Yesterday a student from my class ask me to help him solve a problem that was getting when testing Tom Krcha’s example files of his Multicast Streaming tutorial, the files he was using were the same included in Tom’s tutorial except for the Stratus Developer Key so after looking at the video tutorial included and testing the examples files You’ll get this error:

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Error: Error #2154: The NetStream Object is invalid.  This may be due to a failed NetConnection.
	at flash.net::NetStream/invoke()
	at flash.net::NetStream/attachCamera()
	at Broadcaster/setupStream()[C:\Users\Dave\Adobe Flash Builder 4\Broadcaster\src\Broadcaster.mxml:67]
	at Broadcaster/netStatus()[C:\Users\Dave\Adobe Flash Builder 4\Broadcaster\src\Broadcaster.mxml:50]

The error is pretty descriptive and what is saying is that was the NetStream was not getting the Camera signal or received a null value when trying to attach it.

The reason that this was happening is because in the NetStatusEvent Listener inside the switch statement we are using the event.info.code = “NetConnection.Connect.Success”; both for the Connection and the Stream

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netConnection.addEventListener(NetStatusEvent.NET_STATUS, netStatus);
stream.addEventListener(NetStatusEvent.NET_STATUS, netStatus);

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private function netStatus(event:NetStatusEvent):void{
	   writeText(event.info.code);
 
	   switch(event.info.code){
	            case "NetConnection.Connect.Success":
		    setupStream();
                    break;
		}
 
}

And on the setupStream() function we are trying to attach the camera and thats what throws the error cause we are using the “NetConnection.Connect.Success” to call this function.

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private function setupStream():void
{
      var groupspec:GroupSpecifier = new GroupSpecifier("myGroup/multicastOne");
      groupspec.serverChannelEnabled = true;
      groupspec.multicastEnabled = true;
 
      stream = new NetStream(netConnection,groupspec.groupspecWithAuthorizations());
      stream.addEventListener(NetStatusEvent.NET_STATUS, netStatus);
 
       var cam:Camera = Camera.getCamera();
 
       stream.attachCamera(cam);
       stream.publish("multicast");
 
	video.attachCamera(cam);
}

The fix is pretty straightforward all You have to do is include a case for the event.info.code: “NetStream.Connect.Success” and thats where we attach the camera to our stream.

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switch(event.info.code){
	case "NetConnection.Connect.Success":
	        setupStream();
	break;
	case "NetStream.Connect.Success":
	        var cam:Camera = Camera.getCamera();
	        stream.attachCamera(cam);
	        stream.publish("multicast");
	        video.attachCamera(cam);
	break;
}

And our setupStream() function will only define the GroupSpecifier and the NetStream:

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private function setupStream():void{	
	var groupspec:GroupSpecifier = new GroupSpecifier("myGroup/multicastOne");
	groupspec.serverChannelEnabled = true;
	groupspec.multicastEnabled = true;
 
	stream = new NetStream(netConnection,groupspec.groupspecWithAuthorizations());
	stream.addEventListener(NetStatusEvent.NET_STATUS, netStatus);
}

Attaching camera / microphone after NetStream is connected, prevents you from following:

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Error #2154: The NetStream Object is invalid. This may be due to a failed NetConnection.

Click here to open my example, or here to download the flex project.

You should see Your Broadcaster and your Receiver getting along just fine.

Step Number 1.-

First things first in order to play with Processing.js you’ll need to download and include it inside the tag of your html file.

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 <script src="script/js/processing-js/processing-0.9.6.min.js" type="text/javascript"><!--mce:0--></script>

Step Number 2.-

Now on the body tag You’ll need to open up a new canvas tag, and that’s where the processing.js will be running.

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You need a <a href="http://www.google.com/chrome" target="_blank">modern browser</a> to view this.

So what’s going on here ? You need to tell the canvas the location of the sketch that you’ll be running (in this case the worms.pjs file), in the datasrc attribute and a explaining text in case the user’s browser dont support HTML5 yet other way all they’ll see is a blank screen.

Step Number 3.-

The actual Processing.js that will display those playfull worms on Your HTML, if you’ve used Processing before you’ll notice that there’s actually nothing diffrent form what You do in a regular Processing sketch and if you copy and paste this in the Processing enviroment it will run as any other sketch.

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Mover[] movers = new Mover[30];
 
void setup() {
  size(viewportwidth,viewportheight);
  smooth();
  background(0);
  // Initializing all the elements of the array
  for (int i = 0; i < movers.length; i++) {
    movers[i] = new Mover(); 
  }
}
 
void draw() {
  noStroke();
  fill(10,0);
  rect(0,0,width,height);
 
  // Calling functions of all of the objects in the array.
  for (int i = 0; i < movers.length; i++) {
    movers[i].update();
    movers[i].checkEdges();
    movers[i].display(); 
  }
}
 
class Mover {
 
  PVector location;
  PVector velocity;
  PVector acceleration;
  float topspeed;
 
  Mover() {
    location = new PVector(random(width),random(height));
    velocity = new PVector(0,0);
    topspeed = 4;
  }
 
  void update() {
 
    // Our algorithm for calculating acceleration:
    PVector mouse = new PVector(mouseX,mouseY);
    PVector dir = PVector.sub(mouse,location);  // Find vector pointing towards mouse
    dir.normalize();     // Normalize
    dir.mult(0.5);       // Scale 
    acceleration = dir;  // Set to acceleration
 
