Speex: Difference between revisions

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(Speex obsoleted by Opus. Category.)
 
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Speex is an Open Source/Free Software patent-free audio compression format designed for speech. The Speex Project aims to lower the barrier of entry for voice applications by providing a free alternative to expensive proprietary speech codecs. Moreover, Speex is well-adapted to Internet applications and provides useful features that are not present in most other codecs. Finally, Speex is part of the GNU Project and is available under the Xiph.org variant of the BSD license.
'''Speex''' is a legacy Open Source/Free Software patent-free audio [[codec]] designed for speech. It is obsoleted by [[Opus]].




==The Technology==
==Technical Information==


Speex is based on CELP and is designed to compress voice at bitrates ranging from 2 to 44 kbps. Some of Speex’s features include:
Speex is based on CELP and is designed to compress voice at bitrates ranging from 2 to 44 kbps. Some of Speex’s features include:
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* Discontinuous Transmission (DTX)
* Discontinuous Transmission (DTX)
* In-progress fixed-point port
* In-progress fixed-point port
* Echo Cancellation (experimental)
* Vorbis psychoacoustics model (experimental)


Note that Speex has a number of features that aren’t in other codecs such as [[Intensity stereo]] encoding, integration of multiple sampling rates in the same bitstream, and a VBR mode.
Note that Speex has a number of features that aren’t in other codecs such as [[Intensity stereo]] encoding, integration of multiple sampling rates in the same bitstream, and a VBR mode.


==References==
The above information was copied from the [http://www.speex.org Speex home page].


This information is copied from the [http://www.speex.org Speex home page]
[[Category: Codecs]]

Latest revision as of 21:28, 27 January 2022

Speex is a legacy Open Source/Free Software patent-free audio codec designed for speech. It is obsoleted by Opus.


Technical Information

Speex is based on CELP and is designed to compress voice at bitrates ranging from 2 to 44 kbps. Some of Speex’s features include:

  • Narrowband (8 kHz), wideband (16 kHz), and ultra-wideband (32 kHz) compression in the same bitstream
  • Intensity stereo encoding
  • Packet loss concealment
  • Variable bitrate operation (VBR)
  • Voice Activity Detection (VAD)
  • Discontinuous Transmission (DTX)
  • In-progress fixed-point port
  • Echo Cancellation (experimental)
  • Vorbis psychoacoustics model (experimental)

Note that Speex has a number of features that aren’t in other codecs such as Intensity stereo encoding, integration of multiple sampling rates in the same bitstream, and a VBR mode.

References

The above information was copied from the Speex home page.