• Composite Manifest Support for Rough Cut Editing scenarios in SSME by Vishal Sood
• New Composite Manifest support for building Rough Cut Editing (RCE) scenarios with Smooth Streaming by John Deutscher

I’ve been working with CSMs for three months now, so in this post I would like to share with you the lessons I’ve learnt during the process of creation and usage of the CSMs.

There are a few common mistakes and issues you might face during that process, so I hope this post will be helpful for the community.

“Error encountered on HEAD request to manifest uri <your manifest> for <position> clip in RCE manifest”

This will likely be the first issue you will encounter after trying to use a CSM. When using a CSM the Smooth Streaming Media Element (SSME) attempts to do a HEAD request on the manifest for each clip to make sure that the content hasn’t been moved (and if it has, it will used the new URL on the response).

There are two changes you have to make in order to fix this issue.

The first one is related to an existing known-issue on the applicationHost.config file of IIS. This server bug prevents the On-Demand smooth streaming handler from responding to HEAD request. To fix this go to the Smooth Streaming Readme page and check the Known Issues section, specifically the “Configuring the SmoothHandler handler mapping to process HTTP Head requests” item.

The second change must be done on the clientaccesspolicy.xml file, essentially to indicate that HEAD requests are allowed. To fix this make sure that your clientaccesspolicy.xml file includes http-methods=”*”or http-methods=”GET,HEAD,POST”:

<?xml version=”1.0″ encoding=”utf-8″?>
<access-policy>
  <cross-domain-access>
    <policy>
      <allow-from http-methods=”*” http-request-headers=”*”>     
        <domain uri=”*”/>
      </allow-from>     
      <grant-to>     
        <resource path=”/” include-subpaths=”true”/>
      </grant-to>     
    </policy>
  </cross-domain-access>
</access-policy>

“Caught exception trying to parse main manifest: V2 Manifest: Audio stream requires CodecPrivateData attribute”

This is because the CSM contains a clip that is referring a V1 Manifest, which is not a valid source for a CSM.

“Caught exception trying to parse main manifest: First video (audio) chunk in clip <position> [start time = <start time>, duration = <duration>] does not contain clip start position <clipStartPosition>”

This message indicates that the first chunk time + the first chunk duration of the reported stream is smaller or larger that the clip’s begin position. Therefore the first chunk time + the first chunk duration of the stream must contain the clip’s begin position.

“Caught exception trying to parse main manifest: Last video (audio) chunk in clip <position> [start time = <start time>, duration = <duration>] does not contain clip end position <clipEndPosition>”

This message indicates that the last chunk time + the last chunk duration of the reported stream is smaller or larger that the clip’s end position. Therefore the last chunk time + the last chunk duration of the stream must contain the clip’s end position.

Different Audio encoding settings in the CSM clips

If you have clips with different audio encoding settings, then the playback will suddenly stop. Due to a limitation on Silverlight, the audio settings have to be the same. The Silverlight pipeline is not able to handle audio property changes on the fly. So make sure that the audio of the clips are being encoded at same bit rate.

Sparse stream data within the clip

This will likely not cause any issue, but as today having sparse stream data within a clip is not supported I decided to include it on this list.

As you see, there are a couple of things to have in mind when creating and using composite stream manifests. I hope this post encourages you to use this amazing feature.

Happy streaming!

So, I started to dig and I came up with the following code:

// Live Streaming Section Path
const string LiveStreamingSectionPath = “system.webServer/media/liveStreaming“;
 
// Change this settings with your values
 
// Site name
string siteName = “Default Web Site“;
// Application name
string applicationName = “/SmoothStreaming“;
// Publishing point filename
string fileName = “LiveSmooth.isml“;
 
ServerManager serverManager = new ServerManager();
 
// Gets the site from IIS
Site site = serverManager.Sites[siteName];
 
// Gets the application from IIS
Application application = site.Applications[applicationName];
 
// Gets the LiveStreamingSection from the site configuration 
ConfigurationSection section = site.GetWebConfiguration().GetSection(LiveStreamingSectionPath);
 
// Gets the ConfigurationMethodInstance to get the available publishing points
ConfigurationMethodInstance instance = section.Methods["GetPublishingPoints"].CreateInstance();
 
// Sets the input parameters of the GetPublishingPoints method
instance.Input["siteName"] = site.Name;
instance.Input["virtualPath"] = applicationName;
 
// Executes the method
instance.Execute();
 
// Gets the PublishingPointCollection type.
Type type = Type.GetType("Microsoft.Web.Management.Media.LiveStreaming.PublishingPointCollection, Microsoft.Web.Management.Media.LiveStreaming“);
 
// Gets the PublishingPointCollection associated with the method output
ConfigurationElement collection = instance.Output.GetCollection(type);
 
// Gets an item from the collection using the Publishing Point fileName as parameter. 
// The item is of type PublishingPoint.
object pubPoint = collection.GetType()
                            .InvokeMember("Item“,
                                          BindingFlags.Public | BindingFlags.GetProperty | BindingFlags.Instance,
                                          null, collection, new object[] { fileName }, null);
 
// Invokes the desired method of the Publishing Point. 
// In this case we are calling the Start method (others supported functions are “Shutdown” and “Stop”)
pubPoint.GetType().InvokeMember("Start“,
                                BindingFlags.Instance | BindingFlags.Public | BindingFlags.InvokeMethod,
                                null, pubPoint, null);

Remember that in order to use the previous code, you must have references to the following assemblies:

• Microsoft.Web.Administration.dll (can be found at IIS Directory %windir%\System32\inetSrv)
• Microsoft.Web.Management.Media.LiveStreaming.dll (can be found in the GAC after installing the Live Smooth Streaming bits)

Hope this helps.

