Spatial audio comes to the Cardboard SDK

Originally posted on Google Developers Blog

Posted by Nathan Martz, Product Manager, Google Cardboard

Human beings experience sound in all directions—like when a fire truck zooms by, or when an airplane is overhead. Starting today, the Cardboard SDKs for Unity and Android support spatial audio, so you can create equally immersive audio experiences in your virtual reality (VR) apps. All your users need is their smartphone, a regular pair of headphones, and a Google Cardboard viewer.

Sound the way you hear it

Many apps create simple versions of spatial audio—by playing sounds from the left and right in separate speakers. But with today’s SDK updates, your app can produce sound the same way humans actually hear it. For example:

• The SDK combines the physiology of a listener’s head with the positions of virtual sound sources to determine what users hear. For example: sounds that come from the right will reach a user’s left ear with a slight delay, and with fewer high frequency elements (which are normally dampened by the skull).


• The SDK lets you specify the size and material of your virtual environment, both of which contribute to the quality of a given sound. So you can make a conversation in a tight spaceship sound very different than one in a large, underground (and still virtual) cave.

Optimized for today’s smartphones

We built today’s updates with performance in mind, so adding spatial audio to your app has minimal impact on the primary CPU (where your app does most of its work). We achieve these results in a couple of ways:

• The SDK is optimized for mobile CPUs (e.g. SIMD instructions) and actually computes the audio in real-time on a separate thread, so most of the processing takes place outside of the primary CPU.


• The SDK allows you to control the fidelity of each sound. As a result, you can allocate more processing power to critical sounds, while de-emphasizing others.

Simple, native integrations

It’s really easy to get started with the SDK’s new audio features. Unity developers will find a comprehensive set of components for creating soundscapes on Android, iOS, Windows and OS X. And native Android developers will now have a simple Java API for simulating virtual sounds and environments.

Experience spatial audio in our sample app for developers

Check out our Android sample app (for developer reference only), browse the documentation on the Cardboard developers site, and start experimenting with spatial audio today. We’re excited to see (and hear) the new experiences you’ll create!

Android 5.1 Lollipop SDK

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By Jamal Eason, Product Manager, Android

Yesterday we announced Android 5.1, an updated version of the Android Lollipop platform that improves stability, provides better control of notifications, and increases performance. As a part of the Lollipop update, we are releasing the Android 5.1 SDK (API Level 22) which supports the new platform and lets you get started with developing and testing.

What's new in Android 5.1?

For developers, Android 5.1 introduces a small set of new APIs. A key API addition is support for multiple SIM cards, which is important for many regions where Android One phones are being adopted. Consumers of Android One devices will have more flexibility to switch between carriers and manage their network activities in the way that works best for them. Therefore you, as a developer, can create new app experiences that take advantage of this new feature.

In addition to the new consumer features, Android 5.1 also enhances enterprise features to better support the launch of Android for Work.

Android 5.1 supports multiple SIM cards on compatible devices like Android One.

Updates for the Android SDK

To get you started with Android 5.1, we have updated the Android SDK tools to support the new platform and its new APIs. The SDK now includes Android 5.1 emulator system images that you can use to test your apps and develop using the latest capabilities and APIs. You can update your SDK through the Android SDK Manager in Android Studio.

For details on the new developer APIs, take a look at the API Overview.

Coming to Nexus devices soon

Over the next few weeks, we’ll be rolling out updates for Android 5.1 to the following Nexus devices: Nexus 4, Nexus 5, Nexus 6, Nexus 7 [2012], Nexus 7 [2012] (3G), Nexus 7 (2013), Nexus 7 [2013] (3G/LTE), Nexus 9, Nexus 9 (LTE), Nexus 10, and Nexus Player.

Next Steps

As with all Android releases, it’s a good idea to test your apps on the new platform as soon as possible. You can get started today using Android 5.1 system images with the emulator that’s included in the SDK, or you can download an Android 5.1 Nexus image and flash the system image to your Nexus device.

If you have not had a chance to update your app to material design, or explore how your app might work on Android Wear, Android TV, or even Android Auto, now is a good time to get started with the Android 5.1 SDK update.

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