Use spatial audio in 360-degree and VR videos

30/11/2019

You can experience a video's sound in all directions, just like real life, with YouTube spatial audio. Use it to take your 360° and virtual reality videos to the next level so that viewers can immerse themselves in your content. Learn how to upload 360-degree videos and virtual reality videos on YouTube.

Upload videos with spatial audio

  1. Create a 360° or VR video with spatial audio that meets the requirements below. 
  2. Run the latest version of the metadata tool on the video.
  3. Upload the video to YouTube.

​Preview spatial audio on VR videos

You can use the Resonance Audio Monitor VST plugin to preview the spatial audio of your VR videos before uploading them. The plugin works with any digital audio workstation that can render 4-6 channel audio files and host VST plugins.

Supported spatial audio formats

YouTube supports two different spatial audio formats:

  • First Order Ambisonics
  • First Order Ambisonics with Head-Locked Stereo

Spatial audio allows the sound a viewer hears to change as they move their head and look around in a 360° or VR video. This audio format is called First Order Ambisonics. On top of this, you can also add Head-Locked Stereo audio to your videos, which doesn’t change when a viewer moves their head. The Head-Locked Stereo audio track is often used for narration or background music.

Listening experience by device

Viewers can enjoy First Order Ambisonics audio on all devices. Viewers on a mobile device, or on Chrome or Opera web browsers, can also enjoy First Order Ambisonics with Head-Locked Stereo audio. For viewers on other web browsers, we’ll automatically down-mix the Head-Locked Stereo part of the audio, which may sound different.

Device specific details

Depending on the device, YouTube handles spatial audio in different ways.
 
Device Behavior
Mobile app YouTube decodes the Ambisonic soundtrack to binaural stereo using Head Related Transfer Functions (HRTFs)
Desktop Chrome and Opera  YouTube decodes the Ambisonic soundtrack to binaural stereo using Mid-Side (stereo) technique
Other browsers YouTube will down-mix the Head-Locked Stereo portion of the audio track to the omni-directional component (W) of the First Order Ambisonics

Technical requirements

You can see the full YouTube spatial audio spec to see all supported layouts and orderings, but make sure you follow these minimum requirements when using spatial audio.

Minimum requirements for spatial audio

  1. Metadata is added to your file.

  2. Only one audio track is used.

    • ​​Multiple audio tracks, such as tracks with spatial and stereo/mono audio in the same file, are not supported.

  3. Spatial audio uses Ambisonics (AmbiX) format:

    • ACN channel ordering
    • SN3D normalization

  4. Supported First Order Ambisonics (FOA) formats:

    • ​​W, Y, Z, X as a 4-channel audio track in your uploaded file

    • PCM encoded audio in a MOV container:

      • Sample rate: 48 kHz

    • AAC encoded audio in a MP4/MOV container:

      • Min. bitrate 256 kbps

      • sample rate: 48 kHz

  5. Supported First Order Ambisonics (FOA) with Head-Locked Stereo format:

    • W, Y, Z, X, L, R as a 6-channel audio track in your uploaded file

    • PCM encoded audio in a MOV container:

      • Sample rate: 48 kHz

* Nguồn: Youtube