Intent to Implement and ship: Immersive Audio Model and Formats (IAMF) decoding support

[Syed AbuTalib]

Contact emails

low...@google.com, tgui...@chromium.org

Explainer

https://github.com/SyedAbuTalib/iamf-explainer/blob/main/explainer.md

Specification

https://aomediacodec.github.io/iamf/latest-approved.html

Design docs

https://docs.google.com/document/d/1G4Km3hxEnXonvgiZo7got_DWIatBrpYbyzk3yIpaV6A/edit?usp=sharing&resourcekey=0-rS2fUcQM7tcKNDoQmk7Tmg

Summary

Adds support for decoding and playing back the Immersive Audio Model and Formats (IAMF) container within HTML media elements via Media Source Extensions (MSE). IAMF is an open, royalty-free spatial audio format that supports channel-based, scene-based, and object-based audio presentations. Supporting this standard allows web developers to deliver consistent, immersive 3D audio experiences across different devices without relying on proprietary formats or managing complex discrete audio channel routing in JavaScript.

Blink component

Blink>Media>Audio

Web Feature ID

Missing feature

Motivation

Currently, delivering high-quality, immersive 3D audio on the web relies heavily on proprietary formats (like Dolby Atmos) or complex custom JavaScript audio rendering. IAMF provides a standardized, royalty-free container that allows web developers to deliver rich, consistent spatial audio experiences across devices for use cases like gaming, AR/VR, and streaming media. Adding IAMF support to Chromium's media pipeline aligns with the open web ecosystem and ensures a baseline for spatial audio interoperability.

Risks

Interoperability and Compatibility

Low interoperability risk. IAMF is an open, royalty-free spatial audio format maintained by AOMedia. Initial support in Chromium focuses on IAMF streams backed by the Opus codec in MP4 containers delivered via Media Source Extensions (MSE). Support can be detected by existing web APIs such as canPlayType or media capabilities.

Gecko: No signal, https://github.com/mozilla/standards-positions/issues/1437

WebKit: No signal, https://github.com/WebKit/standards-positions/issues/700

Web developers: No signals, N/A

Other signals: Strong interest from external partners.

Debuggability

Exposed via chrome://media-internals and DevTools Media panel.

Will this feature be supported on all six Blink platforms (Windows, Mac, Linux, Chrome OS, Android, and Android WebView)?

Yes

Supported on all platforms where Chromium media audio decoding is supported.

Is this feature fully tested by web-platform-tests?

https://github.com/web-platform-tests/wpt/blob/master/media-source/mediasource-iamf-playback.html

https://wpt.fyi/results/media-source/mediasource-iamf-playback.html?label=experimental&label=master&aligned

Flag name on chrome://flags

None

Finch feature name

IamfAudioDecoding

Requires code in //chrome?

False

Tracking bug

https://crbug.com/535279329

Estimated milestones

Shipping on desktop 153

Shipping on Android 153

Shipping on WebView 153

Requesting approval to ship?

Yes.

[Alex Russell]

Hey Syed,

Sorry for the slow reply. Dan noticed this Intent from the mailing list, but also that it wasn't flagged in the API OWNERS review queue in chromestatus; perhaps because it didn't link to the feature?:

https://chromestatus.com/feature/5113656292540416?gate=6110241444986880

Jason: do you happen to know why that might have happened in this instance?

As for the content of the intent, I'm very excited to see IAMF coming to the web platform; thank you for making it happen.

I'm a little confused that the Status entry doesn't flag that we won't be able to deliver this feature to Chrome for iOS, given that we're limited by Quicktime there, which doesn't have IAMF IIRC?

Also, it's a bit surprising that we don't have any understanding of web developer interest noted. Presumably there are partners and publishers that are interested in this work. Are we able to either identify them, or have them weigh in here or in GitHub as potential adopters? Adding new formats to the web is an expensive thing to try to unwind, so it would be good to be sure this will be adopted if/when launched.

Best,

Alex

[Syed AbuTalib]

Hey Alex,

Thanks for taking the time to read my request! Apologies, I had forgotten to link to the chromestatusentry page, it was on the last line of the draft and I missed it. 

You are correct that this feature will not appear on iOS. I believed that not including a milestone number for iOS would suffice, but I can see how that is still confusing. I have now added a sentence to "Dev trials and iterate on design" > "Platform support explanation". Please let me know if there is a better place for this!

I was initially hesitant about listing the interested partners (they did not explicitly ask to be named), but currently LG and Samsung are interested in IAMF decoding for their TVs. For content streaming providers the main two are Netflix and YouTube. 

Also, I did NOT click the API Owners Draft Intent to Ship email as it did not appear I could edit any of the prefilled sections (I wanted to include more information and change the Subject line). I can click Post if that is the only way to start the API Owners review process.

Let me know if you have any more questions!

Thanks,

Syed AbuTalib

[Alex Russell]

Hey Syed,

Those are some big partners! Thanks for letting us know. LGTM1

Best,

Alex