请注意我们将在2018年11月23日进行例行的服务器维护工作。您可能会在当日48小时内被限制使用Audiokinetic网站和Wwise Launcher。

AURO-3D within the context of Wwise - A how-to blog!

空间音频 / Wwise 小贴士和工具

Picture2-1.png

Virtual Reality is quickly becoming the hottest production topic on the interactive audio scene. Audio for virtual reality offers a wealth of new design and implementation directions, and a wide range of unanswered questions and undiscovered territory. If you are at the beginning of a virtual reality project and have decided to use Wwise and AURO-3D for your pipeline, then these beginning steps should help you move past the starting line. 

First, let’s go over a few of the main topics.

In order to develop a full immersive experience, Virtual Reality requires audio that responds to movement and location in a 360 degree field. A common question on this topic might be “Isn’t that what surround sound accomplishes?” The short answer is no, it doesn’t.

What is 360 degree audio?

One way to think of 360 degree audio is to conceptualize stereo and surround sound playback in terms of dimensions.

Stereo sound playback is one-dimensional because it can be described mathematically as existing along the X axis. The X axis in this case represents a left to right line in front of the audience. A stereo mix offers the audience a “sweet spot” where the listener will receive the most accurate positional information.

Surround sound playback is two-dimensional because it can be described mathematically as existing along the X and the Y axis. The Y axis in this case represents a line which exists from the front to the back of the listening position. A Surround mix also offers the audience a “sweet spot” where the listener will receive the most accurate positional information.

360 degree audio is three-dimensional because it can be described mathematically as existing along the X, Y, and Z axis. The Z axis in this case represents a vertical line running from the bottom to the top of the audience listening field.

With the addition of head tracking in a Virtual Reality system, there is (theoretically) no sweet spot since the real-time mix will move relative to the location of the listener within the virtual space itself. This, of course, depends on the developer's ability to design and offer an audio field that responds correctly to the real time object based system in Wwise. This is where AURO-3D comes into the picture.

What is AURO-3D?

Without getting too deep into the details of the AURO-3D technology, please take a moment to go to their site and read over their approach to 360 degree audio

In relation to Wwise and game audio development, AURO-3D is the 360 library that will translate the real-time audio mix from Wwise into a real-time binaural mix. A binaural mix will offer the audience an audio experience that is closer to the way humans actually receive and interpret audio in the real world. Xavier Buffoni at Audiokinetic wrote a fantastic blog which will help you understand object based audio as it relates to a binaural mix and its routing scenarios. I suggest digesting it as soon as possible.

Please note that a real-time binaural mix like the one offered with the AURO-3D system is not the same thing as a binaural recording. A binaural recording has positional location and movement built into it, whereas we are discussing the objects within your interactive title being processed through a binaural mix system. A real-time binaural mix requires the interactive decisions of the audience, and cannot be premixed as would be the case with a binaural recording. That being said, if you are familiar with the binaural recording process and how it works, then you will have a head start on this topic.

Setting up Wwise and AURO-3D

AURO-3D for Wwise consists of two different components.

  • AURO Headphones
The AURO Headphones plug-in will create a real-time binaural mix of whichever multi-channel speaker setup you have designated on a Wwise Audio Bus in the Master-Mixer Hierarchy. When active, the plug-in will output a binaural mix to the left and right channels while all remaining speaker outputs will be muted. There is a PDF describing the details of the AURO Headphones plug-in, which can be opened from the context-sensitive help.
  • AURO Panner
The Panner plug-in can be considered a redundant tool at the moment, as the Wwise default panner will handle all of the same functions. We are currently recommending using the AURO Headphones plug-in and the Wwise default panner as the best 360 audio chain.

 

 Setting up AURO-3D with Wwise

  • Create a new Project and add the AURO Headphones presets.

Picture1-13.png 

  • Create a child Audio Bus under the Master Audio Bus.

 

Picture2-12.png

 

  • Select an AURO channel configuration in the General Settings tab of your new Audio Bus. The different configurations offer varied levels of detailed movement in the 360 field, and also demand a different amount of CPU as the speaker numbers increase. Spend some time analyzing and finding the best configuration for your title.

 

Picture3-7.png

 

Here is a breakdown of the different AURO channel (speaker) configurations

  •  which is a 5.1 surround system with 4 Height speakers

 

Picture4-4.png

  • which is a 5.1 surround system with 4 Height speakers and a Voice of God speaker

 

Picture5-5.png

  • which is a 5.1 surround system with 5 Height speakers and a Voice of God speaker

 

Picture6-6.png

  • which is a 7.1 surround system with 5 Height speakers and a Voice of God speaker

 

Picture7-4.png

An important note here is that the AURO system in Wwise will work with the ambisonic format. You can create another audio bus in the same way that you did for the AURO Headphones step and select one of the ambisonic channel orders.

Picture8-2.png

Ambisonic formats are really useful for Virtual Reality scenarios in that you can build assets that are already working in a static 360 degree field, as opposed to focusing your attention around mono files when it comes to ambiences. I have been recording and creating my own ambisonic files lately, and they can add a lot of depth to your design. If you are new to ambisonic files and concepts, then here is a great blog entry from Xavier Buffoni at Audiokinetic to help explain some of it.

