diff --git a/python/ch_ppocr_mobile_v2_cls/utils.py b/python/ch_ppocr_mobile_v2_cls/utils.py
index edbd6a2..6fd2865 100755
--- a/python/ch_ppocr_mobile_v2_cls/utils.py
+++ b/python/ch_ppocr_mobile_v2_cls/utils.py
@@ -19,7 +19,7 @@ import imghdr
 def get_image_file_list(img_file):
     imgs_lists = []
     if img_file is None or not os.path.exists(img_file):
-        raise ValueError("not found any img file in {}".format(img_file))
+        raise FileNotFoundError(f"not found any img file in {img_file}")
 
     img_end = {'jpg', 'bmp', 'png', 'jpeg', 'rgb', 'tif', 'tiff', 'gif', 'GIF'}
     if os.path.isfile(img_file) and imghdr.what(img_file) in img_end:
@@ -30,7 +30,7 @@ def get_image_file_list(img_file):
             if os.path.isfile(file_path) and imghdr.what(file_path) in img_end:
                 imgs_lists.append(file_path)
     if len(imgs_lists) == 0:
-        raise ValueError("not found any img file in {}".format(img_file))
+        raise FileNotFoundError(f"not found any img file in {img_file}")
     return imgs_lists
 
 
diff --git a/python/ch_ppocr_server_v2_det/utils.py b/python/ch_ppocr_server_v2_det/utils.py
index a3ac890..4ed6e55 100755
--- a/python/ch_ppocr_server_v2_det/utils.py
+++ b/python/ch_ppocr_server_v2_det/utils.py
@@ -314,7 +314,8 @@ class DBPostProcess(object):
         bitmap = _bitmap
         height, width = bitmap.shape
 
-        outs = cv2.findContours((bitmap * 255).astype(np.uint8), cv2.RETR_LIST,
+        outs = cv2.findContours((bitmap * 255).astype(np.uint8),
+                                cv2.RETR_LIST,
                                 cv2.CHAIN_APPROX_SIMPLE)
         if len(outs) == 3:
             img, contours, _ = outs[0], outs[1], outs[2]
diff --git a/python/rapidOCR.py b/python/rapidOCR.py
index a75418e..8c09c04 100644
--- a/python/rapidOCR.py
+++ b/python/rapidOCR.py
@@ -87,33 +87,40 @@ def draw_ocr_box_txt(image, boxes, txts,
     for idx, (box, txt) in enumerate(zip(boxes, txts)):
         if scores is not None and scores[idx] < drop_score:
             continue
-        color = (random.randint(0, 255), random.randint(0, 255),
+
+        color = (random.randint(0, 255),
+                 random.randint(0, 255),
                  random.randint(0, 255))
         draw_left.polygon(box, fill=color)
-        draw_right.polygon(
-            [
-                box[0][0], box[0][1], box[1][0], box[1][1], box[2][0],
-                box[2][1], box[3][0], box[3][1]
-            ],
-            outline=color)
-        box_height = math.sqrt((box[0][0] - box[3][0])**2 + (box[0][1] - box[3][
-            1])**2)
-        box_width = math.sqrt((box[0][0] - box[1][0])**2 + (box[0][1] - box[1][
-            1])**2)
+        draw_right.polygon([box[0][0], box[0][1],
+                            box[1][0], box[1][1],
+                            box[2][0], box[2][1],
+                            box[3][0], box[3][1]],
+                           outline=color)
+
+        box_height = math.sqrt((box[0][0] - box[3][0])**2 \
+                               + (box[0][1] - box[3][1])**2)
+
+        box_width = math.sqrt((box[0][0] - box[1][0])**2 \
+                              + (box[0][1] - box[1][1])**2)
+
         if box_height > 2 * box_width:
             font_size = max(int(box_width * 0.9), 10)
-            font = ImageFont.truetype(font_path, font_size, encoding="utf-8")
+            font = ImageFont.truetype(font_path, font_size,
+                                      encoding="utf-8")
             cur_y = box[0][1]
             for c in txt:
                 char_size = font.getsize(c)
-                draw_right.text(
-                    (box[0][0] + 3, cur_y), c, fill=(0, 0, 0), font=font)
+                draw_right.text((box[0][0] + 3, cur_y), c,
+                                fill=(0, 0, 0), font=font)
                 cur_y += char_size[1]
         else:
             font_size = max(int(box_height * 0.8), 10)
-            font = ImageFont.truetype(font_path, font_size, encoding="utf-8")
-            draw_right.text(
-                [box[0][0], box[0][1]], txt, fill=(0, 0, 0), font=font)
+            font = ImageFont.truetype(font_path, font_size,
+                                      encoding="utf-8")
+            draw_right.text([box[0][0], box[0][1]], txt,
+                            fill=(0, 0, 0), font=font)
+
     img_left = Image.blend(image, img_left, 0.5)
     img_show = Image.new('RGB', (w * 2, h), (255, 255, 255))
     img_show.paste(img_left, (0, 0, w, h))
@@ -132,8 +139,7 @@ def visualize(image_path, boxes, rec_res):
 
     draw_img_save = Path("./inference_results/")
     if not draw_img_save.exists():
-        draw_img_save.mkdir(parents=True,
-                            exist_ok=True)
+        draw_img_save.mkdir(parents=True, exist_ok=True)
 
     image_save = str(draw_img_save / f'infer_{Path(image_path).name}')
     cv2.imwrite(image_save, draw_img[:, :, ::-1])
@@ -220,16 +226,16 @@ class TextSystem(object):
         dt_boxes, elapse = self.text_detector(img)
         print("dt_boxes num : {}, elapse : {}".format(
             len(dt_boxes), elapse))
-        if dt_boxes is None:
+        if dt_boxes is None or len(dt_boxes) < 1:
             return None, None
-        img_crop_list = []
-
         dt_boxes = self.sorted_boxes(dt_boxes)
 
+        img_crop_list = []
         for bno in range(len(dt_boxes)):
             tmp_box = copy.deepcopy(dt_boxes[bno])
             img_crop = self.get_rotate_crop_image(img, tmp_box)
             img_crop_list.append(img_crop)
+
         if self.use_angle_cls:
             img_crop_list, angle_list, elapse = self.text_classifier(
                 img_crop_list)
@@ -239,7 +245,7 @@ class TextSystem(object):
         rec_res, elapse = self.text_recognizer(img_crop_list)
         print("rec_res num  : {}, elapse : {}".format(
             len(rec_res), elapse))
-        # self.print_draw_crop_rec_res(img_crop_list, rec_res)
+
         filter_boxes, filter_rec_res = [], []
         for box, rec_reuslt in zip(dt_boxes, rec_res):
             text, score = rec_reuslt