refactor: remove Frame.uid field

CHANGELOG.md

@@ -108,3 +108,4 @@ Other breaking changes:
 - the `fromdict()` and `asdict()` methods in `raillabel.format` classes have been replaced with `from_json()` and `to_json` respectively
 - `raillabel.format.Transform` fields have been changed by `pos -> position` and `quad -> quaternion` to make it more explicit
 - `raillabel.format.FrameInterval` fields have been changed by `frame_start -> start` and `frame_end -> end` to make it more concise
+- `raillabel.format.Frame.uid` field has been removed to avoid redundant information

raillabel/format/frame.py

@@ -20,8 +20,6 @@ class Frame:
 
     Parameters
     ----------
-    uid: int
-        Number of the frame within the annotation file. Must be unique.
     timestamp: decimal.Decimal, optional
         Timestamp containing the Unix epoch time of the frame with up to nanosecond precision.
     sensors: dict of raillabel.format.SensorReference, optional
@@ -42,7 +40,6 @@ class Frame:
 
     """
 
-    uid: int
     timestamp: decimal.Decimal | None = None
     sensors: dict[str, SensorReference] = field(default_factory=dict)
     frame_data: dict[str, Num] = field(default_factory=dict)
@@ -71,7 +68,6 @@ def object_data(self) -> dict[str, dict[str, type[_ObjectAnnotation]]]:
     @classmethod
     def fromdict(
         cls,
-        uid: str,
         data_dict: dict,
         objects: dict[str, Object],
         sensors: dict[str, Sensor],
@@ -96,7 +92,6 @@ def fromdict(
 
         """
         return Frame(
-            uid=int(uid),
             timestamp=cls._timestamp_fromdict(data_dict),
             sensors=cls._sensors_fromdict(data_dict, sensors),
             frame_data=cls._frame_data_fromdict(data_dict, sensors),

raillabel/format/object.py

@@ -98,7 +98,7 @@ def frame_intervals(self, frames: dict[int, Frame]) -> list[FrameInterval]:
 
         """
         frame_uids_containing_object = [
-            frame.uid for frame in frames.values() if self._is_object_in_frame(frame)
+            frame_uid for frame_uid, frame in frames.items() if self._is_object_in_frame(frame)
         ]
 
         return FrameInterval.from_frame_uids(frame_uids_containing_object)
@@ -150,11 +150,11 @@ def _filtered_annotations(self, frame: Frame) -> list[t.Any]:
 
     def _collect_pointer_ids_per_frame(self, frames: dict[int, Frame]) -> dict[int, set[str]]:
         pointer_ids_per_frame: dict[int, set[str]] = {}
-        for frame in frames.values():
-            pointer_ids_per_frame[frame.uid] = set()
+        for frame_uid, frame in frames.items():
+            pointer_ids_per_frame[frame_uid] = set()
 
             for annotation in self._filtered_annotations(frame):
-                pointer_ids_per_frame[frame.uid].add(annotation.name)  # type: ignore
+                pointer_ids_per_frame[frame_uid].add(annotation.name)  # type: ignore
 
         return pointer_ids_per_frame
 

raillabel/format/scene.py

@@ -173,7 +173,7 @@ def _frames_fromdict(
     ) -> dict[int, Frame]:
         frames = {}
         for frame_uid, frame_dict in frames_dict.items():
-            frames[int(frame_uid)] = Frame.fromdict(frame_uid, frame_dict, objects, sensors)
+            frames[int(frame_uid)] = Frame.fromdict(frame_dict, objects, sensors)
 
         return frames
 

tests/test_raillabel/format/test_frame.py

@@ -42,7 +42,6 @@ def frame_dict(
 @pytest.fixture
 def frame(sensor_reference_camera, num, all_annotations) -> dict:
     return Frame(
-        uid=0,
         timestamp=Decimal("1632321743.100000072"),
         sensors={sensor_reference_camera.sensor.uid: sensor_reference_camera},
         frame_data={num.name: num},
@@ -55,7 +54,6 @@ def frame(sensor_reference_camera, num, all_annotations) -> dict:
 
 def test_fromdict_sensors(sensor_reference_camera_dict, sensor_reference_camera, sensor_camera):
     frame = Frame.fromdict(
-        uid=0,
         data_dict={
             "frame_properties": {
                 "timestamp": "1632321743.100000072",
@@ -66,14 +64,12 @@ def test_fromdict_sensors(sensor_reference_camera_dict, sensor_reference_camera,
         objects={},
     )
 
