Miracast*/Intel® WiDi Update: Dual Screen Apps

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The near-future ISV opportunities for Miracast continue to expand. What is really exciting are the ways ISVs are creating innovative dual-screen user experiences beyond simple monitor mirroring. A dual-screen application is one that supports using two screens for a user interface/experience. An example is a media player that uses a TV to play full screen video while leaving the video controls and the search/selection functions on the main screen. This resonates with users who are intrigued with the notion of projecting their content—photos, music, videos, web pages, applications, etc.—on their TVs. Intel has developed the Intel® WiDi Media Share app and Intel® WiDi Social Cast (a proof of concept with source code) for this purpose .

The Most Exciting Opportunity for Miracast Now

Intel believes that Miracast technology will become ubiquitous and that all devices will provide users the ability to cast content to nearby TVs. Miracast technology will be as common and used as often as sending a text message or checking social media updates. Several adjacent/competing technologies currently enable this, such as Apple Airplay*, Google Chromecast*, and most recently, Amazon Fire* TV. Unlike Miracast, none of these competing technologies are open industry standards, although they have “open” APIs for developers. Miracast is an open industry standard so any company can participate in the direction of the specification. As with all industry standards, it takes a little longer for competitive technologies to become interoperable. But, open industry standards tend to outlive point implementations. The number of corporations involved in Miracast underscores the adoption rate and demonstrates the importance of innovation desired by end users.

Intel® Wireless Display (Intel® WiDi) was released in January 2010. This proprietary specification was submitted to the Wi-Fi Alliance to kick off a new standard. It was peer reviewed and modified to eventually become the Wireless Display specification known as Miracast. In 2012, when the Miracast spec was released, Intel was the first to implement it in the Intel® Wireless Display. Intel understands that interoperability feeds this innovation of driving multiple displays from a single portable device. It will open up a completely new area in user experience design and will require the performance delivered by Intel® SOCs.

Intel has been working with a large number of ISVs who are developing dual screen applications. We expect dozens of new applications in media players, gaming, social media, and news delivery in 2014. The new interaction models are fresh and exciting, from the simple task of playing video on your TV to streaming aggregated personal content like social media, news, and music in vibrant TV-formatted and animated visualizations. 

ISVs Get Onboard with Dual Screen Apps

ISVs are starting to develop dual screen apps as a new way to engage the user with eye-popping experiences in content delivery—a way to differentiate applications in the highly competitive software download market. Details on how to implement dual-screen-aware applications can be found on the Intel Developer Zone website.

Miracast is supported directly by both Windows* 8.1 and Android* 4.2 and has a positive interoperability trend between CE, mobile, and PC devices. Beyond that, there are the dual screen functionality APIs in both operating systems and multiple programming environments. Join in this wave of user innovation and imagine how dual screen functionality can set your applications apart from the rest.

What's New for Windows 8.1

In Windows 8.1, Microsoft adopted Miracast as a new feature for the operating system, so now all Intel CPU-based systems will include Miracast. This is good news for ISVs as this broadens the total available market for ISVs developing dual-screen apps.

Modern App Support

Windows Store apps are now supported on multiple screens. In addition, dual-screen Store apps can now be written using a new Microsoft API called the Presentation API. Store apps can now occupy both screens, enabling all the dual-screen functionality that is supported in desktop mode. To find examples of this, search the Windows Store for Miracast. These APIs and source code are available on MSDN as well as Intel's dual screen application page on Intel’s Developer Zone (IDZ).

Miracast Connection API Update

Many ISVs were unhappy to find that the Intel WiDi connection API called the WEL (WiDi Extension Lib) was removed during the 8.1 integration. However, in Windows Threshold (Windows Next), a new connection API will be available directly from Microsoft, which will enable ISVs to create a seamless experience for users to connect to their Miracast receivers.

Android 4.4 Supports Dual-Screen Applications

Google has released an API that supports dual screen apps for Android. It is found under the Presentation Surface API and works with any combination of two screens including hardwired HDMI, display port, etc. Unlike Windows, this API is specifically an application-level feature, as there is no OS-level extended desktop in Android. Note that when the user turns “casting” on, they will see a duplicate view of the OS desktop on the TV.

Another important point is that Android is single-tasked. However, the Presentation Surface API can be called from a background "service" task, and an application can be written to spawn a service that keeps the second screen updated while other applications are used simultaneously. Since multi-tasking is highly rated among users, this becomes a very important feature.   

HTML 5.0

Intel drove the formation of the W3G working group to create a dual screen API that abstracts the connection technology for HTML 5.0. This working group holds most of its discussions on the public-webscreens (lists.w3.org/Archives/Public/public-webscreens/) mailing list. The discussion on the JavaScript* API is progressing, and there has been success in finding a common denominator API that covers Chromecast and Miracast. The current draft and proposal are here:

About the Author

Intel® WiDi Evangelist Steve Barile has been in the WiDi group since 2010, working with the Miracast wireless display standard from its inception at Intel. Since 2013, Steve has focused his time and expertise enabling the growing number of software vendors to develop dual-screen aware apps.

Windows 8.1 Reference and Resources

Android Resources

HTML5 Resources

Intel® WiDi Resources

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