Fix image classification module error

Author: nepeplwu

paddlehub/module/cv_module.py

@@ -70,6 +70,7 @@ def validation_step(self, batch: int, batch_idx: int) -> dict:
         '''
         images = batch[0]
         labels = paddle.unsqueeze(batch[1], axis=-1)
+        labels = labels.astype('int64')
 
         preds, feature = self(images)
 
@@ -104,7 +105,7 @@ def predict(self, images: List[np.ndarray], batch_size: int = 1, top_k: int = 1)
                     batch_data.append(image)
                 except:
                     pass
-            batch_image = np.array(batch_data)
+            batch_image = np.array(batch_data, dtype='float32')
             preds, feature = self(paddle.to_tensor(batch_image))
             preds = F.softmax(preds, axis=1).numpy()
             pred_idxs = np.argsort(preds)[:, ::-1][:, :top_k]