LC3 (codec)

Last updated
LC3
Type of formatAudio
Extended toLC3plus
Standard Bluetooth 5.2 LE
LC3plus
Type of formatAudio
Standard ETSI TS 103 634

LC3 (Low Complexity Communication Codec) is an audio codec specified by the Bluetooth Special Interest Group (SIG) for the LE Audio audio protocol introduced in Bluetooth 5.2. [1] It's developed by Fraunhofer IIS and Ericsson as the successor of the SBC codec. [2]

Contents

LC3 provides higher audio quality and better Packet loss concealment than SBC, G.722 and Opus, according to subjective testing by the Bluetooth Special Interest Group and ETSI. [3] [4] [5] The conclusion regarding Opus is disputed as the test only included speech audio, but the comparison was made to version 1.1.4 of the reference Opus encoder, using complexity level 0 at 32 kbps and relying on CELT (general audio) instead of the FEC-capable SILK (speech); the test also did not take into account the newer version 1.2 of the Opus encoder released in 2017, where significant improvements were made to low bitrate streams. [5]

Supported systems:

LC3plus

LC3plus High Resolution mode is a codec defined by ETSI and is not compatible with the LC3 defined by Bluetooth SIG. [16] : 3  It's included in the 2019 DECT standard. [17]

On November 9, 2022, the Japan Audio Society (JAS) released a statement certifying LC3plus with the "Hi-Res AUDIO WIRELESS" logo. [18] LC3plus is the 4th codec to receive this, alongside SCL6 (formerly known as MQair), LDAC and LHDC codecs.

The ETSI implementation of LC3plus is source-available software, subject to a ETSI Intellectual Property Rights Policy and the usual patent restrictions. [19]

Fraunhofer defines a way to use LC3plus over A2DP.

See also

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References

  1. ↑ "LE Audio". Bluetooth Technology Website. Retrieved 2020-01-08.
  2. ↑ "LC3 / LC3plus". Fraunhofer IIS. Retrieved 2020-01-10.
  3. ↑ Frumusanu, Andrei. "CES 2020: Bluetooth SIG Announces LE Audio Standard: New Baseline For Next Decade". www.anandtech.com. Retrieved 2020-01-08.
  4. ↑ "New Bluetooth codec improves sound quality, benefits the hearing impaired". Android Authority. 2020-01-07. Retrieved 2020-01-08.
  5. 1 2 "Digital Enhanced Cordless Telecommunications (DECT); Study of Super Wideband Codec in DECT for narrowband, wideband and super-wideband audio communication including options of low delay audio connections (≤ 10 ms framing)" (PDF). ETSI. September 2018.
  6. ↑ "Android 13 may finally bring full support for Bluetooth LE Audio". xda-developers. 2021-12-22. Retrieved 2022-04-22.
  7. ↑ "Features and APIs Overview - Android 13 Developer Preview". Android Developers. Retrieved 2022-04-22.
  8. ↑ "New LC3 Encoder (I5f2f7627)". AOSP Gerrit. Retrieved 2022-04-22.
  9. ↑ "Add new LC3 decoder (I275ea8ba)". AOSP Gerrit. Retrieved 2022-04-22.
  10. ↑ "google/liblc3: Low Complexity Communication Codec (LC3)". GitHub. 26 June 2023. Retrieved 6 July 2023.
  11. ↑ Roth, Emma (2023-05-23). "Windows 11 adds support for Bluetooth's low-energy audio spec". The Verge. Retrieved 2023-05-25.
  12. ↑ Blog, Windows Experience; Woodman, Aaron (2023-05-23). "Announcing new Windows 11 innovation, with features for secure, efficient IT management and intuitive user experience". Windows Experience Blog. Retrieved 2023-05-25.
  13. ↑ "modules: Add zephyr lc3 codec by Casper-Bonde-Bose · Pull Request #44225 · zephyrproject-rtos/zephyr". GitHub. Retrieved 2022-04-24.
  14. ↑ "Bluez-alsa/SRC at master · arkq/Bluez-alsa". GitHub .
  15. ↑ "BlueZ » Blog Archive » LE Audio support in PipeWire".
  16. ↑ LC3plus High Resolution |Specification for use as vendor specific codec via Bluetooth A2DP (PDF), Fraunhofer Institute for Integrated Circuits IIS, 2021
  17. ↑ "LC3 / LC3plus: A plus in audio quality and transmission robustness for wireless accessories". Fraunhofer-Gesellschaft. Retrieved 2022-05-01.
  18. ↑ ""Hi-Res AUDIO WIRELESS" Two new codecs added to "Hi-Res AUDIO WIRELESS" logo's certified codecs" . Retrieved 9 November 2022.
  19. ↑ "marzzzello/LC3plus". GitHub . 29 June 2023.
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