Fraunhofer IIS, primary inventor of the xHE-AAC audio codec, has collaborated with Axiomatic Systems LLC, the developers of the Bento4 Media Packaging SDK, to add support for today’s most efficient streaming audio codec xHE-AAC.
Bento4 is a fast, modern, open source C++ toolkit for MP4, HLS and MPEG-DASH media workflows used by content providers worldwide to prepare encoded content for delivery to consumers. With support in the Bento4 packaging tool, Fraunhofer is further expanding the xHE-AAC ecosystem for VoD and Live content delivery.
xHE-AAC enables consumers to enjoy uninterrupted streaming with all types of content – such as movies, music, audiobooks or podcasts. xHE-AAC offers maximum coding efficiency with a usable bit rate range that spans from 12 kbit/s to 500 kbit/s and above for stereo services. This helps video and audio streaming providers to overcome audio bandwidth constraints and thereby facilitates an enhanced, more reliable consumer experience. Such efficiency is particularly crucial in emerging markets where 2G/3G networks still exist in significant numbers and wherever heavily congested 4G/5G networks in major cities are a common reality.
Created with adaptive streaming via DASH or HLS in mind, xHE-AAC delivers transparent quality under good network conditions and, when necessary, seamlessly switches to the bit rates and quality levels that a congested network can support. Audio bandwidth saved as a result of xHE-AAC’s efficiency can be used to improve the video quality.
One of the key features of xHE-AAC is the mandatory MPEG-D loudness and dynamic range control metadata. It allows service providers to embed content- and endpoint-specific metadata in the audio bit stream for transmission which can then be used on the playback side to achieve a consistent loudness level and optimal dynamic range for any playback device and environment. In a living room environment, a film can be enjoyed with the full dynamic range, the way that the mix was intended. The same film on a mobile device in a noisy environment might call for loudness management in order to be enjoyed with intelligible dialog. With MPEG-D metadata, a single stream meets the needs of both of these use cases — and everything in between.
xHE-AAC is the latest member of the MPEG AAC audio codec family. Fraunhofer played a substantial role in the development of xHE-AAC and the MPEG-D DRC standard. xHE-AAC is natively supported in the latest Apple, Android and Amazon operating systems and products, and Fraunhofer’s xHE-AAC implementation has recently been licensed to Microsoft. Professional xHE-AAC encoder software is available directly from Fraunhofer IIS or its streaming equipment partners. Fraunhofer is offering a web-based test service that developers and manufacturers can use to validate their implementations of the xHE-AAC® audio codec for compliance with MPEG standards. The service, which is available exclusively at https://test.xhe-aac.com, is free to use upon registration with Fraunhofer IIS and will test both encoders and decoders. xHE-AAC and MPEG-D DRC patents are included in the AAC patent licensing program administered by VIA Licensing at no additional cost.
Header image: © istock – Ryzhkov