Aaru.Compression.Native

This repository contains the Aaru.Compression.Native library for Aaru.

The purpose of this library is to provide compression and de-compression algorithms for Aaru.

No archiver processing code should fall here, those go in Aaru.Compression.

To build you just need Docker on Linux and run build.sh, that will generate a NuGet package for use with Aaru.Compression.

Currently implemented algorithms are:

General-purpose codecs

• Apple Data Compression (RLE with sliding dictionary created for Apple Disk Copy's NDIF)
• Apple LZH (LH1 variant used by Apple DART's "best" compression mode)
• Apple RLE (Run Length Encoding created for Apple DART)
• BZIP2
• FLAC
• KenCode (LZSS with variable-length prefix codes created for Apple Disk Copy's NDIF)
• LZ4
• LZFSE
• LZIP
• LZMA / LZMA2 / XZ
• LZO
• NDIF ShrinkWrap SIT2 (block Huffman LZSS from ShrinkWrap 3's Component Manager codec)
• Zstandard

Archive decompressors

• ACE v1 (LZ77) and v2 (blocked with delta/EXE/sound/picture modes)
• ARC methods 3–9 (pack, squeeze, crunch, squash) and PAK methods 10–11 (crush, distill)
• ARJ methods 1–4 and ARJZ (standard LZH and extended DEFLATE)
• Compact Pro (RLE, LZH+RLE)
• DiskDoubler (ADn LZSS, DDn block Huffman LZ77, adaptive Huffman, Stac LZS, Compact Pro, LZW)
• HA (ASC and HSC)
• LHA (LH1–LH7, LArc LZS/LZ5, PMarc PM1/PM2)
• RAR 1.5 (custom LZ77 with fixed Huffman tables)
• RAR 2.0 (block Huffman LZ77 with optional multichannel audio)
• RAR 3.0 (Huffman LZ77 / PPMd Variant H with VM-based post-filters)
• RAR 5.0 (Huffman LZ77 with native Delta/E8/E8E9/ARM filters)
• StuffIt classic methods 1–3, 5, 8, 13–15 (RLE, LZW, Huffman, LZAH, MW, LZSS, Arsenic)
• StuffIt X methods 0–4, 6 (Brimstone/PPMd, Cyanide/BWT, Darkhorse/LZSS, Deflate, Blend, Iron/BWT)
• StuffIt X preprocessors (English dictionary, x86 executable transform)
• ZIP methods 1–6, 9, 96–98 (Shrink, Reduce, Implode, Deflate64, WinZip JPEG, WavPack, PPMd)
• Zoo (LZD, LH5)

Each of these algorithms have a corresponding license, that can be found in their corresponding folder.

The resulting output of build.sh falls under the LGPL 2.1 license as stated in the LICENSE file.

Any new algorithm added should be under a license compatible with the LGPL 2.1 license to be accepted.

© 2021-2026 Natalia Portillo