Home

packMP3 wiki

packMP3 is a lossless MP3 (MPEG Audio Layer III) recompressor. It re-encodes the Huffman-coded spectral data with an adaptive arithmetic coder and reconstructs the exact original MP3, bit for bit.

For installation, CLI usage, and the library API, see the README — this wiki covers the topics that don't fit there.

Pages

• FAQ — common questions (why does my file get rejected, is it really lossless, etc.)
• Format — the .pm3 archive format, the chunked (-k) container, version compatibility
• Benchmarks — packMP3 vs general-purpose compressors (gzip/bzip2/xz/zstd/brotli), and the -k ratio/speed trade-off
• Troubleshooting — warnings, error tolerance, -p/-d/-ver

Related projects

packMP3 is one of three sibling lossless recompressors sharing a common CLI convention:

• packJPG — JPEG
• packPNG — PNG
• packMP3 — MP3 (this project)