# Speex: A Free Codec For Free Speech

arXiv: https://arxiv.org/abs/1602.08668 · HTML: https://mlsanity.com/paper/1602.08668/

## Key facts

- Cited by 6 papers in the map (data through 14 Oct 2026).
- First posted on arXiv 28 Feb 2016.

## Built on by (most cited first, 6 of 6)

- [Speech Resynthesis from Discrete Disentangled Self-Supervised Representations](https://mlsanity.com/paper/2104.00355/) (2021)
- [Towards Understanding and Mitigating Audio Adversarial Examples for Speaker Recognition](https://mlsanity.com/paper/2206.03393/) (2022)
- [Ultra-Low-Bitrate Speech Coding with Pretrained Transformers](https://mlsanity.com/paper/2207.02262/) (2022)
- [SEC4SR: A Security Analysis Platform for Speaker Recognition](https://mlsanity.com/paper/2109.01766/) (2021)
- [MFCCGAN: A Novel MFCC-Based Speech Synthesizer Using Adversarial Learning](https://mlsanity.com/paper/2306.12785/) (2023)
- [Fingerprinting Robot Movements via Acoustic Side Channel](https://mlsanity.com/paper/2209.10240/) (2022)

## Abstract (arXiv)

The Speex project has been started in 2002 to address the need for a free, open-source speech codec. Speex is based on the Code Excited Linear Prediction (CELP) algorithm and, unlike the previously existing Vorbis codec, is optimised for transmitting speech for low latency communication over an unreliable packet network. This paper presents an overview of Speex, the technology involved in it and how it can be used in applications. The most recent developments in Speex, such as the fixed-point port, acoustic echo cancellation and noise suppression are also addressed.