GNU Ocrad vs PaddleOCR

GNU Ocrad is a free OCR program and library for Linux and self-hosted use. It reads PNG and PNM images and produces recognized text as 8-bit bytes or UTF-8. Its layout analyzer can separate columns and text blocks on printed pages. Ocrad runs as a standalone console application or as a backend for other programs. Documented options cover image transformations, layout detection, character recognition, text filters, and an OCR results file containing structured recognition details. The software uses ISO 10646 internally, with character-set selection through the --charset option. The manual recommends characters at least 20 pixels high and says 300 dpi scanning usually reaches a suitable size. It also notes sensitivity to character defects and difficulty adding recognition for new characters. The project describes Ocrad mainly as a research project, with algorithms that may change in later releases. Latest releases are available through GNU mirrors, while older and testing versions are hosted on Savannah.

PaddleOCR is an open-source OCR and document-processing toolkit for extracting text and structure from documents. Its PP-StructureV3 component turns complex PDFs and document images into Markdown and JSON while preserving their organization, and supports table extraction. PaddleOCR-VL handles multilingual document parsing across 109 languages, while PP-OCRv6 supports 50 languages in one model. PaddleOCR 3.0 also recognizes handwriting. For large document collections, PP-ChatOCRv4 extracts key information and integrates ERNIE 4.5. Models can be used online through the official website or called through an API; the official free API allows up to 20,000 pages of document parsing per day. Documentation describes local, C++, service, Android, iOS, and browser deployment options, among others. The license permits use, modification, distribution, and sale without restriction. SDK languages listed are Python, TypeScript, and Go. Support is available through GitHub Issues. One compatibility note: code written for PaddleOCR 2.x may not run with version 3.x.