FileOptimizer vs lrzip

FileOptimizer is a free Windows program that recompresses already-compressed files to reduce their size while retaining their format and behavior. It supports batch processing and accepts files through its interface or command line; optimization replaces them with optimized versions. The maker says it handles more than 600 file extensions and identifies types by examining file contents, regardless of extension. Listed formats include APNG, AVIF, BMP, BPG, DDS, DNG, GIF, HEIC, HEIF, ICO, J2C, J2K, JP2, JPEG, JPG, JXL, MNG, MPO, PCX, PNG, PSD, SVG, TGA, TIF, TIFF, and WEBP. By default, it removes extra metadata and keeps originals in the recycle bin. The program includes more than 90 third-party tools as plugins and supports command-line automation. It is provided under the GNU Affero General Public License, free for personal and commercial use without feature limits. The maker lists Windows XP through Windows 11 and Server 2022 among its requirements. Lossy options are also documented for PNG, JPEG, and GIF.

lrzip is a free GPL-2.0 command-line utility for compressing large files, usually above 10–50 MB. It first applies an extended rzip pass to reduce long-distance redundancy, then uses a backend such as LZMA, ZPAQ, LZO, GZIP, or BZIP2. Users can favor speed or smaller output, but not both simultaneously. Compression and decompression are heavily multithreaded, with CPU detection, and compression windows can use available RAM. Sliding mmap can exceed physical RAM but may be extremely slow. Encryption uses AES-256-GCM with PBKDF2-HMAC-SHA512 and HKDF; forgotten passwords cannot be recovered. The main program handles single files, while lrztar packages directories. It targets 64-bit Unix-like systems and supports macOS 10.5 or later from version 0.43. Building uses configure and make. Archive output is LRZ or TAR-compressed LRZ, with stable source releases on GitHub.