Fix converter for Pascal VOC format

CHANGELOG.md

@@ -32,6 +32,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Added a label "face" for bounding boxes in Wider Face (<https://github.com/openvinotoolkit/datumaro/pull/215>)
 - Allowed adding "difficult", "truncated", "occluded" attributes when converting to Pascal VOC if these attributes are not present (<https://github.com/openvinotoolkit/datumaro/pull/216>)
 - Empty lines in YOLO annotations are ignored (<https://github.com/openvinotoolkit/datumaro/pull/221>)
+- Export in VOC format when no image info is available (<https://github.com/openvinotoolkit/datumaro/pull/239>)
 
 ### Security
 -

datumaro/plugins/voc_format/converter.py

@@ -201,7 +201,7 @@ def save_subsets(self):
                     ET.SubElement(source_elem, 'annotation').text = 'Unknown'
                     ET.SubElement(source_elem, 'image').text = 'Unknown'
 
-                    if item.has_image:
+                    if item.has_image and item.image.has_size:
                         h, w = item.image.size
                         size_elem = ET.SubElement(root_elem, 'size')
                         ET.SubElement(size_elem, 'width').text = str(w)

tests/test_voc_format.py

@@ -763,4 +763,30 @@ def test_inplace_save_writes_only_updated_data(self):
             self.assertFalse(osp.isfile(
                 osp.join(path, 'SegmentationObject', '3.png')))
             self.assertFalse(osp.isfile(
-                osp.join(path, 'SegmentationClass', '3.png')))
+                osp.join(path, 'SegmentationClass', '3.png')))
+
+    def test_can_save_dataset_with_no_data_images(self):
+        class TestExtractor(TestExtractorBase):
+            def __iter__(self):
+                return iter([
+                    DatasetItem(id='frame1', subset='test',
+                        image=Image(path='frame1.jpg'),
+                        annotations=[
+                            Bbox(1.0, 2.0, 3.0, 4.0,
+                                attributes={
+                                    'difficult': False,
+                                    'truncated': False,
+                                    'occluded': False
+                                },
+                                id=1, label=0, group=1
+                            )
+                        ]
+                    )
+                ])
+
+            def categories(self):
+                return VOC.make_voc_categories()
+
+        with TestDir() as test_dir:
+            self._test_save_and_load(TestExtractor(),
+                partial(VocConverter.convert, label_map='voc'), test_dir)