can not conver pdf file to word

[Intsigstephon]

请提供下述完整信息以便快速定位问题/Please provide the following information to quickly locate the problem

• 系统环境/System Environment：centos
• 版本号/Version：Paddle：develop PaddleOCR：2.6 问题相关组件/Related components：paddocr whl包。
• 运行指令/Command Code：

pdf测试文件

paddleocr --image_dir=ppstructure/recovery/UnrealText.pdf --type=structure --recovery=true --lang='en'

• 完整报错/Complete Error Message： File "/usr/local/python3.7.12/lib/python3.7/site-packages/paddleocr/paddleocr.py", line 615, in main image_file_list = get_image_file_list(args.image_dir) File "/usr/local/python3.7.12/lib/python3.7/site-packages/paddleocr/ppocr/utils/utility.py", line 60, in get_image_file_list raise Exception("not found any img file in {}".format(img_file)) Exception: not found any img file in ppstructure/recovery/UnrealText.pdf