[Fix] Check the compatibility of inferencer's input/output

mmpose/apis/inferencers/pose2d_inferencer.py

@@ -307,6 +307,15 @@ def __call__(
         else:
             inputs = self._inputs_to_list(inputs)
 
+        # check the compatibility between inputs/outputs
+        if not self._video_input and len(inputs) > 0:
+            vis_out_dir = visualize_kwargs.get('vis_out_dir', None)
+            if vis_out_dir is not None:
+                _, file_extension = os.path.splitext(vis_out_dir)
+                assert not file_extension, f'the argument `vis_out_dir` ' \
+                    f'should be a folder while the input contains multiple ' \
+                    f'images, but got {vis_out_dir}'
+
         forward_kwargs['bbox_thr'] = preprocess_kwargs.get('bbox_thr', -1)
         inputs = self.preprocess(
             inputs, batch_size=batch_size, **preprocess_kwargs)

mmpose/apis/inferencers/pose3d_inferencer.py

@@ -392,6 +392,15 @@ def __call__(
         else:
             inputs = self._inputs_to_list(inputs)
 
+        # check the compatibility between inputs/outputs
+        if not self._video_input and len(inputs) > 0:
+            vis_out_dir = visualize_kwargs.get('vis_out_dir', None)
+            if vis_out_dir is not None:
+                _, file_extension = os.path.splitext(vis_out_dir)
+                assert not file_extension, f'the argument `vis_out_dir` ' \
+                    f'should be a folder while the input contains multiple ' \
+                    f'images, but got {vis_out_dir}'
+
         inputs = self.preprocess(
             inputs, batch_size=batch_size, **preprocess_kwargs)
 

tests/test_apis/test_inferencers/test_pose2d_inferencer.py

@@ -144,6 +144,10 @@ def test_call(self):
         self.assertSequenceEqual(results1['predictions'][0][0]['keypoints'],
                                  results3['predictions'][3][0]['keypoints'])
 
+        with self.assertRaises(AssertionError):
+            for res in inferencer(inputs, vis_out_dir=f'{tmp_dir}/1.jpg'):
+                pass
+
         # `inputs` is path to a video
         inputs = 'tests/data/posetrack18/videos/000001_mpiinew_test/' \
                  '000001_mpiinew_test.mp4'