[Bug Fix] Fix TTA resize scale (open-mmlab#334)

* fix tta bug

* modify as suggested

* fix test_tta bug

Author: yamengxi

mmseg/datasets/pipelines/test_time_aug.py

@@ -104,7 +104,7 @@ def __call__(self, results):
         aug_data = []
         if self.img_scale is None and mmcv.is_list_of(self.img_ratios, float):
             h, w = results['img'].shape[:2]
-            img_scale = [(int(h * ratio), int(w * ratio))
+            img_scale = [(int(w * ratio), int(h * ratio))
                          for ratio in self.img_ratios]
         else:
             img_scale = self.img_scale

mmseg/datasets/pipelines/transforms.py

@@ -156,8 +156,9 @@ def _random_scale(self, results):
 
         if self.ratio_range is not None:
             if self.img_scale is None:
-                scale, scale_idx = self.random_sample_ratio(
-                    results['img'].shape[:2], self.ratio_range)
+                h, w = results['img'].shape[:2]
+                scale, scale_idx = self.random_sample_ratio((w, h),
+                                                            self.ratio_range)
             else:
                 scale, scale_idx = self.random_sample_ratio(
                     self.img_scale[0], self.ratio_range)

tests/test_data/test_tta.py

@@ -108,7 +108,7 @@ def test_multi_scale_flip_aug():
     )
     tta_module = build_from_cfg(tta_transform, PIPELINES)
     tta_results = tta_module(results.copy())
-    assert tta_results['scale'] == [(144, 256), (288, 512), (576, 1024)]
+    assert tta_results['scale'] == [(256, 144), (512, 288), (1024, 576)]
     assert tta_results['flip'] == [False, False, False]
 
     tta_transform = dict(
@@ -120,8 +120,8 @@ def test_multi_scale_flip_aug():
     )
     tta_module = build_from_cfg(tta_transform, PIPELINES)
     tta_results = tta_module(results.copy())
-    assert tta_results['scale'] == [(144, 256), (144, 256), (288, 512),
-                                    (288, 512), (576, 1024), (576, 1024)]
+    assert tta_results['scale'] == [(256, 144), (256, 144), (512, 288),
+                                    (512, 288), (1024, 576), (1024, 576)]
     assert tta_results['flip'] == [False, True, False, True, False, True]
 
     tta_transform = dict(