SELA

SimplE Lossless Audio

A lossless audio codec which aims to be as simple as possible while still having good enough compression ratios.

Code Quality Metrics

Build Requirements

• cmake
• MSVC/GCC/CLANG/INTEL (Any compiler supporting C++11 should work)
• libao-dev (linux/bsd) / On windows you can skip this dependency

Current status

Task	Status
Encoder	DONE
Decoder	DONE
Reading and Writing WAV files	DONE
Reading and Writing SELA files	DONE
Multithreaded Encoding & Decoding	DONE
Player	DONE
Metadata support	TODO
Seektable support	TODO
Support for 24 bit audio	TODO
Optimization	TODO

Block Diagrams

To understand the core algorithm, see code in frame namespace, frame namespace utilizes maths which is implemented in lpc and rice namespaces.

References

• Linear Prediction
  • Wikipedia
  • Digital Signal Processing by John G. Proakis & Dimitris G. Monolakis
  • A detailed pdf
• Golomb-Rice lossless compression algorithm
  • Wikipedia
  • Here is an implementation
• FLAC overview
• Paper on shorten, the original open source lossless codec
• ISO/IEC 14496 Part 3, Subpart 11 (Audio Lossless Coding)

NOTE: You can get the legacy C code by switching to legacy branch.

Also, check out the Java version of this codec at https://github.com/sahaRatul/sela-java