Open Source C PDF Generation Libraries

Cross-platform command-line tool for creation of PDF documents from scans/photos of pages in JPEG (.jpg) format and the lightest weight ANSI C library to put multiple JPEG files into one PDF file. You can add handwritten comments to PDF scans (over original images) with xournal: http://xournal.sourceforge.net/ It supports graphics tablets and saves comments to PDFs as vector data.

Vanilla.PDF is a modern, high-performance, open-source C++17 SDK designed for creating, editing, signing, and analyzing PDF documents across multiple platforms. It requires no external runtime dependencies, making it lightweight and ideal for embedding into desktop applications, servers, or automation pipelines. The SDK offers full cross-platform support including Windows, Linux, macOS, and Android, with builds available for major compilers and architectures. Vanilla.PDF supports advanced PDF features such as adding CMS (PKCS#7) digital signatures, modifying content streams and metadata, and working with encryption and permissions based on standard PDF security models. It includes tools for parsing PDF internals like cross-reference tables and objects, providing fine-grained document analysis capabilities. The project is unit-tested with continuous integration pipelines, supporting sanitizers for enhanced code quality and stability.

Reporting engine library written in C. Create one XML file and generate PDF, HTML, TXT, and CSV reports based on queries. Has support for MySQL, PostgreSQL, ODBC. Bindings for PHP, Java, Python.

FlyPDF is a shared object library (.so) which allows to generate PDF files without using any PDF library as dependency. You may use it for any kind of usage and modify it to suit your needs. FlyPDF has other advantages: high level functions.

PDFWriter latest release (4.5.12) includes support for fonts that contain Emojis. Notable examples for Emoji fonts are Windows Segoe UI emoji and Google Noto font. This means that writing text that include emojis will result in lovely colorful emojis, rather than black and white representations. PDFHummus is a fast and free PDF Writing, Parsing and Modification library.