In simple English
This program lets you view, edit, and convert PDF files on your computer. It reads PDF files, fills out forms, and reads text aloud. You can also turn scanned paper documents into searchable files using text recognition. It is completely free to download and use, and it costs nothing in money. Building it from source takes some technical setup and patience.
What it is
PDF4QT is a C++ (a programming language used for fast software) PDF (Portable Document Format, a file format for fixed-layout documents) engine and set of applications for Windows and Linux. It includes viewers, editors, diff tools, and command-line utilities built on the Qt (a cross-platform application framework) library.
What it is good for
Solo builders who need to inspect, modify, or process PDF files locally without relying on paid cloud services or proprietary software.
- Includes multiple ready-to-use desktop applications for viewing, editing, and comparing PDFs.
- Supports advanced features like digital signatures, form filling, OCR (optical character recognition, a way to turn images of text into real text), and text-to-speech.
- Permissive MIT licence allows free use in both open-source and commercial projects.
- Compiling from source requires installing multiple external tools and libraries like vcpkg and CMake.
- Pre-built binaries are limited to Windows, Arch Linux, Flatpak, and AppImage formats.
- Large C++ codebase can be complex to maintain or modify for non-C++ developers.
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git clone https://github.com/JakubMelka/PDF4QT cd PDF4QT cmake -B build -S . -DPDF4QT_INSTALL_QT_DEPENDENCIES=0 -DCMAKE_INSTALL_PREFIX='/' -DCMAKE_BUILD_TYPE=Release cmake --build build