Universal.Common.IO.Compression 1.2.1

Universal.Common.IO.Compression

Compression codecs with no third-party package dependencies: Deflate, Gzip, Zlib, LZ4, LZMA (classic and Unity-header variants), and Zstandard.

Self-describing formats implement ICompressionAlgorithm. Deflate, Gzip, and Zlib also implement IStreamingCompressionAlgorithm. Raw LZ4 blocks implement ISizedCompressionAlgorithm because their uncompressed size is supplied separately.

Quickstart

// LZ4 (ISizedCompressionAlgorithm - raw block format needs the original size to decompress)
Lz4CompressionAlgorithm lz4 = new Lz4CompressionAlgorithm();
byte[] lz4Compressed = lz4.Compress(data);
byte[] lz4Restored = lz4.Decompress(lz4Compressed, data.Length);

// LZMA, Zstandard, Deflate, Gzip, Zlib
LzmaCompressionAlgorithm lzma = new LzmaCompressionAlgorithm();
byte[] lzmaCompressed = lzma.Compress(data);
byte[] lzmaRestored = lzma.Decompress(lzmaCompressed);

ZstdCompressionAlgorithm zstd = new ZstdCompressionAlgorithm();
byte[] restored2 = zstd.Decompress(zstdCompressedBytes);

IStreamingCompressionAlgorithm zlib = new ZlibCompressionAlgorithm();
using Stream decompressor = zlib.CreateDecompressionStream(compressedInput);
decompressor.CopyTo(output);
// For zlib, compressedInput is now positioned immediately after this member.

// Limit decompression to one member embedded in a larger stream.
using Stream member = zlib.CreateDecompressionStream(container, compressedLength, leaveOpen: true);
await member.CopyToAsync(output);

// End-to-end asynchronous helpers are available for every streaming codec.
await zlib.CompressAsync(input, compressedOutput, cancellationToken);
await zlib.DecompressAsync(compressedInput, output, cancellationToken);

Status

• LZ4, LZMA (+ Unity's own header variant): full encode and decode, verified byte-for-byte in both directions against independent real-world implementations (lz4js, Python's lzma module).
• Zstandard: full decoder (frame/block parsing, FSE with predefined or custom tables, Huffman-coded literals, sequence execution) - verified against real Zstandard-compressed data, including actual Figma-exported .fig files. The encoder currently emits valid, standards-compliant frames using Raw/RLE blocks only (real data any conforming decoder reads correctly, just not entropy-coded) - full FSE/Huffman encoding is its own follow-up.
• Deflate, Gzip, Zlib: synchronous and asynchronous streaming encode and decode. Zlib validates its header and Adler-32 checksum, supports non-seekable inputs, and leaves following members or container data unread.