Fix project import with skeletons (#4867)

CHANGELOG.md

@@ -25,6 +25,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 non-ascii paths while adding files from "Connected file share" (issue #4428)
 - Removed unnecessary volumes defined in docker-compose.serverless.yml
 (<https://github.com/openvinotoolkit/cvat/pull/4659>)
+- Project import with skeletons (<https://github.com/opencv/cvat/pull/4867>)
 
 ### Security
 - TDB

cvat/apps/dataset_manager/bindings.py

@@ -524,9 +524,7 @@ class TaskData(InstanceLabelData):
             ]
             shape['attributes'] = [self._import_attribute(label_id, attrib, mutable=True)
                 for attrib in shape['attributes']
-                if self._get_mutable_attribute_id(label_id, attrib.name) or (
+                if self._get_mutable_attribute_id(label_id, attrib.name)
-                    self.soft_attribute_import and attrib.name not in CVAT_INTERNAL_ATTRIBUTES
-                )
             ]
             shape['points'] = list(map(float, shape['points']))
 
@@ -1101,9 +1099,9 @@ class CVATDataExtractorMixin:
     def _read_cvat_anno(self, cvat_frame_anno: Union[ProjectData.Frame, TaskData.Frame], labels: list):
         categories = self.categories()
         label_cat = categories[dm.AnnotationType.label]
-        def map_label(name): return label_cat.find(name)[0]
+        def map_label(name, parent=''): return label_cat.find(name, parent)[0]
         label_attrs = {
-            label['name']: label['attributes']
+            label.get('parent', '') + label['name']: label['attributes']
             for _, label in labels
         }
 
@@ -1198,9 +1196,9 @@ class CvatTaskDataExtractor(dm.SourceExtractor, CVATDataExtractorMixin):
     def _read_cvat_anno(self, cvat_frame_anno: TaskData.Frame, labels: list):
         categories = self.categories()
         label_cat = categories[dm.AnnotationType.label]
-        def map_label(name, parent=""): return label_cat.find(name, parent)[0]
+        def map_label(name, parent=''): return label_cat.find(name, parent)[0]
         label_attrs = {
-            label.get("parent", "") + label['name']: label['attributes']
+            label.get('parent', '') + label['name']: label['attributes']
             for _, label in labels
         }
 
@@ -1562,6 +1560,7 @@ def import_dm_annotations(dm_dataset: dm.Dataset, instance_data: Union[TaskData,
                     for n, v in ann.attributes.items()
                 ]
 
+                points = []
                 if ann.type in shapes:
                     points = []
                     if ann.type == dm.AnnotationType.cuboid_3d:
@@ -1647,6 +1646,11 @@ def import_dm_annotations(dm_dataset: dm.Dataset, instance_data: Union[TaskData,
 
                         if ann.type == dm.AnnotationType.skeleton:
                             for element in ann.elements:
+                                element_keyframe = dm.util.cast(element.attributes.get('keyframe', None), bool) is True
+                                element_outside = dm.util.cast(element.attributes.pop('outside', None), bool) is True
+                                if not element_keyframe and not element_outside:
+                                    continue
+
                                 if element.label not in tracks[track_id]['elements']:
                                     tracks[track_id]['elements'][element.label] = instance_data.Track(
                                         label=label_cat.items[element.label].name,
@@ -1659,7 +1663,6 @@ def import_dm_annotations(dm_dataset: dm.Dataset, instance_data: Union[TaskData,
                                     for n, v in element.attributes.items()
                                 ]
                                 element_occluded = dm.util.cast(element.attributes.pop('occluded', None), bool) is True
-                                element_outside = dm.util.cast(element.attributes.pop('outside', None), bool) is True
                                 element_source = element.attributes.pop('source').lower() \
                                     if element.attributes.get('source', '').lower() in {'auto', 'manual'} else 'manual'
                                 tracks[track_id]['elements'][element.label].shapes.append(instance_data.TrackedShape(