-    assert frame.uid == 0
     assert frame.timestamp == Decimal("1632321743.100000072")
     assert frame.sensors == {sensor_reference_camera.sensor.uid: sensor_reference_camera}
 
 
 def test_fromdict_frame_data(num, num_dict, sensor_camera):
     frame = Frame.fromdict(
-        uid=1,
         data_dict={"frame_properties": {"frame_data": {"num": [num_dict]}}},
         sensors={sensor_camera.uid: sensor_camera},
         objects={},
@@ -91,7 +87,6 @@ def test_fromdict_annotations(
     all_annotations,
 ):
     frame = Frame.fromdict(
-        uid=2,
         data_dict={
             "objects": {
                 object_person.uid: object_data_person_dict,
@@ -113,7 +108,6 @@ def test_asdict_sensors(
     sensor_reference_camera,
 ):
     frame = Frame(
-        uid=0,
         timestamp=Decimal("1632321743.100000072"),
         sensors={sensor_reference_camera.sensor.uid: sensor_reference_camera},
     )
@@ -127,15 +121,15 @@ def test_asdict_sensors(
 
 
 def test_asdict_frame_data(num, num_dict):
-    frame = Frame(uid=0, frame_data={num.name: num})
+    frame = Frame(frame_data={num.name: num})
 
     assert frame.asdict() == {"frame_properties": {"frame_data": {"num": [num_dict]}}}
 
 
 def test_asdict_object_data(
     object_data_person_dict, object_person, object_data_train_dict, object_train, all_annotations
 ):
-    frame = Frame(uid=0, annotations=all_annotations)
+    frame = Frame(annotations=all_annotations)
 
     assert frame.asdict() == {
         "objects": {
@@ -147,7 +141,6 @@ def test_asdict_object_data(
 
 def test_object_data(object_person, object_train, bbox, cuboid, poly2d, poly3d, seg3d, bbox_train):
     frame = Frame(
-        uid=2,
         annotations={
             bbox.uid: bbox,
             poly2d.uid: poly2d,

tests/test_raillabel/format/test_object.py

@@ -8,7 +8,7 @@
 import sys
 import typing as t
 from pathlib import Path
-from uuid import UUID, uuid4
+from uuid import uuid4
 
 import pytest
 
@@ -405,11 +405,11 @@ def build_annotation(name: str, object: Object, attributes: dict = {}) -> t.Unio
 
 def build_frame(uid: int, raw_object_data: dict[Object, list[t.Union[Bbox, Cuboid]]]) -> Frame:
     annotations = {}
-    for object, object_data in raw_object_data.items():
+    for object_data in raw_object_data.values():
         for annotation in object_data:
             annotations[annotation.uid] = annotation
 
-    return Frame(uid=uid, annotations=annotations)
+    return Frame(annotations=annotations)
 
 
 def build_object(type: str) -> Object:

tests/test_raillabel/format/test_scene.py

@@ -194,7 +194,7 @@ def test_fromdict_frames(
                 "coordinate_systems": coordinate_systems_dict,
                 "objects": objects_dict,
                 "frames": {
-                    str(frame.uid): frame_dict,
+                    "0": frame_dict,
                 },
                 "frame_intervals": [
                     {
@@ -208,7 +208,7 @@ def test_fromdict_frames(
     )
 
     assert scene.frames == {
-        frame.uid: frame,
+        0: frame,
     }
 
 
@@ -300,7 +300,7 @@ def test_asdict_frames(
         sensors=sensors,
         objects=objects,
         frames={
-            frame.uid: frame,
+            "0": frame,
         },
     )
 
@@ -311,7 +311,7 @@ def test_asdict_frames(
             "coordinate_systems": coordinate_systems_dict,
             "objects": objects_dict,
             "frames": {
-                str(frame.uid): frame_dict,
+                "0": frame_dict,
             },
             "frame_intervals": [
                 {