This article examines why basic text extraction from PDFs often falls short when building Retrieval Augmented Generation (RAG) pipelines. It highlights how losing visual layout information results in lost semantic context, affecting model accuracy and retrieval performance. The author introduces the concept of two critical layers within a document: the physical layer involving raw character data and coordinates, and the logical layer that constructs meaning through structural elements like headings, tables, and multi-column layouts.
- Why standard text extraction limits RAG performance
- Understanding physical versus logical PDF layers
- The role of layout awareness in preserving semantic context
- Why standard text extraction limits RAG performance
- Understanding physical versus logical PDF layers
- The role of layout awareness in preserving semantic context
Docling is a tool that parses documents and exports them to desired formats like Markdown and JSON. It supports various document formats including PDF, DOCX, PPTX, Images, HTML, AsciiDoc, and Markdown.
A post discussing new techniques developed for parsing and searching PDFs, focusing on turning them into a hierarchical structure for RAG search. The approach involves dynamically generating chunks for searches, sending headers and sub-headers to the Language Model along with relevant chunks.
The llmsherpa project provides APIs to accelerate Large Language Model (LLM) projects. It includes features like LayoutPDFReader for PDF text parsing, smart chunking for vector search and Retrieval Augmented Generation, and table analysis. It is open-sourced under Apache 2.0 license.
