AIR 2.6 for iOS and video playback

If you work with audio and video streaming, one of the worst limitation of AIR 2.6 for iOS is that it is not possible to stream video encoded in H.264 (and audio in AAC) inside your AIR application. AIR 2.6 for iOS supports NetConnection and NetStream but can decode only Spark, VP6, MP3, NellyMoser and Speex formats. So no H.264 and no AAC (don’t ask me why).

This is a real problem. Who is using today VP6 for video streaming or MP3 for audio ? On top of that, the performance of audio/video streaming is not perfect in AIR for mobile today (even for Android) especially because you have a lot of dropped frames and no frame interpolation, so delivery a stream in VP6 and MP3 for iOS devices is a very sub optimal solution that cannot compete with the very good native streaming capabilities of iOS to which the user is accustomed.

The AIR for iOS documentation mentions that it is possible to launch the native iOS video player pointing to an .mp4 (or .m3u8) video file, but this is not handy because the video is opened outside the AIR application and especially for iPad the user experience is really bad.

Fortunately there’s a sufficiently working solution to integrate in the AIR app the flowless experience of the native player: use the StageWebView object.

The StageWebView object  is a powerful way to integrate the elements that AIR is lacking today. Do you need a list with perfect scrolling ? AAC audio streaming ? H.264 streaming ? Well you can use a StageWebView to load “HTML5” code inside the AIR app and integrate this kind of content. Let’s do a simple example:

var webView = new StageWebView();
webView.stage = this.stage;
webView.viewPort = new Rectangle( 0, 0, stage.stageWidth, stage.stageHeight);
var path:String = new File(new File("app:/html/service.htm").nativePath).url;
webView.loadURL(Path);

This code will open a fullscreen instance of the native browser (without UI) and load a locally stored .html file (notice that it is necessary in iOS to use some hack like that at line 4 to obtain a valid url to access local html). Now you can easily understand that the best is to mix AIR UI and this windowed browser to exploit HTML5 capabilities especially for media streaming. A simple <video> tag inside the html code can do the job and offer perfect H.264 progressive and streaming playback to your AIR apps both in window and at fullscreen.

Communicate with StageWebView

It is not so easy to communicate with the page loaded inside the StageWebView. The object does not provide specifics API. Fortunately exist a class (StageWebViewBridge) developed to overcome the limitations of the standard StageWebView object. With StageWebViewBridge it is possible to communicate bidirectionally with the hosted html page and so create something similar to PhoneGap with Flash AIR.

Waiting for the future AIR 2.7 (which could have yet problems in the video area if it does not implement StageVideo in iOS) this is the best solution I found to overcome the limitations of AIR for iOS.