Created by: wangxinxin08
cherry-pick https://github.com/PaddlePaddle/PaddleDetection/pull/1440 https://github.com/PaddlePaddle/PaddleDetection/pull/1445 to release/0.4
Created by: wangxinxin08
cherry-pick https://github.com/PaddlePaddle/PaddleDetection/pull/1440 https://github.com/PaddlePaddle/PaddleDetection/pull/1445 to release/0.4