WinZip PDF Pro vs Zstandard

WinZip PDF Pro is a Windows application for editing, organizing, converting, signing, and protecting PDFs. Its editing tools add text, images, stamps, shapes, watermarks, files, and links, and can highlight or underline text. Page tools delete, rotate, reorder, and extract pages or split a PDF into new files. Conversion works between PDF and formats such as Word, Excel, PowerPoint, JPG, and PNG. Signatures may be drawn, typed, or uploaded as an image; documents can also be password-protected and assigned permissions. The maker says compression has no file-size limit and is processed locally, and the application works offline. A 7-day trial starts at installation without requiring email, a credit card, or registration. After it ends, reading PDFs remains free, but other features are locked. The Free PDF Reader plan is free and supports reading, searching text, and bookmarking pages indefinitely. The current version supports Windows 11, 10, 8, and 7. Minimum requirements include a 1.5 GHz processor, 2 GB memory, and 220 MB disk space.

Zstandard is a lossless compression algorithm for real-time workloads, with controls that let users shift compression speed and ratio in small increments. Its reference implementation includes a C library and a command-line utility that creates and decodes .zst, .gz, .xz, and .lz4 files. The format is stable and documented in RFC 8878; the implementation is available under BSD or GPLv2. For small, related samples, training can produce a data-specific dictionary to improve compression. The same dictionary must be present for both compression and decompression, and the samples need to be correlated; there is no universal dictionary. The project documents builds with Make, CMake, Meson, Visual Studio, Buck, and Bazel, plus installation using vcpkg and Conan. Community bindings and ports are listed for languages including Python, Rust, Java, C#, JavaScript, Go, PHP, and Swift. Zstandard is free, with a free plan, and supports Linux, Windows, and macOS.