.4.5.6.7.8.9.10'
+        )
+
+    def test_construction(self):
+        item = CoordinatesForMeasurement(
+            graphic_type=GraphicTypeValues.MULTIPOINT,
+            graphic_data=np.array([[10, 20], [20, 30]]),
+            source_image=self.source_image
+        )
+
+        assert item.graphic_type == GraphicTypeValues.MULTIPOINT
+        assert item.GraphicData == [10, 20, 20, 30]
+        assert item.relationship_type == RelationshipTypeValues.INFERRED_FROM
+
+        assert len(item.ContentSequence) == 1
+        assert item.ContentSequence[0] == self.source_image
+        assert item.ContentSequence[0].relationship_type == RelationshipTypeValues.SELECTED_FROM
+
 class TestReferencedSegment(unittest.TestCase):
 
     def setUp(self):