How to setup ambisonics playback in 4.19?

Hello,

I’m trying to test the new ambisonic playback functionality in 4.19 but so far I haven’t been able to get it to work. So far this is what I’ve tried:

  1. With the new audio engine enabled, I created a new project, enabled the Oculus Audio plugin (restarted) and Imported a 4 channel b-format audio file (had to convert it to 16 bits first since 24 is not supported).
  2. In the sound wave asset settings, I checked “isAmbisonics”
  3. Under Sound Submix I created a new submix and in it I set the “Ambisonics Plugin Settings” with a new Oculus Ambisonics Settings and set the channel format to Ambisonics.
  4. Dropper the file in the scene and played

The result is that the audio file plays but it’s not decoding. Removing the Sound Submix asset doesn’t make a difference. What am I missing? I also tried adding an Attenuation asset but I also couldn’t hear a difference.

Thank you.

You need to set Oculus as the spatialization plugin to use in the project settings for the platform. It’s a little confusing since we support different plugins for different audio engine effects. e.g. you could use Oculus on PC, Resonance on Android, and Steam Audio for Mac or something with the same project, so there needs to be a way to specify that.

This is an issue for lots of people so we’re considering ways to maybe do an auto-discovery and use the project settings as an override or something.

Thank you very much Minus_Kelvin. Yes, I knew there had to be a plugin selection setting somewhere but I was expecting to find it under Audio settings. It does make sense that it is be a platform specific setting, though.

I selected Oculus Audio under Platforms/Windows/Spatialization Plugin but still I can’t hear the ambisonic decoding and it doesn’t seem to make a difference what I choose there. Should this setting work for PIE too? I’m running UE4 on Windows 10.

Hi VirtualHC!

In order to use Ambisonics with Oculus, you’ll need to designate a Submix and how you want to handle the ambisonics file in the mix.

So create a Sound Submix for your Ambisonics file to output to and then you’ll want to create a Ambisonics Setting Asset which you will apply to that submix. Both of these are assets, so let me know if you need help creating them or assigning things.

Hi Dan,

Thank you for your reply. After setting things up again I seem to now get properly decoded ambisonics. The only issue I’m facing is that camera rotation doesn’t rotate the soundfield and acoustic orientation remains fixed. Non ambisonic sounds are being localized properly (and sounding great with Oculus’ near-field effect!).

For Oculus Audio, would it be ovrAudio_SetAmbisonicOrientation (in OVR_Audio.h) that needs to be called with the camera rotation? A quick search throughout the 4.19 source seems to show that this is not being called from anywhere.

binding oculus rift ambisonics sdk, and just access the vst parameters via source code. linking it to your codebase in unreal engine

What are the requirements for the source? For example, should it just be a 4channel .wav file, encoded as ambix or fuma? In the release notes it says it needs that tag in the file name so would that be, for example, AMB_BED_Forest_Day_AmbiX.wav?
Is there anything else the source file should adhere to to ensure it plays back properly within UE4?
Thanks!

4 channel wav file (16 bit) with AmbiX or FuMa in the file name. Here are my test files as an example:

ambisoncis_test_files_names.PNG

Hi Dan,

I would be very grateful if you could explain the creation and assignment in a bit more detail please. Or maybe point me in the direction of a step-by-step. I’m trying to get an ambisonics audio file working correctly in UE4.19.2 and it’s at the submix and assignment stage where I’m getting lost.

Thanks in advance!

The submix asset is only available if the audiomixer is enabled. to do this you can find instructions on how to do this here: https://valvesoftware.github.io/steam-audio/doc/phonon_unreal.html#enabling-audio-mixer-functionality

I face the same issue with both Oculus and Steam Audio plugins. I have done everything mentioned in this thread to no avail… My wav file is 4-ch AmbiX. UE 4.22.3. With the same setup and a mono wav file binaural seems to work fine, following the eyes view.

Hi there, I followed your instructions and am stuck at the same point : the sound seems to be spatialized but doesn’t rotate as the HMD do. How to do this ?
Actually trying with an Oculus Go Headset on 4.23.