Unlock full potential of Bluetooth® LE Audio with Ittiam LC3 Codecs

LE Audio: dawn of a new Bluetooth^® audio era

Bluetooth^® has become synonymous with audio over the years. It has touched our lives pervasively in varied product forms such as wireless headphones, handhelds and automotive infotainment systems to name a few. In early 2020, Bluetooth^® SIG with the intent of delivering next generation audio experience and innovative new applications to users, officially launched Bluetooth^® LE Audio. While building on the popular Bluetooth^® Low energy standard for low power devices, LE Audio has several key feature additions such as new Low Complexity communication codec (LC3), multi-stream audio, broadcast audio and hearing aid support.

In this article, we will take a look at LE Audio, the new LC3 Codec and its key benefits. The article will also describe ways in which Ittiam’s proven, production deployed LC3 codecs help powerplethora of new Bluetooth^® audio products, applications and services. These are all poised to significantly transform the way in which we experience and share audio with the world around us today.

A sneak peek into Bluetooth^® LE Audio

LE Audio, the next Generation Bluetooth^® Audio has several salient features (Figure 1). Let us unravel them one by one.

Multi-stream audio comprises of the transmission of multiple, independent, synchronized audio streams between an audio source device and one or more audio sink devices. Multi-stream will significantly improve performance of truly wireless earbuds (TWS) and will also facilitate smoother switching between multiple audio source devices.

Broadcast audio enables an audio source device to broadcast audio streams to unlimited number of Bluetooth^® audio sink devices. This further enables realization of a powerful and new innovative use case – Personal and Location-based audio sharing.

Personal audio sharing allows a user to share one’s audio experience with others around one – E.g., with family & friends.

Location-based audio sharing can help public venues such as airports, bars, gymnasiums, cinemas, and conference centers to share Bluetooth^® audio which augments the visitor experience.

Hearing aid support is high quality audio at significantly lower power along with support for Multi-stream and Broadcast Audio. It makes LE Audio an ideal choice for enabling new audio experiences and use cases for Hearing aid users.

Meet the new LC3 codec

At the heart of LE Audio updates is the new Low Complexity communication codec (LC3). LC3 is a flexible, high performance, low power audio codec which can deliver high quality audio even at lower bit rates. Finalized in sept-2020, LC3 is the mandatory codec for LE Audio and will be the key driving force behind new LE Audio products and allied use cases.

Highlights of LC3

• Compared to Bluetooth^®’s legacy SBC codec, LC3 can efficiently handle audio and speech with better audio quality, super wideband experience, low-latency and with lower power (Figure 2).
• Extensive listening tests carried out by Bluetooth^® SIG (Figure 3) show that, compared to SBC LC3 can deliver better/similar audio quality even at a 50% lower bit rate!
• The significant bit rate savings offered by LC3 translates to longer battery life and smaller form-factor products.
• With its inherent wide bit-rate range of operation, sampling rate and frame duration options, LC3 offers product developers high level of flexibility to ‘optimally’ deliver best possible audio experience under different operating conditions.

Path forward and challenges

Global annual audio streaming device shipment volumes are projected to grow rapidly over the next 5 years. A range of Bluetooth^® products including true wireless earbuds, smart speakers, wearables, wireless headphones, Bluetooth^® enabled hearing aids and automotive infotainment units are all set to incorporate LE Audio, and more specifically LC3 codec. Given the range of low-power devices which form key target segment for LE Audio, there is a clear need for highly optimized LC3 codec implementations to deliver LE Audio supporting end products with rich audio performance, high power-efficiency, extended battery operation and lower unit-cost.

Ittiam audio codec offerings

• For close to two decades, Ittiam has specialized in delivering highly optimized audio codecs with best-in-class audio performance and low power operation (extended battery life). With deployments in 100 Million+ devices across CE, smart living, wearables, automotive and broadcast market segments, Ittiam’s ready and proven audio IPs enable customers to deliver differentiated, high performance products with shorter time-to-market cycles and at reduced unit cost.
• Ittiam’s optimized audio codecs for ultra-low power have been licensed to multiple leading wearable brands (Ultra low power codecs for Smart wearables)
• Ittiam’s HEVC video decoder and Extended HE-AAC audio decoders power Android^TM AOSP multimedia experience (Optimized codecs for Android^TM)

• Ittiam’s highly optimized and proven LC3 codec for LE Audio are readily available to enable SoC companies, OEMs and System integrators realize full potential of LE Audio and to build differentiated products which can clearly stand out against competition.
• Ittiam’s fully standard compliant LC3 codecs have been licensed to leading SoC companies and have also been qualified by Bluetooth^® SIG (Bluetooth^® SIG Qualified design ID: 164005) enabling it to be incorporated into high end audio products displaying Bluetooth^® Logo.
• Ittiam’s LC3 codec has been integrated with leading Packetcraft, Inc.’s Bluetooth^® 5.2 stack demonstrating end-to-end LE Audio streaming use cases with low end-to-end latency and precise synchronized playback at sink(s) devices.

In addition to Ittiam’s off-the-shelf software IP offerings for video and audio, many customers also leverage Ittiam’s close to two decades of video and audio technology expertise in consulting in Multimedia technologies. Ittiam’s offerings for LE Audio includes off-the-shelf LC3 codec and consulting in Multimedia technologies for integrating LC3 codec with application software and Bluetooth^® stack to bring up LE Audio streaming use cases like Multi-stream and Broadcast audio, with key considerations for synchronized playback at multiple sink devices with low end-to-end latency.

Conclusion

LE Audio end products and use cases powered by the new LC3 codec will soon start rolling out in production volumes and are expected to grow at a rapid pace; significantly changing the way Audio content is consumed and experienced today over Bluetooth^®. With the insatiable and continuous demand from users for new gadgets with richer audio quality, higher power efficiency, longer battery operation and lower unit price, incorporating highly optimized and proven LC3 codecs will be a key differentiator for Bluetooth^® LE Audio end products and services.

Ittiam’s optimized LC3 codecs can be key enablers to power the Bluetooth^® LE-Audio revolution.