cvat/apps/dataset_manager/formats/cvat.py

@@ -14,7 +14,7 @@ from typing import Callable
 
 from datumaro.components.annotation import (AnnotationType, Bbox, Label,
                                             LabelCategories, Points, Polygon,
-                                            PolyLine)
+                                            PolyLine, Skeleton)
 from datumaro.components.dataset import Dataset, DatasetItem
 from datumaro.components.extractor import (DEFAULT_SUBSET_NAME, Extractor,
                                            Importer)
@@ -119,23 +119,34 @@ class CvatExtractor(Extractor):
         items = OrderedDict()
 
         track = None
+        track_element = None
+        track_shapes = None
         shape = None
+        shape_element = None
         tag = None
         attributes = None
+        element_attributes = None
         image = None
         subset = None
         for ev, el in context:
             if ev == 'start':
                 if el.tag == 'track':
-                    frame_size = tasks_info[int(el.attrib.get('task_id'))]['frame_size'] if el.attrib.get('task_id') else tuple(tasks_info.values())[0]['frame_size']
+                    if track:
-                    track = {
+                        track_element = {
-                        'id': el.attrib['id'],
+                            'id': el.attrib['id'],
-                        'label': el.attrib.get('label'),
+                            'label': el.attrib.get('label'),
-                        'group': int(el.attrib.get('group_id', 0)),
+                        }
-                        'height': frame_size[0],
+                    else:
-                        'width': frame_size[1],
+                        frame_size = tasks_info[int(el.attrib.get('task_id'))]['frame_size'] if el.attrib.get('task_id') else tuple(tasks_info.values())[0]['frame_size']
-                    }
+                        track = {
-                    subset = el.attrib.get('subset')
+                            'id': el.attrib['id'],
+                            'label': el.attrib.get('label'),
+                            'group': int(el.attrib.get('group_id', 0)),
+                            'height': frame_size[0],
+                            'width': frame_size[1],
+                        }
+                        subset = el.attrib.get('subset')
+                        track_shapes = {}
                 elif el.tag == 'image':
                     image = {
                         'name': el.attrib.get('name'),
@@ -145,16 +156,28 @@ class CvatExtractor(Extractor):
                     }
                     subset = el.attrib.get('subset')
                 elif el.tag in cls._SUPPORTED_SHAPES and (track or image):
-                    attributes = {}
+                    if shape and shape['type'] == 'skeleton':
-                    shape = {
+                        element_attributes = {}
-                        'type': None,
+                        shape_element = {
-                        'attributes': attributes,
+                            'type': 'rectangle' if el.tag == 'box' else el.tag,
-                    }
+                            'attributes': element_attributes,
-                    if track:
+                        }
-                        shape.update(track)
+                        shape_element.update(image)
-                        shape['track_id'] = int(track['id'])
+                    else:
-                    if image:
+                        attributes = {}
-                        shape.update(image)
+                        shape = {
+                            'type': 'rectangle' if el.tag == 'box' else el.tag,
+                            'attributes': attributes,
+                        }
+                        shape['elements'] = []
+                        if track_element:
+                            shape.update(track_element)
+                            shape['track_id'] = int(track_element['id'])
+                        elif track:
+                            shape.update(track)
+                            shape['track_id'] = int(track['id'])
+                        if image:
+                            shape.update(image)
                 elif el.tag == 'tag' and image:
                     attributes = {}
                     tag = {
@@ -165,7 +188,19 @@ class CvatExtractor(Extractor):
                     }
                     subset = el.attrib.get('subset')
             elif ev == 'end':
-                if el.tag == 'attribute' and attributes is not None:
+                if el.tag == 'attribute' and element_attributes is not None and shape_element is not None:
+                    attr_value = el.text or ''
+                    attr_type = attribute_types.get(el.attrib['name'])
+                    if el.text in ['true', 'false']:
+                        attr_value = attr_value == 'true'
+                    elif attr_type is not None and attr_type != 'text':
+                        try:
+                            attr_value = float(attr_value)
+                        except ValueError:
+                            pass
+                    element_attributes[el.attrib['name']] = attr_value
+
+                if el.tag == 'attribute' and attributes is not None and shape_element is None:
                     attr_value = el.text or ''
                     attr_type = attribute_types.get(el.attrib['name'])
                     if el.text in ['true', 'false']:
@@ -176,6 +211,37 @@ class CvatExtractor(Extractor):
                         except ValueError:
                             pass
                     attributes[el.attrib['name']] = attr_value
+
+                elif el.tag in cls._SUPPORTED_SHAPES and shape["type"] == "skeleton" and el.tag != "skeleton":
+                    shape_element['label'] = el.attrib.get('label')
+                    shape_element['group'] = int(el.attrib.get('group_id', 0))
+
+                    shape_element['type'] = el.tag
+                    shape_element['z_order'] = int(el.attrib.get('z_order', 0))
+
+                    if el.tag == 'box':
+                        shape_element['points'] = list(map(float, [
+                            el.attrib['xtl'], el.attrib['ytl'],
+                            el.attrib['xbr'], el.attrib['ybr'],
+                        ]))
+                    else:
+                        shape_element['points'] = []
+                        for pair in el.attrib['points'].split(';'):
+                            shape_element['points'].extend(map(float, pair.split(',')))
+
+                    if el.tag == 'points' and el.attrib.get('occluded') == '1':
+                        shape_element['visibility'] = [Points.Visibility.hidden] * (len(shape_element['points']) // 2)
+                    else:
+                        shape_element['occluded'] = (el.attrib.get('occluded') == '1')
+
+                    if el.tag == 'points' and el.attrib.get('outside') == '1':
+                        shape_element['visibility'] = [Points.Visibility.absent] * (len(shape_element['points']) // 2)
+                    else:
+                        shape_element['outside'] = (el.attrib.get('outside') == '1')
+
+                    shape['elements'].append(shape_element)
+                    shape_element = None
+
                 elif el.tag in cls._SUPPORTED_SHAPES:
                     if track is not None:
                         shape['frame'] = el.attrib['frame']
@@ -194,15 +260,22 @@ class CvatExtractor(Extractor):
                             el.attrib['xtl'], el.attrib['ytl'],
                             el.attrib['xbr'], el.attrib['ybr'],
                         ]))
+                    elif el.tag == 'skeleton':
+                        shape['points'] = []
                     else:
                         shape['points'] = []
                         for pair in el.attrib['points'].split(';'):
                             shape['points'].extend(map(float, pair.split(',')))
+                    if track_element:
+                        track_shapes[shape['frame']]['elements'].append(shape)
+                    elif track:
+                        track_shapes[shape['frame']] = shape
+                    else:
+                        frame_desc = items.get((subset, shape['frame']), {'annotations': []})
+                        frame_desc['annotations'].append(
+                            cls._parse_shape_ann(shape, categories))
+                        items[(subset, shape['frame'])] = frame_desc
 
