fix deploy infer when rotate detection is empty (#7367)

deploy/python/infer.py

@@ -158,9 +158,6 @@ class Detector(object):
         assert isinstance(np_boxes_num, np.ndarray), \
             '`np_boxes_num` should be a `numpy.ndarray`'
 
-        if np_boxes_num.sum() <= 0:
-            print('[WARNNING] No object detected.')
-            result = {'boxes': np.zeros([0, 6]), 'boxes_num': np_boxes_num}
         result = {k: v for k, v in result.items() if v is not None}
         return result
 
@@ -434,7 +431,7 @@ class Detector(object):
         if not os.path.exists(self.output_dir):
             os.makedirs(self.output_dir)
         out_path = os.path.join(self.output_dir, video_out_name)
-        fourcc = cv2.VideoWriter_fourcc(*'mp4v')
+        fourcc = cv2.VideoWriter_fourcc(* 'mp4v')
         writer = cv2.VideoWriter(out_path, fourcc, fps, (width, height))
         index = 1
         while (1):