Projects / Speex


Speex is a patent-free compression format designed especially for speech. It is specialized for voice communications at low bit-rates in the 2-45 kbps range. Possible applications include Voice over IP (VoIP), Internet audio streaming, audio books, and archiving of speech data (e.g. voice mail).

Operating Systems

Recent releases

  •  24 Jul 2008 11:29

    Release Notes: This release adds support for acoustic echo cancellation with multiple microphones and multiple loudspeakers. It also adds an API for decorrelating loudspeaker signals to improve multi-channel performance. A few bugs were fixed in the echo canceller, jitter buffer, and preprocessor. At this point, the API for 1.2 should be stable and only a few very minor additions are planned.

    •  04 Feb 2008 22:01

      Release Notes: The most obvious change in this release is that all the non-codec components (preprocessor, echo cancellation, and jitter buffer) have been moved to a new libspeexdsp library. Other changes include a new jitter buffer algorithm and resampler improvements/fixes. This is also the first release where libspeex can be built without any floating point support. To do this, the float compatibility API must be disabled (--disable-float-api or DISABLE_FLOAT_API) and the VBR feature must be disabled (--disable-vbr or DISABLE_VBR).

      •  24 May 2007 14:15

        Release Notes: The RAM requirement for wideband has gone down drastically (by more than two times). A new resampler module has been added, providing fast arbitrary sampling rate conversion. The echo canceller has also been improved. A bug in 1.2beta1 that made the echo canceller unstable has been fixed. The echo canceller should now converge faster, and should be robust and tolerant of incorrect capture-playback synchronization. The preprocessor has also been greatly improved. Not only should the quality be better, but it is now fully converted to fixed-point. At last, early TriMedia support (incomplete) has been merged.

        •  04 Sep 2006 17:27

          Release Notes: This release brings many significant improvements. The quality has been improved at the encoder and the decoder. This includes enhancer improvements, high-pass filters, and fixes for minor regressions in previous 1.1.x releases. Memory use has been greatly reduced (more than 50%), especially for fixed-point and narrowband. In general, CPU requirements have gone down and the Blackfin port has been sped up significantly. Non-codec improvements include an extension to the echo canceller API and a Speex-independent version of the jitter buffer. The echo canceller is also more robust.

          •  13 Mar 2006 06:12

            Release Notes: The main improvement in this release is that the echo canceller has now been converted to fixed-point arithmetic. The experimental Vorbis-based masking model (use --enable-vorbis-psy as an argument to the configure script) has also been improved and is now better and actually usable. Several other bugs have also been fixed.

            Recent comments

            03 Jun 2005 08:25 Sjobeck

            great stuff !
            Just some encouragement & some thanks.

            Great software.

            Keep up the great work.

            Peace. Love. Linux.


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