Lepton is a tool and file format for losslessly compressing JPEGs by an average of 22%.

Free Lossless Image Format

JPEG XL image format reference implementation

Free Lossless Audio Codec

JNI binding for Zstd

CD image processing suite with optimized lossless encoders in C#

Fast In-Memory Data Compression Algorithm (inline C/C++) 460+MB/s compress, 2800+MB/s decompress, ratio% better than LZ4, Snappy, and Zstd@-1

SimplE Lossless Audio

CharLS, a C++ JPEG-LS library implementation

🧙‍♂️ From developers to developers: a cross-platform tool for losslessly image compression.

Data Compression using Arithmetic Encoding in Python

JavaScript FLAC encoder, decoder

An online .txt file compressor, de-compressor tool which uses Huffman Coding for Lossless data compression.

An arithmetic coder for Rust.

High-speed lossless data compression of 16 to 512 bytes--get better average compression than QuickLZ for 512-byte blocks. td512 maintains good compression down to 16-byte blocks.

Java rewrite of Sela lossless audio codec

Delphi / Free Pascal Compitable JPEG-LS Codec

A streaming LZ predictor compression tool

🔧 Arithmetic coding algorithm implemented in Node.js, both API and CLI support. 算术编码 npm 包，支持 API 调用和 CLI。

compute entropy of an image, text; encode/decode text with huffman coding, LZW, LZ77; quantizatize image, signal