Enable coco format to import bbox annotations (#1360)

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### Summary

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Resolves #111 and #222.
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CHANGELOG.md

@@ -81,6 +81,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   (<https://github.com/openvinotoolkit/datumaro/pull/1262>)
 - Fix explore command without project
   (<https://github.com/openvinotoolkit/datumaro/pull/1271>)
+- Fix enable COCO to import only bboxes
+  (<https://github.com/openvinotoolkit/datumaro/pull/1360>)
 
 ## Jan. 2024 Release 1.5.2
 ### Enhancements

src/datumaro/plugins/data_formats/coco/base.py

@@ -1,4 +1,4 @@
-# Copyright (C) 2019-2022 Intel Corporation
+# Copyright (C) 2019-2024 Intel Corporation
 #
 # SPDX-License-Identifier: MIT
 
@@ -505,7 +505,12 @@ def _load_annotations(self, ann, image_info=None, parsed_annotations=None):
                     )
                 )
 
-            segmentation = self._parse_field(ann, "segmentation", (list, dict))
+            try:
+                segmentation = self._parse_field(ann, "segmentation", (list, dict))
+            except MissingFieldError as e:
+                log.warn(str(e))
+                segmentation = None
+
             if segmentation and segmentation != [[]]:
                 rle = None
 

tests/unit/test_coco_format.py

@@ -1255,7 +1255,8 @@ def test_can_report_missing_item_field(self):
 
     @mark_requirement(Requirements.DATUM_ERROR_REPORTING)
     def test_can_report_missing_ann_field(self):
-        for field in ["id", "image_id", "segmentation", "iscrowd", "category_id", "bbox"]:
+        # https://github.com/openvinotoolkit/datumaro/issues/1344 requires to make "segmentation" optional
+        for field in ["id", "image_id", "iscrowd", "category_id", "bbox"]:
             with self.subTest(field=field):
                 with TestDir() as test_dir:
                     ann_path = self._get_dummy_annotation_path(test_dir)