-                    frame_desc = items.get((subset, shape['frame']), {'annotations': []})
-                    frame_desc['annotations'].append(
-                        cls._parse_shape_ann(shape, categories))
-                    items[(subset, shape['frame'])] = frame_desc
                     shape = None
 
                 elif el.tag == 'tag':
@@ -212,7 +285,15 @@ class CvatExtractor(Extractor):
                     items[(subset, tag['frame'])] = frame_desc
                     tag = None
                 elif el.tag == 'track':
-                    track = None
+                    if track_element:
+                        track_element = None
+                    else:
+                        for track_shape in track_shapes.values():
+                            frame_desc = items.get((subset, track_shape['frame']), {'annotations': []})
+                            frame_desc['annotations'].append(
+                                cls._parse_shape_ann(track_shape, categories))
+                            items[(subset, track_shape['frame'])] = frame_desc
+                        track = None
                 elif el.tag == 'image':
                     frame_desc = items.get((subset, image['frame']), {'annotations': []})
                     frame_desc.update({
@@ -377,7 +458,8 @@ class CvatExtractor(Extractor):
                 id=ann_id, attributes=attributes, group=group)
 
         elif ann_type == 'points':
-            return Points(points, label=label_id, z_order=z_order,
+            visibility = ann.get('visibility', None)
+            return Points(points, visibility, label=label_id, z_order=z_order,
                 id=ann_id, attributes=attributes, group=group)
 
         elif ann_type == 'box':
@@ -386,6 +468,14 @@ class CvatExtractor(Extractor):
             return Bbox(x, y, w, h, label=label_id, z_order=z_order,
                 id=ann_id, attributes=attributes, group=group)
 
