Fix: Integer overflow in calculate_overlap_ratio (utils.py:248) a…

[albcunha]

…t paddleocr

What it does

Update calculate_overlap_ratio at utils.py to use numpy types and functions

Problem

calculate_overlap_ratio in paddlex/inference/pipelines/layout_parsing/utils.py triggers a RuntimeWarning: overflow encountered in scalar multiply at line 248:

inter_area = inter_width * inter_height

Root cause

The root cause is at lines 237-238:

bbox1 = np.array(bbox1)
bbox2 = np.array(bbox2)

np.array() without an explicit dtype preserves the input's original type. When bounding boxes come from detection models as int32 arrays, all subsequent arithmetic stays in int32, which maxes out at ~2.1 billion. Two moderately large bounding box dimensions multiplied together (e.g., 50000 × 50000 = 2.5 billion) exceed this limit, producing an overflow and incorrect overlap ratios.

Fix

Two changes in calculate_overlap_ratio:

1. Cast inputs to float64 — prevents overflow in all downstream arithmetic:

bbox1 = np.array(bbox1, dtype=np.float64)
bbox2 = np.array(bbox2, dtype=np.float64)

2. Use np.multiply with explicit dtype — belt-and-suspenders on the exact line that overflows:

inter_area = np.multiply(inter_width, inter_height, dtype=np.float64)

Why float64?

• float64 is numpy's default float type and supports values up to ~1.8×10³⁰⁸
• The function returns a floating-point ratio (0.0–1.0), and calculate_bbox_area already uses float internally — float64 keeps all arithmetic in one consistent type
• int64 would also prevent the overflow, but the intermediate values would be implicitly upcast to float at the division step anyway

Impact

This function is called by several other functions in the same module (_get_minbox_if_overlap_by_ratio, remove_overlap_blocks, shrink_supplement_region_bbox) and is imported directly by xycut_enhanced/xycuts.py via from ..utils import calculate_overlap_ratio. The fix is fully backward-compatible — the function signature, behavior, and return type are unchanged.

[paddle-bot]

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[albcunha]

This is a bug that is happening at paddleocr, when calling paddlex

[albcunha]

Monkey patch while the pr is checked:

from __future__ import annotations

import importlib
import logging
import shutil
from pathlib import Path
from typing import Any

logger = logging.getLogger(__name__)


# ===========================================================================
# Pre-import patches — must run BEFORE `from paddleocr import PPStructureV3`
# because that import transitively loads all paddlex submodules into memory.
# ===========================================================================

def _get_paddlex_dir() -> Path:
    spec = importlib.util.find_spec("paddlex")
    if spec and spec.submodule_search_locations:
        return Path(next(iter(spec.submodule_search_locations))).resolve()
    raise RuntimeError("Could not locate the paddlex package on sys.path")


_paddlex_dir = _get_paddlex_dir()

# --- Patch: fix integer overflow in calculate_overlap_ratio ---------------
# The original uses np.array(bbox) which preserves int dtypes; multiplying
# large int32/int64 widths × heights overflows at utils.py:248.
# We patch the source file directly because other modules (e.g. xycuts.py)
# import with `from ..utils import calculate_overlap_ratio`, binding to the
# function object — runtime monkey patching can't reach those references.
_layout_utils_path = (
    _paddlex_dir / "inference" / "pipelines" / "layout_parsing" / "utils.py"
)

_OVERFLOW_PATCHES = [
    (
        "    bbox1 = np.array(bbox1)\n    bbox2 = np.array(bbox2)",
        "    bbox1 = np.array(bbox1, dtype=np.float64)\n    bbox2 = np.array(bbox2, dtype=np.float64)",
    ),
    (
        "    inter_area = inter_width * inter_height",
        "    print('--------MONKEYPATCH!!!--------')\n    inter_area = np.multiply(inter_width, inter_height, dtype=np.float64)",
    ),
]

try:
    _utils_src = _layout_utils_path.read_text(encoding="utf-8")
    _patched = False
    for _orig, _fix in _OVERFLOW_PATCHES:
        if _orig in _utils_src:
            _utils_src = _utils_src.replace(_orig, _fix)
            _patched = True
    if _patched:
        _layout_utils_path.write_text(_utils_src, encoding="utf-8")
        # Remove stale bytecode so Python recompiles from the patched source
        _pyc_cache = _layout_utils_path.parent / "__pycache__"
        if _pyc_cache.is_dir():
            for _pyc in _pyc_cache.glob("utils.*.pyc"):
                _pyc.unlink(missing_ok=True)
        logger.info(
            "Patched PaddleX utils.py: calculate_overlap_ratio now uses float64 "
            "(int overflow fix)"
        )
    elif all(_fix in _utils_src for _, _fix in _OVERFLOW_PATCHES):
        logger.debug("PaddleX utils.py already patched (float64 overflow fix)")
except Exception as e:
    logger.warning(f"Failed to patch PaddleX utils.py for overflow fix: {e}")

# ===========================================================================
# Now safe to import paddleocr — patched files will be compiled fresh.
# ===========================================================================
from paddleocr import PPStructureV3  # noqa: E402
``

[luotao1]

Please submit the PR to the develop branch at first.