fix a bug when scaling images on cpu (#1405)

Author: neonhuang

paddleseg/core/infer.py

@@ -99,13 +99,15 @@ def get_reverse_list(ori_shape, transforms):
 def reverse_transform(pred, ori_shape, transforms, mode='nearest'):
     """recover pred to origin shape"""
     reverse_list = get_reverse_list(ori_shape, transforms)
+    intTypeList = [paddle.int8, paddle.int16, paddle.int32, paddle.int64]
+    dtype = pred.dtype
     for item in reverse_list[::-1]:
         if item[0] == 'resize':
             h, w = item[1][0], item[1][1]
-            if paddle.get_device() == 'cpu':
-                pred = paddle.cast(pred, 'uint8')
+            if paddle.get_device() == 'cpu' and dtype in intTypeList:
+                pred = paddle.cast(pred, 'float32')
                 pred = F.interpolate(pred, (h, w), mode=mode)
-                pred = paddle.cast(pred, 'int32')
+                pred = paddle.cast(pred, dtype)
             else:
                 pred = F.interpolate(pred, (h, w), mode=mode)
         elif item[0] == 'padding':