+        elif ann_type == 'skeleton':
+            elements = []
+            for element in ann.get('elements', []):
+                elements.append(cls._parse_shape_ann(element, categories))
+
+            return Skeleton(elements, label=label_id, z_order=z_order,
+                id=ann_id, attributes=attributes, group=group)
+
         else:
             raise NotImplementedError("Unknown annotation type '%s'" % ann_type)
 
@@ -963,7 +1053,10 @@ def dump_as_cvat_interpolation(dumper, annotations):
                 elements=[],
             ) for element in shape.elements]
         }
-        if isinstance(annotations, ProjectData): track['task_id'] = shape.task_id
+        if isinstance(annotations, ProjectData):
+            track['task_id'] = shape.task_id
+            for element in track['elements']:
+                element.task_id = shape.task_id
         dump_track(counter, annotations.Track(**track))
         counter += 1
 

cvat/apps/dataset_manager/tests/assets/annotations.json

@@ -708,43 +708,6 @@
     ],
     "tracks": []
   },
-  "WiderFace 1.0": {
-    "version": 0,
-    "tags": [
-      {
-        "frame": 0,
-        "label_id": null,
-        "group": 0,
-        "source": "manual",
-        "attributes": []
-      }
-    ],
-    "shapes": [
-      {
-        "type": "rectangle",
-        "occluded": false,
-        "z_order": 0,
-        "points": [7.55, 9.75, 16.44, 15.85],
-        "frame": 0,
-        "label_id": null,
-        "group": 0,
-        "source": "manual",
-        "attributes": []
-      },
-      {
-        "type": "rectangle",
-        "occluded": true,
-        "z_order": 0,
-        "points": [3.55, 27.75, 11.33, 33.71],
-        "frame": 0,
-        "label_id": null,
-        "group": 0,
-        "source": "manual",
-        "attributes": []
-      }
-    ],
-    "tracks": []
-  },
   "VGGFace2 1.0": {
     "version": 0,
     "tags": [],
@@ -1085,7 +1048,6 @@
             "points": [66.45, 147.08, 182.16, 204.56],
             "frame": 0,
             "outside": false,
-            "outside": true,
             "attributes": []
           },
           {
@@ -1215,50 +1177,6 @@
       }
     ]
   },
-  "CVAT for video 1.1 polygon": {
-    "version": 0,
-    "tags": [],
-    "shapes": [],
-    "tracks": [
-      {
-        "frame": 0,
-        "label_id": null,
-        "group": 1,
-        "source": "manual",
-        "shapes": [
-          {
-            "type": "polygon",
-            "occluded": false,
-            "z_order": 0,
-            "points": [24.62, 13.01, 34.88, 20.03, 18.14, 18.08],
-            "frame": 0,
-            "outside": false,
-            "attributes": []
-          },
-          {
-            "type": "polygon",
-            "occluded": false,
-            "z_order": 0,
-            "points": [24.62, 13.01, 34.88, 20.03, 18.14, 18.08],
-            "frame": 1,
-            "outside": true,
-            "attributes": []
-          },
-          {
-            "type": "polygon",
-            "occluded": false,
-            "z_order": 0,
-            "points": [24.62, 13.01, 34.88, 20.03, 18.14, 18.08],
-            "frame": 2,
-            "outside": false,
-            "keyframe": true,
-            "attributes": []
-          }
-        ],
-        "attributes": []
-      }
-    ]
-  },
   "CVAT for video 1.1 attributes in tracks": {
     "version": 0,
     "tags": [],

cvat/apps/engine/backup.py

@@ -173,34 +173,35 @@ class _TaskBackupBase(_BackupBase):
                 source, dest = attribute.pop('spec_id'), 'name'
             attribute[dest] = label_mapping[label]['attributes'][source]
 
