NuoYi

A simple tool to transform PDF and DOCX to Markdown.

中文文档

NuoYi uses marker-pdf for high-quality PDF conversion with OCR and layout detection. All processing is done fully offline after the initial model download.

Features

• PDF to Markdown: High-quality conversion using marker-pdf with surya OCR
• DOCX to Markdown: Native support for Microsoft Word documents
• Automatic GPU/CPU Selection: Detects available VRAM and falls back to CPU if needed
• Batch Processing: Convert entire directories of documents
• GUI Interface: PySide6-based graphical interface for easy batch conversion
• Image Extraction: Automatically extracts and saves images from PDFs
• Multi-language Support: 10 languages supported including Chinese, English, Japanese, French, Russian, German, Spanish, Portuguese, Italian, Korean

Installation

From PyPI

pip install nuoyi

With GUI support

pip install nuoyi[gui]

From source

git clone https://github.com/cycleuser/NuoYi.git
cd NuoYi
pip install -e .

Usage

Command Line Interface

# Convert a single PDF file
nuoyi paper.pdf

# Specify output file
nuoyi paper.pdf -o output/result.md

# Convert a DOCX file
nuoyi document.docx -o document.md

# Batch convert all files in a directory
nuoyi ./papers --batch

# Batch convert with custom output directory
nuoyi ./papers --batch -o ./output

# Force CPU mode (for low VRAM GPUs)
nuoyi paper.pdf --device cpu

# Force OCR even for digital PDFs
nuoyi paper.pdf --force-ocr

# Specify page range
nuoyi paper.pdf --page-range "0-5,10,15-20"

# Specify languages
nuoyi paper.pdf --langs "zh,en,ja"

GUI Mode

nuoyi --gui

The GUI provides:

• Directory selection for input/output
• File list with status tracking
• Device selection (auto/CPU/CUDA)
• Force OCR option
• Page range and language configuration
• Real-time progress and logging

Startup interface:

Select input directory:

Configure device and options:

Conversion result (viewed in VS Code):

Python API

from nuoyi import MarkerPDFConverter, DocxConverter

# Convert PDF
pdf_converter = MarkerPDFConverter(
    force_ocr=False,
    langs="zh,en",
    device="auto"  # or "cpu", "cuda", "mps"
)
markdown_text, images = pdf_converter.convert_file("input.pdf")

# Convert DOCX
docx_converter = DocxConverter()
markdown_text = docx_converter.convert_file("input.docx")

Supported Languages

Code	Language
zh	Chinese / 中文
en	English
ja	Japanese / 日本語
fr	French / Français
ru	Russian / Русский
de	German / Deutsch
es	Spanish / Español
pt	Portuguese / Português
it	Italian / Italiano
ko	Korean / 한국어

Use nuoyi --list-langs to see the full list. Default: zh,en.

Command Line Options

Option	Description
input	Input PDF/DOCX file or directory (with --batch)
-o, --output	Output file path (single file) or directory (batch mode)
--force-ocr	Force OCR even for digital PDFs with embedded text
--page-range	Page range to convert, e.g. '0-5,10,15-20'
--langs	Comma-separated languages (default: zh,en). See --list-langs
--list-langs	List all supported languages and exit
--batch	Process all PDF/DOCX files in the input directory
--device	Device for model inference: auto (default), cpu, cuda, or mps
--gui	Launch PySide6 GUI mode
-V, --version	Show version and exit

Memory Management

NuoYi automatically manages GPU memory:

• Auto mode (default): Detects available VRAM and uses GPU if sufficient (>6GB free)
• CPU mode: Forces CPU processing (slower but no VRAM limit)
• CUDA mode: Forces GPU processing (may OOM on large PDFs)
• MPS mode: For Apple Silicon Macs

If CUDA out of memory occurs during conversion, NuoYi automatically falls back to CPU.

Dependencies

Required

• marker-pdf>=1.0.0 - PDF conversion engine
• PyMuPDF>=1.23.0 - PDF page counting
• python-docx>=0.8.11 - DOCX conversion
• Pillow>=9.0.0 - Image processing

Optional

• PySide6>=6.5.0 - GUI support (install with pip install nuoyi[gui])

Model Download

Download Location

Models are downloaded automatically on first run and stored in:

~/.cache/huggingface/hub/

The models are from Hugging Face and include:

• vikp/surya_det - Layout detection model
• vikp/surya_rec - Text recognition model
• vikp/surya_order - Reading order model
• Other marker-pdf related models

Total size: approximately 2-3 GB.

For Users in China

Hugging Face may be blocked or slow in mainland China due to GFW. You can use a mirror:

# Set Hugging Face mirror (add to ~/.bashrc or run before nuoyi)
export HF_ENDPOINT=https://hf-mirror.com

# Then run nuoyi normally
nuoyi paper.pdf

Alternatively, you can download models manually and place them in the cache directory.

Custom Model Path

The current version does not support custom model paths to keep the tool simple and avoid configuration complexity. Models are always stored in the default Hugging Face cache location.

Notes

• After initial model download, everything works fully offline
• Use --device cpu if you encounter CUDA out of memory errors
• Legacy .doc format is not supported; convert to .docx first

License

GPL-3.0 License - see LICENSE for details.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Acknowledgments

• marker-pdf - The excellent PDF conversion engine
• surya - OCR and layout detection models