[Fix]: Fix dim mismatch in batch test/inference of DBNet (#383)

Modification
1.change the dbnet output dim
2.change the input dim for DBloss

.gitignore

@@ -138,3 +138,4 @@ workspace.code-workspace
 results
 mmocr/core/font.TTF
 workdirs/
+.history/

mmocr/models/textdet/dense_heads/db_head.py

@@ -66,7 +66,7 @@ class DBHead(HeadMixin, BaseModule):
         thr_map = self.threshold(inputs)
         binary_map = self.diff_binarize(prob_map, thr_map, k=50)
         outputs = torch.cat((prob_map, thr_map, binary_map), dim=1)
-        return (outputs, )
+        return outputs
 
     def _init_thr(self, inner_channels, bias=False):
         in_channels = inner_channels

mmocr/models/textdet/losses/db_loss.py

@@ -133,8 +133,6 @@ class DBLoss(nn.Module):
         assert isinstance(gt_thr, list)
         assert isinstance(gt_thr_mask, list)
 
-        preds = preds[0]
-
         pred_prob = preds[:, 0, :, :]
         pred_thr = preds[:, 1, :, :]
         pred_db = preds[:, 2, :, :]