-        def _update_label(shape):
+        def _update_label(shape, parent_label=''):
             if 'label_id' in shape:
-                source, dest = shape.pop('label_id'), 'label'
+                source = shape.pop('label_id')
+                shape['label'] = label_mapping[source]['value']
             elif 'label' in shape:
-                source, dest = shape.pop('label'), 'label_id'
+                source = parent_label + shape.pop('label')
-            shape[dest] = label_mapping[source]['value']
+                shape['label_id'] = label_mapping[source]['value']
 
             return source
 
-        def _prepare_shapes(shapes):
+        def _prepare_shapes(shapes, parent_label=''):
             for shape in shapes:
-                label = _update_label(shape)
+                label = _update_label(shape, parent_label)
                 for attr in shape['attributes']:
                     _update_attribute(attr, label)
 
-                _prepare_shapes(shape.get('elements', []))
+                _prepare_shapes(shape.get('elements', []), label)
 
                 self._prepare_meta(allowed_fields, shape)
 
-        def _prepare_tracks(tracks):
+        def _prepare_tracks(tracks, parent_label=''):
             for track in tracks:
-                label = _update_label(track)
+                label = _update_label(track, parent_label)
                 for shape in track['shapes']:
                     for attr in shape['attributes']:
                         _update_attribute(attr, label)
                     self._prepare_meta(allowed_fields, shape)
 
-                _prepare_tracks(track.get('elements', []))
+                _prepare_tracks(track.get('elements', []), label)
 
                 for attr in track['attributes']:
                     _update_attribute(attr, label)
@@ -427,7 +428,7 @@ class _ImporterBase():
             sublabels  = label.pop('sublabels', [])
 
             db_label = models.Label.objects.create(**label_relation, parent=parent_label, **label)
-            label_mapping[label_name] = {
+            label_mapping[(parent_label.name if parent_label else '') + label_name] = {
                 'value': db_label.id,
                 'attributes': {},
             }
@@ -444,7 +445,7 @@ class _ImporterBase():
                 attribute_serializer = AttributeSerializer(data=attribute)
                 attribute_serializer.is_valid(raise_exception=True)
                 db_attribute = attribute_serializer.save(label=db_label)
-                label_mapping[label_name]['attributes'][attribute_name] = db_attribute.id
+                label_mapping[(parent_label.name if parent_label else '') + label_name]['attributes'][attribute_name] = db_attribute.id
 
         return label_mapping
 

cvat/apps/engine/serializers.py

@@ -816,12 +816,13 @@ class ProjectWriteSerializer(serializers.ModelSerializer):
                 sublabels = label.pop('sublabels', [])
                 svg = label.pop('svg', '')
                 db_label = LabelSerializer.update_instance(label, instance, parent_label)
-                update_labels(sublabels, parent_label=db_label)
+                if not label.get('deleted'):
+                    update_labels(sublabels, parent_label=db_label)
 
-                if label.get('id') is None and db_label.type == str(models.LabelType.SKELETON):
+                    if label.get('id') is None and db_label.type == str(models.LabelType.SKELETON):
-                    for db_sublabel in list(db_label.sublabels.all()):
+                        for db_sublabel in list(db_label.sublabels.all()):
-                        svg = svg.replace(f'data-label-name="{db_sublabel.name}"', f'data-label-id="{db_sublabel.id}"')
+                            svg = svg.replace(f'data-label-name="{db_sublabel.name}"', f'data-label-id="{db_sublabel.id}"')
-                    models.Skeleton.objects.create(root=db_label, svg=svg)
+                        models.Skeleton.objects.create(root=db_label, svg=svg)
 
         update_labels(labels)
 

site/content/en/docs/manual/advanced/formats/format-cvat.md

@@ -9,10 +9,10 @@ This is the native CVAT annotation format. It supports all CVAT annotations
 features, so it can be used to make data backups.
 
