improve codes comments

scripts/generate_meta_info.py

@@ -11,6 +11,7 @@ def main(args):
         for img_path in img_paths:
             status = True
             if args.check:
+                # read the image once for check, as some images may have errors
                 try:
                     img = cv2.imread(img_path)
                 except Exception as error:
@@ -20,6 +21,7 @@ def main(args):
                     status = False
                     print(f'Img is None: {img_path}')
             if status:
+                # get the relative path
                 img_name = os.path.relpath(img_path, root)
                 print(img_name)
                 txt_file.write(f'{img_name}\n')