[Fix] Fix bbox clamp in pt1.10 (open-mmlab#7074)

Author: RangiLyu

mmdet/models/dense_heads/autoassign_head.py

@@ -197,7 +197,7 @@ def forward_single(self, x, scale, stride):
         # scale the bbox_pred of different level
         # float to avoid overflow when enabling FP16
         bbox_pred = scale(bbox_pred).float()
-        bbox_pred = F.relu(bbox_pred)
+        bbox_pred = bbox_pred.clamp(min=0)
         bbox_pred *= stride
         return cls_score, bbox_pred, centerness
 

mmdet/models/dense_heads/fcos_head.py

@@ -3,7 +3,6 @@
 
 import torch
 import torch.nn as nn
-import torch.nn.functional as F
 from mmcv.cnn import Scale
 from mmcv.runner import force_fp32
 
@@ -155,7 +154,7 @@ def forward_single(self, x, scale, stride):
         # float to avoid overflow when enabling FP16
         bbox_pred = scale(bbox_pred).float()
         if self.norm_on_bbox:
-            bbox_pred = F.relu(bbox_pred)
+            bbox_pred = bbox_pred.clamp(min=0)
             if not self.training:
                 bbox_pred *= stride
         else: