BitmapData/draw() raises Security sandbox violation in Wowza 1.6, please help

Wowza Streaming Engine
1

Dear all,

I have Wowza 1.6 running on the same machine which hosts the swf client. I need to grab a frame from the flash video. The error I get is

SecurityError: Error #2123: Security sandbox violation: BitmapData.draw: http://localhost/testApp.swf cannot access unknown URL. No policy files granted access.

Why am I getting this error when both Wowza and the client are on the same machine? I have fiddled with crossdomain.xml and that has not helped. Furthermore the code works fine on Flash Media Server 3 and older versions of Wowza. What do I need to change in Wowza? I have set “StreamVideoSampleAccess” to * in conf/Application.xml and still no success.

I guess if I can figure out why it says “No policy files granted access.” then I can crack it.

Thanks

2

This is what works for me. You will need to struggle with it. I have found it to be a pain in the you know what.

Do the following:

  • Install the examples/FastPlayVideoStreaming example

  • Edit [install-dir]/conf/fastplay/Application.xml and change the Client/Access section to look like this:

    <Client>
	<IdleFrequency>-1</IdleFrequency>
	<Access>
		<StreamReadAccess>*</StreamReadAccess>
		<StreamWriteAccess>*</StreamWriteAccess>
		<StreamAudioSampleAccess>*</StreamAudioSampleAccess>
		<StreamVideoSampleAccess>*</StreamVideoSampleAccess>
		<SharedObjectReadAccess>*</SharedObjectReadAccess>
		<SharedObjectWriteAccess>*</SharedObjectWriteAccess>
	</Access>
</Client>

  • In Flash CS3 create a new ActionScript 3.0 movie and add a video object to the library then to the stage. Name it videoObj. Add a button to the stage and name it snapshotBut.

  • Add this ActionScript code:

    import flash.display.*;
import flash.utils.*;
import flash.geom.*;
import flash.media.*;
var nc:NetConnection = new NetConnection();
var ns:NetStream = null;
var snapshotTimer:Number = 0;
function ncOnStatus(infoObject:NetStatusEvent)
{
	trace("nc.onStatus: "+infoObject.info.code);
	if (infoObject.info.code == "NetConnection.Connect.Success")
	{
		ns = new NetStream(nc);
		var clientObj:Object = new Object();
		clientObj.nsOnStatus = function(infoObject:NetStatusEvent)
		{
			trace("ns.onStatus: "+infoObject.info.code);
		}	
  	
		clientObj.onMetaData = function(infoObject:Object)
		{
			trace("ns.onMetaData");
		}
  	
		clientObj.onPlayStatus = function(infoObject:Object)
		{
			trace("ns.onPlayStatus: "+infoObject.code);
		}
  	
		ns.client = clientObj;
		ns.addEventListener(NetStatusEvent.NET_STATUS, clientObj.nsOnStatus);
  	
		videoObj.attachNetStream(ns);
  	
		ns.play("Extremists");
	}
}
function takeSnapshot(event:MouseEvent)
{
	clearInterval(snapshotTimer);
  
	trace("takeSnapshot");
	var b:BitmapData = new BitmapData(640, 360); 
    b.draw(videoObj); 
  
	var mc:MovieClip = new MovieClip();
 	addChild(mc);
   	mc.graphics.beginBitmapFill(b, new Matrix(), true, true);
    mc.graphics.moveTo(0, 0);
    mc.graphics.lineTo(0, 360);
    mc.graphics.lineTo(640, 360);
    mc.graphics.lineTo(640, 0);
    mc.graphics.lineTo(0, 0);
    mc.graphics.endFill();
}
snapshotBut.addEventListener(MouseEvent.CLICK, takeSnapshot);
nc.addEventListener(NetStatusEvent.NET_STATUS, ncOnStatus);
nc.connect("rtmp://localhost/fastplay");

    This assume Wowza Pro is running on the same machine as Flash CS3.

    I really can’t support this. I am just leaving it as an example of what works for me. I have found this to be very hard to get working reliably. Even this example gives me scaling issues which I have spent hours trying to understand.

    Charlie

3

Thanks Charlie. It was actually one line of code in my app that was preventing the frame grab. Just before grabbing the frame the code was calling

videoObj.attachNetStream(null);

. Please note that I inherited the code from a developer who has left but I’m glad that I’ve finally tracked down the problem. Thanks again for taking your time to help.

Kind regards,

Ernie

4

Now,After 5 years.However, I encountered this problem either.

Thanks Charlie. According to his method, I solved the problem.

http://blog.vini123.com:slight_smile: