wxyhgk/retain-pdf

What it solves

RetainPDF is an open-source tool designed to translate PDF documents while preserving the original layout. It specifically targets the challenges of image-based or scanned PDFs, which are often difficult to translate without losing formatting, complex mathematical formulas, and multi-column layouts typical of scientific papers.

How it works

The project uses a proprietary font layout algorithm to restore the layout of multi-column papers and complex formulas. To avoid the fragmented translation often caused by translating text boxes individually, the system restores full semantic units (sentences and paragraphs) before translating them. It also includes features for PDF structure optimization, code protection to prevent mistranslation of code snippets, and a customizable translation strategy.

Who it’s for

Researchers, students, and professionals who need to translate academic papers (SCI papers), textbooks, and scanned documents while maintaining the exact visual structure and mathematical integrity of the original file.

Highlights

• Scanned PDF Support: Specifically optimized for image-based and scanned PDFs.
• Formula Preservation: High-stability preservation of inline formulas and their relationship with surrounding text.
• Layout Restoration: Advanced restoration of multi-column layouts and complex formatting.
• AI Assistant: Integrated AI Q&A that provides answers with page numbers and original text citations.
• Integrated Reader: Supports side-by-side comparison of original and translated PDFs, as well as PDF-to-Markdown reading.
• Open API: Provides an open API for automation and self-deployment via Docker.