Google Releases Lyra 1.3 For Advancing This Very Low Bitrate Audio Codec

In early 2021 Google announced Lyra as a very low bitrate codec intended for speech with aims of getting Lyra and AV1 possible for video chats on 56 kbps connections.

Months after the initial announcement they published the open-source code and have continued to advance it. Out this week is Lyra version 1.3 with their latest optimizations.

Lyra 1.3 improves this further beyond where they were with the Lyra 1.2 "V2" improvements in September. With Lyra 1.3 is now even better speed and reduced storage needs for the model.

The Lyra 1.3 TFLife-based model is said to be about 43% smaller than the prior release while also being around 20% faster compared to the prior v1.2 release. These wins are coming by using 8-bit integers rather than 32-bit floats for some weights and operations. The audio quality of Lyra 1.3 is said to be just as good as prior releases while enjoying the big speed-up. However, the Lyra bitstream has changed and is incompatible with prior releases due to the weight differences.

Downloads and more details on the Lyra 1.3 voice codec via GitHub.

Meanwhile Facebook/Meta recently announced EnCodec as their high fidelity neural audio compression technology with similar goals to Lyra.