[Bug]: pdf law parsing error: IndexError: list index out of range

[nexussdad]

Is there an existing issue for the same bug?

• I have checked the existing issues.

Branch name

main

Commit ID

453c291

Other environment information

OS type: centos 7.6
method: docker compose

Actual behavior

parsing pdfs using law method, most succeeded but one failed.

check logs:

Traceback (most recent call last):
  File "/ragflow/rag/svr/task_executor.py", line 130, in build
    cks = chunker.chunk(row["name"], binary=binary, from_page=row["from_page"],
          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/ragflow/rag/app/laws.py", line 106, in chunk
    for txt, poss in pdf_parser(filename if not binary else binary,
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/ragflow/rag/app/laws.py", line 80, in __call__
    return [(b["text"], self._line_tag(b, zoomin))
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/ragflow/rag/app/laws.py", line 80, in <listcomp>
    return [(b["text"], self._line_tag(b, zoomin))
                        ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/ragflow/deepdoc/parser/pdf_parser.py", line 831, in _line_tag
    while bott * ZM > self.page_images[pn[-1] - 1].size[1]:
                      ~~~~~~~~~~~~~~~~^^^^^^^^^^^^
IndexError: list index out of range

Expected behavior

No response

Steps to reproduce

parsing pdfs using law method.

Additional information

No response

[KevinHuSh]

fixed.