COCO enable bbox with segement annotation

Author: bonhunko

CHANGELOG.md

@@ -41,6 +41,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   (<https://github.com/openvinotoolkit/datumaro/pull/767>)
 - Fix a VOC dataset export when a label contains 'space'
   (<https://github.com/openvinotoolkit/datumaro/pull/771>)
+- Keep 'bbox' annotation when importing a COCO dataset
+  (<https://github.com/openvinotoolkit/datumaro/pull/772>)
 
 ### Changed
 - Wrap title text according to its plot width

datumaro/plugins/data_formats/coco/base.py

@@ -412,17 +412,27 @@ def _load_annotations(self, ann, image_info=None, parsed_annotations=None):
                             rle=rle, label=label_id, id=ann_id, attributes=attributes, group=group
                         )
                     )
-            else:
-                bbox = self._parse_field(ann, "bbox", list)
+
+            bbox = self._parse_field(ann, "bbox", list)
+            if bbox and len(bbox) > 0:
                 if len(bbox) != 4:
                     raise InvalidAnnotationError(
                         f"Bbox has wrong value count {len(bbox)}. Expected 4 values."
                     )
-
                 x, y, w, h = bbox
                 parsed_annotations.append(
-                    Bbox(x, y, w, h, label=label_id, id=ann_id, attributes=attributes, group=group)
+                    Bbox(
+                        x,
+                        y,
+                        w,
+                        h,
+                        label=label_id,
+                        id=ann_id,
+                        attributes=attributes,
+                        group=group,
+                    )
                 )
+
         elif self._task is CocoTask.labels:
             label_id = self._get_label_id(ann)
             parsed_annotations.append(

datumaro/plugins/data_formats/coco/exporter.py

@@ -208,7 +208,10 @@ def find_instance_parts(self, group, img_width, img_height):
 
         anns = boxes + polygons + masks
         leader = anno_tools.find_group_leader(anns)
-        bbox = anno_tools.max_bbox(anns)
+        if len(boxes) > 0:
+            bbox = anno_tools.max_bbox(boxes)
+        else:
+            bbox = anno_tools.max_bbox(anns)
         mask = None
         polygons = [p.points for p in polygons]