IAMF with 360 video for YouTube

[Vizaion]

Hello!
So I encoded IAMF into 360 video nicely (metadat seems to be right, used MP4Box) however when uploading to YouTube, the video is processed as flat - seems like YouTube doesn't allow IAMF with 360 videos (mp4). The audio is fine - it sounds spatial (I injected a 2nd order Ambix) however the video is flat. And if I upload the same video to with source audio (no IAMF) to YT - it's processed correctly, as a 360 video.
Before you ask - I checked the metadata on both files, and the video metadata doesn't seem to be different.

Why I want to have IAMF with 360 video? Because the 360 video was recorded with an addition of 2OA microphone and I wanted for peple to be able to distinguish audio change once they move the video (basuically not headlocked stereo.binaural), with different angles of the recording. How I can resolve it is I can downmix the recording to 1OA and mux it with video, however I wondered if it's possible to retain it in 2OA. I know there isn't that much of a difference on headphones anyway but it would be a cool feature if in future I could produce a 360 video with 3OA in IAMF.

For a reference, here are two videos I uploaded
https://youtu.be/StTOR8Mcd3E - 360 video with IAMF encoded (YT processes it as flat)
https://youtu.be/_WCUZNs7Oz4 - 360 source video, original audio (mono)

Let me know what's your experience and if there is a way to upload the 360 video with IMAF and make it work correctly - maybe it's just something that hasn't yet been implemeneted in YouTube. Or maybe there's an additioanl step, after muxing to make it 360 video recognizable.

Best,
Miko.

[jwcullen]

Yes, so your idea makes sense. 360 video + 3OA IAMF (or other orders) is possible as a format.

However, as far as I am aware, YouTube does not actually support the combination of 360 video and IAMF at this time.

[Vizaion]

That's a shame, I hope they will introduce it soon as they no longer support 1OA with 360 rendering any spatial audio with 360 videos useless. They really dropped the ball there, I hope they will push it with IAMF though.