 - supported annotations CVAT for Images: Rectangles, Polygons, Polylines,
-  Points, Cuboids, Tags, Tracks
+  Points, Cuboids, Skeletons, Tags, Tracks
 
 - supported annotations CVAT for Videos: Rectangles, Polygons, Polylines,
-  Points, Cuboids, Tracks
+  Points, Cuboids, Skeletons, Tracks
 
 - attributes are supported
 

site/content/en/docs/manual/advanced/xml_format.md

@@ -38,6 +38,7 @@ In annotation mode each image tag has `width` and `height` attributes for the sa
       <labels>
         <label>
           <name>String: name of the label (e.g. car, person)</name>
+          <type>String: any, bbox, cuboid, cuboid_3d, ellipse, polygon, polyline, points, skeleton, tag</type>
           <attributes>
             <attribute>
               <name>String: attribute name</name>
@@ -49,6 +50,8 @@ ex. value 2
 ex. value 3</values>
             </attribute>
           </attributes>
+          <svg>String: label representation in svg, only for skeletons</svg>
+          <parent>String: label parent name, only for skeletons</parent>
         </label>
       </labels>
       <segments>
@@ -81,7 +84,7 @@ On each image it is possible to have many different objects. Each object can hav
 If an annotation task is created with `z_order` flag then each object will have `z_order` attribute which is used
 to draw objects properly when they are intersected (if `z_order` is bigger the object is closer to camera).
 In previous versions of the format only `box` shape was available.
-In later releases `polygon`, `polyline`, `points` and `tags` were added. Please see below for more details:
+In later releases `polygon`, `polyline`, `points`, `skeletons` and `tags` were added. Please see below for more details:
 
 ```xml
 <?xml version="1.0" encoding="utf-8"?>
@@ -117,6 +120,14 @@ In later releases `polygon`, `polyline`, `points` and `tags` were added. Please
       <attribute name="String: an attribute name">String: the attribute value</attribute>
       ...
     </tag>
+    <skeleton label="String: the associated label" occluded="Number: 0 - False, 1 - True" z_order="Number: z-order of the object">
+      <points label="String: the associated label" occluded="Number: 0 - False, 1 - True" outside="Number: 0 - False, 1 - True" points="x0,y0;x1,y1" z_order="0">
+        <attribute name="String: an attribute name">String: the attribute value</attribute>
+      </points>
+      ...
+      <attribute name="String: an attribute name">String: the attribute value</attribute>
+      ...
+    </skeleton>
     ...
   </image>
   ...
@@ -161,6 +172,34 @@ Example:
           <attributes>
           </attributes>
         </label>
+        <label>
+          <name>s1</name>
+          <type>skeleton</type>
+          <attributes>
+          </attributes>
+          <svg>&lt;line x1="36.87290954589844" y1="47.732025146484375" x2="86.87290954589844" y2="10.775501251220703" stroke="black" data-type="edge" data-node-from="2" stroke-width="0.5" data-node-to="3"&gt;&lt;/line&gt;&lt;line x1="25.167224884033203" y1="22.64841079711914" x2="36.87290954589844" y2="47.732025146484375" stroke="black" data-type="edge" data-node-from="1" stroke-width="0.5" data-node-to="2"&gt;&lt;/line&gt;&lt;circle r="1.5" stroke="black" fill="#b3b3b3" cx="25.167224884033203" cy="22.64841079711914" stroke-width="0.1" data-type="element node" data-element-id="1" data-node-id="1" data-label-name="1"&gt;&lt;/circle&gt;&lt;circle r="1.5" stroke="black" fill="#b3b3b3" cx="36.87290954589844" cy="47.732025146484375" stroke-width="0.1" data-type="element node" data-element-id="2" data-node-id="2" data-label-name="2"&gt;&lt;/circle&gt;&lt;circle r="1.5" stroke="black" fill="#b3b3b3" cx="86.87290954589844" cy="10.775501251220703" stroke-width="0.1" data-type="element node" data-element-id="3" data-node-id="3" data-label-name="3"&gt;&lt;/circle&gt;</svg>
+        </label>
+        <label>
+          <name>1</name>
