Spatial audio makes 360º videos way more immersive, which is why a great audio experience has always been a priority for us. We support TBE audio for downloaded videos, and AmbiX for streamed videos. This is how it works:
- Download & install the free Facebook Spatial Workstation
- Open the FB360Encoder and load it with your spatial audio files
- Export your spatial audio as .tbe (48kHz) or .tbe (44.1kHz) and add it to your Project in Headjack
- Export your video using the YouTube Video (with 1st order ambiX) output format, or use an other tool to create a video with AmbiX audio according to the YouTube spatial audio specification and then add this video to your Project in Headjack
That’s all! Now, when your video is downloaded by a user, it will play the second-order TBE audio. If the user streams your video, the first-order AmbiX audio will play.
The reason we need two types of audio is that current video streaming protocols like HLS only support up to 8 channels of audio, and TBE has 10 channels, while second-order AmbiX has 9 channels. Therefore streaming of spatial audio is limited to first-order ambisonics.
iOS
Another thing to note is that streaming of spatial audio works on Android (Gear VR, Cardboard, Daydream, Oculus Go) and Windows (HTC VIVE, Oculus Rift), but does not work on iOS, until the Facebook Spatial Decoder plugin for iOS adds support for this. For now, we take the first channel of the AmbiX file, which contains all main audio data, and mix it down to mono on iOS. TBE does work on iOS when a user downloads a video to their device instead of streaming it.