    // Motion 101!  Velocity changes by acceleration.  Location changes by velocity.
    velocity.add(acceleration);
    velocity.limit(topspeed);
    location.add(velocity);
  }
 
  void display() {
    stroke(0);
    fill(175);
    ellipse(location.x,location.y,16,16);
  }
 
  void checkEdges() {
 
    if (location.x > width) {
      location.x = 0;
    } else if (location.x < 0) {
      location.x = width;
    }
 
    if (location.y > height) {
      location.y = 0;
    }  else if (location.y < 0) {
      location.y = height;
    }
 
  }
 
}

So that’s it You may open your html file in the browser and will see a nice animated wormy things chasing your mouse across the screen.

Hope this little explaings helps You get started with Processing.js, I’ll be doing a little more of experimentation with it myself and tell You how it goes.

Until next time See You.

Features

Easy configuration
Easily configure the standard functionality of Adobe® Flash® Media Playback. Control capabilities such as autoplay, autohide controls, poster frame definition, control bar positioning, and more — without the use of Adobe Flash authoring tools.

Custom look and feel
Completely replace each of the existing elements of the standard user interface with your own custom artwork.

Streamlined standard functionality
Eliminate duplicate efforts by leveraging the logic built into Flash Media Playback. Enjoy support for standard playback functions such as play/pause/stop, rewind, fast forward, DVR, multibitrate switching, and video navigation.

Integration of latest Adobe Flash Platform features
Enable quick integration of the latest Flash Platform features such as HTTP Dynamic Streaming and DVR functionality.

High-quality, multiprotocol support
Deliver the highest quality playback experience for the given bandwidth, detect and recover from error conditions, and improve overall user experience by working with the latest features of Adobe Flash Player 10.1 and Flash Media Server 3.5 software and HTTP Dynamic Streaming.

Open source file specifications
Achieve a live streaming experience using the MP4 fragment format, the industry standard for adaptive bitrate delivery, including open file format specifications for the media and manifest formats.

Plug-ins for advertising, analytics, and content delivery networks
Enhance your media player to monetize and track your content by utilizing plug-ins for advertising, analytics, and content delivery networks. Flash Media Playback allows you to load plug-ins hosted by partners dynamically, allowing your services to be upgraded without any changes to your website.

A year ago I started this blog more as an experiment that anything else in hopes that it will help me get in contact with fellow flashers and help the flash community as it had helped me, and now exactly one year latter the only thing that I can say is a big thanks for letting me be a little helpful and be part of such a great thing as is Flash today.

Thanks to Adobe for giving me the tools to do what I love and love what I do.
Thanks to you the readers who keep this little motor running and hope it will get more useful to you everyday .

THANKS !!!

Sincerely
Dave Gamez (.swfgeek)

Aral Balkan is Singularity.

A year is closing and a new one comes right away, my best wishes to all of you who read this blog, 2007 was a very exiting year for the Adobe Flash Platform, AIR development has prove to be here to stay with so many great projects and it’s not even out of the beta yet so I see a lot of great apps developed on AIR in 2008, Papervision 3D shown us that there’s no limit but our imagination and the effort we put in our projects , so the Flash Platform it’s going to keep growing in 2008 and growing fast, on a more personal level 2007 was great for me starting this blog back on March of 2007 was one of the best experiences I have ever had leading me to meet great developers designers and above all that great human beings, so keep tunned in because I have some serious plans for the for 2008, I’m starting to write the labs section of this site where I plan to post some examples on a regular basis and a tutorials section with more detailed explanation of how I do some of my work and be sure to keep a close eye because as time permits it I will be making a community site where we all can post and share our knowledge and our projects( If you’re interested in this project be sure to send me a mail).

Thanks to Adobe for letting me make a living of something I do for pleasure.
and at last but not at least thanks to all the readers and have a Great and Happy New Year 2008.

Thanks: Dave G?amez (.swfgeek)

Well I been kinda of busy lately, but I manage the time to give this site an Extreme Makeover, well not that much in fact the new theme of this blog wish is K2 it’s been developed very good it was just to easy to customize.
Hope to get the time to post some experiments with Papervision 3D that I’ve been making, well thats all for today hope you like the new look of this site.

Heres the link : www.davidgamez.com

I just installed snap shots witch by now I’m pretty shure you know how to use but just in case heres a little explaining:

This site called Snap Shots that enhances links with visual previews of the destination site, interactive excerpts of Wikipedia articles, MySpace profiles, IMDb profiles and Amazon products, display inline videos, RSS, MP3s, photos, stock charts and more.

Sometimes Snap Shots bring you the information you need, without your having to leave the site, while other times it lets you “look ahead,” before deciding if you want to follow a link or not.
In case it becomes annoying , just click the Options icon in the upper right corner of the Snap Shot and opt-out.

At least the lovely work of my wife is displayed on her website due to time and management issues the best option was to use wordpress so she can update frequently.

So don’t wait and go on and see some of her illustrations. ( the section of shop it’s not working right now we hope to update that soon ).

Here’s the link: www.cecymeade.com