+          <type>points</type>
+          <attributes>
+          </attributes>
+          <parent>s1</parent>
+        </label>
+        <label>
+          <name>2</name>
+          <type>points</type>
+          <attributes>
+          </attributes>
+          <parent>s1</parent>
+        </label>
+        <label>
+          <name>3</name>
+          <type>points</type>
+          <attributes>
+          </attributes>
+          <parent>s1</parent>
+        </label>
       </labels>
       <segments>
         <segment>
@@ -190,6 +229,14 @@ Example:
     </points>
     <tag label="good_frame" source="manual">
     </tag>
+    <skeleton label="s1" occluded="0" source="manual" points="" rotation="0.00" z_order="0">
+      <points label="1" occluded="0" source="manual" outside="0" points="54.47,94.81" z_order="0">
+      </points>
+      <points label="2" occluded="0" source="manual" outside="0" points="68.02,162.34" z_order="0">
+      </points>
+      <points label="3" occluded="0" source="manual" outside="0" points="125.87,62.85" z_order="0">
+      </points>
+    </skeleton>
   </image>
 </annotations>
 ```
@@ -206,7 +253,7 @@ cloned for each location (a known redundancy).
 <?xml version="1.0" encoding="utf-8"?>
 <annotations>
   ...
-  <track id="Number: id of the track (doesn't have any special meeting" label="String: the associated label" source="manual or auto">
+  <track id="Number: id of the track (doesn't have any special meeting)" label="String: the associated label" source="manual or auto">
     <box frame="Number: frame" xtl="Number: float" ytl="Number: float" xbr="Number: float" ybr="Number: float" outside="Number: 0 - False, 1 - True" occluded="Number: 0 - False, 1 - True" keyframe="Number: 0 - False, 1 - True">
       <attribute name="String: an attribute name">String: the attribute value</attribute>
       ...
@@ -222,6 +269,17 @@ cloned for each location (a known redundancy).
     </points>
     ...
   </track>
+  <track id="Number: id of the track (doesn't have any special meeting)" label="String: the associated label" source="manual or auto">
+    <skeleton frame="Number: frame" outside="Number: 0 - False, 1 - True" occluded="Number: 0 - False, 1 - True" keyframe="Number: 0 - False, 1 - True">
+    </skeleton>
+    ...
+    <track id="Number: id of the track (doesn't have any special meeting)" label="String: the associated label" source="manual or auto">
+      <points frame="Number: frame" outside="Number: 0 - False, 1 - True" occluded="Number: 0 - False, 1 - True" keyframe="Number: 0 - False, 1 - True" points="x0,y0;x1,y1">
+      </points>
+      ...
+    </track>
+    ...
+  </track>
   ...
 </annotations>
 ```
@@ -254,6 +312,34 @@ Example:
           <attributes>
           </attributes>
         </label>
+        <label>
+          <name>s1</name>
+          <type>skeleton</type>
+          <attributes>
+          </attributes>
+          <svg>&lt;line x1="36.87290954589844" y1="47.732025146484375" x2="86.87290954589844" y2="10.775501251220703" stroke="black" data-type="edge" data-node-from="2" stroke-width="0.5" data-node-to="3"&gt;&lt;/line&gt;&lt;line x1="25.167224884033203" y1="22.64841079711914" x2="36.87290954589844" y2="47.732025146484375" stroke="black" data-type="edge" data-node-from="1" stroke-width="0.5" data-node-to="2"&gt;&lt;/line&gt;&lt;circle r="1.5" stroke="black" fill="#b3b3b3" cx="25.167224884033203" cy="22.64841079711914" stroke-width="0.1" data-type="element node" data-element-id="1" data-node-id="1" data-label-name="1"&gt;&lt;/circle&gt;&lt;circle r="1.5" stroke="black" fill="#b3b3b3" cx="36.87290954589844" cy="47.732025146484375" stroke-width="0.1" data-type="element node" data-element-id="2" data-node-id="2" data-label-name="2"&gt;&lt;/circle&gt;&lt;circle r="1.5" stroke="black" fill="#b3b3b3" cx="86.87290954589844" cy="10.775501251220703" stroke-width="0.1" data-type="element node" data-element-id="3" data-node-id="3" data-label-name="3"&gt;&lt;/circle&gt;</svg>