  • Add the AURO Headphones plug-in to the Effects tab of your new Audio Bus.

Picture9-2.png

  • Assign your audio assets to the new AURO Audio Bus in the Output Bus section of the audio assets General Settings tab.

Picture10-2.png

  • Be sure to listen to your audio on headphones, so the Binaural output of the AURO Headphones plug-in will be heard.

Here are a few pointers on some of the main settings in the AURO Headphones.

  • The Bypass button in the AURO Headphones is really useful for A/B comparisons of the binaural effect. The AURO Headphones plug-in will also cause a few level changes to the 2-channel mix by its design. You can use the plug-in's “Bypass Offset” to match the Headphones effect level with the bypassed signal. This will be the best way to have a neutral A/B comparison.

 

  • Other than the Bypass Offset, I have found the default settings on the Level, ER Level, and LFE level to be best left as they are. Experiment with them, of course, but know that these settings are applied to the binaural effect and not the reverb of the Headphones plug-in.

 

  • The Speaker Dist creates a distance between the speaker and the listener. I suggest allowing your real-time mix from Wwise to control that relationship. If you A/B test with the plug-in in Bypass, you can find a neutral relationship between what the plug-in is doing and what Wwise is doing before being processed through the binaural effect.

 

  • Each of the settings found in the Room section of the plug-in deal with the size and dimensions of the binaural effect. The distance to the respective walls are set in meters which influence the delay-times for the early reflections. All 6 walls are positioned relative to the listener. To prevent unwanted room modal response, try to use unrelated and asymmetrical values for the walls' distances. The ranges for these settings are from 1 meter to 10 meters.

 

  • The Reverb settings in AURO Headphones are less flexible than the different Wwise Reverbs you may be used to working with. I suggest bypassing the AURO Headphones Reverb at the top of the plug-in window and using the Wwise RoomVerb, Wwise Matrix Reverb, Wwise Convolution Reverb, or iZotope Hybrid Reverb for your mix. Also, be sure to put your Reverb in the signal chain before reaching the AURO Headphones. No effects should be placed after the Binaural process that the Headphones plug-in creates.

 

You now have a basic knowledge of the setup and function of the AURO Headphones and AURO Panner plug-ins within the context of a Wwise session. There is a lot more to learn about the production of sound within this setup. Future blogs in this series will talk about designing and implementing audio for VR, as well as diving into ambisonic recording and encoding for use with this AURO-3D.

 

Tom Todia

Game Audio Designer

Engine Audio

Tom Todia

Game Audio Designer

Engine Audio

Tom is the Co-owner and an audio developer at Engine Audio, a game audio contract group. Tom has been in audio production for 20 years, and currently teaches audio for video games at Full Sail University.

 @EngineAudioTom

评论

Romain Loiseau

February 22, 2018 at 07:45 am

Very Interesting, but I just don't understand why my meters are not showing 10 channels when I'm using a auro 9.1 audiobus. Instead of L, R, C, LFE, HL, HR, HLS, HRS, I get L, R, C, SL, SR, BR, BL, LFE. Do you have an idea why ? thank you for this article,

Xavier Buffoni

April 04, 2018 at 10:58 am

I think you need to play content through this bus for the meter to adapt to the channel config.

留下回复

您的电子邮件地址将不会被公布。

更多文章

在Wwise 2017.1中使用 全新3D总线构架:模拟一个音频监控系统

27.7.2017 - 作者:内森 哈里斯(NATHAN HARRIS)

为什么游戏项目如此需要写Wwise插件

又及:我是怎么克服恐惧,真正爱上写插件的。 照片:这就是我,在自己家,挣扎于在虚拟现实 和“编程现实”间的。 引言...

18.10.2017 - 作者:罗伯特.班廷(ROBERT BANTIN)

动态早期反射的声源成像法

在我们的博客《在Unreal 中使用 Wwise Reflect模拟基于几何信息的动态早期反射》中,大家了解了如何用Unreal Integration和Wwise Audio...

9.1.2018 - 作者:塔丽•凯克里基安(THALIE KEKLIKIAN)

在Unity3D中助力你的声音设计师

27.3.2018 - 作者:比特里克斯.摩尔什(BEATRIX MOERSCH)

在Game Jams和微型项目中使用Wwise

从音频的角度上来看,Game...

10.7.2018 - 作者:约安.莫尔文(YOANN MORVAN)

借助 3D Meter 以视觉形式显示 Ambisonics 信息

Ambisonics 自 2016.1 版本起,Wwise 总线开始支持 Ambisonics 声道格式。Wwise 兼顾编码和解码过程:编码是指在 Ambisonics 总线中将非...

4.9.2018 - 作者:肖恩·索拉汉(SEAN SORAGHAN)

更多文章

在Wwise 2017.1中使用 全新3D总线构架:模拟一个音频监控系统

为什么游戏项目如此需要写Wwise插件

又及:我是怎么克服恐惧,真正爱上写插件的。 照片:这就是我,在自己家,挣扎于在虚拟现实 和“编程现实”间的。 引言...

动态早期反射的声源成像法

在我们的博客《在Unreal 中使用 Wwise Reflect模拟基于几何信息的动态早期反射》中,大家了解了如何用Unreal Integration和Wwise Audio...