+        </label>
+        <label>
+          <name>1</name>
+          <type>points</type>
+          <attributes>
+          </attributes>
+          <parent>s1</parent>
+        </label>
+        <label>
+          <name>2</name>
+          <type>points</type>
+          <attributes>
+          </attributes>
+          <parent>s1</parent>
+        </label>
+        <label>
+          <name>3</name>
+          <type>points</type>
+          <attributes>
+          </attributes>
+          <parent>s1</parent>
+        </label>
       </labels>
       <segments>
         <segment>
@@ -288,5 +374,61 @@ Example:
     <polygon frame="14" points="313.74,233.16;331.11,220.00;359.53,243.16;333.21,283.16;287.95,274.74" outside="1" occluded="0" keyframe="1">
     </polygon>
   </track>
+  <track id="1" label="s1" source="manual">
+    <skeleton frame="0" outside="0" occluded="0" keyframe="1" points="" z_order="0">
+    </skeleton>
+    <skeleton frame="1" outside="1" occluded="0" keyframe="1" points="" z_order="0">
+    </skeleton>
+    <skeleton frame="6" outside="0" occluded="0" keyframe="1" points="" z_order="0">
+    </skeleton>
+    <skeleton frame="7" outside="1" occluded="0" keyframe="1" points="" z_order="0">
+    </skeleton>
+    <skeleton frame="13" outside="0" occluded="0" keyframe="0" points="" z_order="0">
+    </skeleton>
+    <skeleton frame="14" outside="1" occluded="0" keyframe="1" points="" z_order="0">
+    </skeleton>
+    <track id="0" label="1" source="manual" task_id="20" subset="default_1">
+      <points frame="0" outside="0" occluded="0" keyframe="1" points="112.07,258.59" z_order="0">
+      </points>
+      <points frame="1" outside="1" occluded="0" keyframe="1" points="112.07,258.59" z_order="0">
+      </points>
+      <points frame="6" outside="0" occluded="0" keyframe="0" points="120.07,270.59" z_order="0">
+      </points>
+      <points frame="7" outside="1" occluded="0" keyframe="1" points="120.07,270.59" z_order="0">
+      </points>
+      <points frame="13" outside="0" occluded="0" keyframe="0" points="112.07,258.59" z_order="0">
+      </points>
+      <points frame="14" outside="1" occluded="0" keyframe="1" points="112.07,258.59" z_order="0">
+      </points>
+    </track>
+    <track id="1" label="2" source="manual" task_id="20" subset="default_1">
+      <points frame="0" outside="0" occluded="0" keyframe="1" points="127.87,333.23" z_order="0">
+      </points>
+      <points frame="1" outside="1" occluded="0" keyframe="1" points="127.87,333.23" z_order="0">
+      </points>
+      <points frame="6" outside="0" occluded="0" keyframe="0" points="140.87,350.23" z_order="0">
+      </points>
+      <points frame="7" outside="1" occluded="0" keyframe="1" points="140.87,350.23" z_order="0">
+      </points>
+      <points frame="13" outside="0" occluded="0" keyframe="0" points="127.87,333.23" z_order="0">
+      </points>
+      <points frame="14" outside="1" occluded="0" keyframe="1" points="127.87,333.23" z_order="0">
+      </points>
+    </track>
+    <track id="2" label="3" source="manual" task_id="20" subset="default_1">
+      <points frame="0" outside="0" occluded="0" keyframe="1" points="195.37,223.27" z_order="0">
+      </points>
+      <points frame="1" outside="1" occluded="0" keyframe="1" points="195.37,223.27" z_order="0">
+      </points>
+      <points frame="6" outside="0" occluded="0" keyframe="0" points="210.37,260.27" z_order="0">
+      </points>
+      <points frame="7" outside="1" occluded="0" keyframe="1" points="210.37,260.27" z_order="0">
+      </points>
+      <points frame="13" outside="0" occluded="0" keyframe="0" points="195.37,223.27" z_order="0">
+      </points>
+      <points frame="14" outside="1" occluded="0" keyframe="1" points="195.37,223.27" z_order="0">
+      </points>
+    </track>
+  </track>
 </annotations>
 ```