Happy streaming!

Now it’s time to share with you how to provide the rewind and fast forward options to enable a real rich video experience.

Again, adding support for these features is easy, and if you understood what we did for providing the Slow Motion experience, then the following will be a piece of cake.

For rewind, the trick is getting all the playback rates under 0.0 and for fast forward, all the playback rates above 1.0.

Show me the code!

Rewind

/// <summary>
/// Toogles the PlaybackRate of the Smooth Streaming Media Element.
/// Uses the PlaybackRates under 0.0 to support Rewind.
/// </summary>
public void OnRewind()
{
    // PlaybackRate index to set on the SSME.
    int newPlaybackRateIndex = 0;
    // Verify the state of the SmoothPlayer
    if (this.SmoothPlayer.CurrentState == SmoothStreamingMediaElementState.Paused
        || this.SmoothPlayer.CurrentState == SmoothStreamingMediaElementState.Playing
        || this.SmoothPlayer.CurrentState == SmoothStreamingMediaElementState.Buffering)
    {
        // Get the current PlaybackRate of the SSME
        double playbackRate = this.PlaybackRate;
        // The first time we get the Rewind PlaybackRates from
        // the SSME supported PlayBackRates. Rewind PlaybackRates 
        // are under 0.0
        if (this.rewindPlaybackRates == null)
        {
            this.rewindPlaybackRates = new List<double>();
            IList<double> supportedPlaybackRates = this.SmoothPlayer.SupportedPlaybackRates;
            for (int i = 0; i < supportedPlaybackRates.Count - 1; i++)
            {
                if (supportedPlaybackRates[i] < 0.0)
                {
                    this.rewindPlaybackRates.Add(supportedPlaybackRates[i]);
                }
            }
            this.rewindPlaybackRates.Add(1.0);
        }
        // Verify if the current PlaybackRate is within the 
        // allowables values. Get the index of the new 
        // PlaybackRate to set.
        if (playbackRate >= 0.0)
        {
            newPlaybackRateIndex = 0;
        }
        else
        {
            for (int i = 0; i < this.rewindPlaybackRates.Count - 1; i++)
            {
                if (this.rewindPlaybackRates[i] == playbackRate)
                {
                    newPlaybackRateIndex = (i + 1) % this.rewindPlaybackRates.Count;
                    break;
                }
            }
        }
        this.SmoothPlayer.SetPlaybackRate(this.rewindPlaybackRates[newPlaybackRateIndex]);
    }
}

Fast Forward

/// <summary>
/// Toogles the PlaybackRate of the Smooth Streaming Media Element.
/// Uses the PlaybackRates greather than 1.0 to support Fast forward.
/// </summary>
public void OnFastForward()
{
    // PlaybackRate index to set on the SSME.
    int newPlaybackRateIndex = 0;
    // Verify the state of the SmoothPlayer
    if (this.SmoothPlayer.CurrentState == SmoothStreamingMediaElementState.Paused
        || this.SmoothPlayer.CurrentState == SmoothStreamingMediaElementState.Playing
        || this.SmoothPlayer.CurrentState == SmoothStreamingMediaElementState.Buffering)
    {
        // Get the current PlaybackRate of the SSME
        double playbackRate = this.PlaybackRate;
        // The first time we get the Fast Forward PlaybackRates from
        // the SSME supported PlayBackRates. Fast Forward PlaybackRates 
        // are above 1.0
        if (this.fastForwardPlaybackRates == null)
        {
            this.fastForwardPlaybackRates = new List<double>();
            IList<double> supportedPlaybackRates = this.SmoothPlayer.SupportedPlaybackRates;
            for (int i = 0; i < supportedPlaybackRates.Count - 1; i++)
            {
                if (supportedPlaybackRates[i] > 1.0)
                {
                    this.fastForwardPlaybackRates.Add(supportedPlaybackRates[i]);
                }
            }
            this.fastForwardPlaybackRates.Add(1.0);
        }
        // Verify if the current PlaybackRate is within the 
        // allowables values. Get the index of the new 
        // PlaybackRate to set.
        if (playbackRate <= 1.0)
        {
            newPlaybackRateIndex = 0;
        }
        else
        {
            for (int i = 0; i < this.fastForwardPlaybackRates.Count - 1; i++)
            {
                if (this.fastForwardPlaybackRates[i] == playbackRate)
                {
                    newPlaybackRateIndex = (i + 1) % this.fastForwardPlaybackRates.Count;
                    break;
                }
            }
        }
        this.SmoothPlayer.SetPlaybackRate(this.fastForwardPlaybackRates[newPlaybackRateIndex]);
    }
}

For more information about the SSME Beta 2 release, check Vishal’s post : IIS Smooth Streaming Player Development Kit Beta 2 released

Enjoy it!

Also, in the efforts to bring the Smooth Streaming experience to everyone the IIS team published the IIS Smooth Streaming Player Development Kit 1.0 – Beta 1 which is intended to aid the development of rich Smooth Streaming experiences.

Bunch of posts to review if you are not aware of the new releases:

• IIS Media Services 3.0, including IIS Live Smooth Streaming, has been released – Chris Knowlton
• RTW of Live Smooth Streaming is now… Live. – John Bocharov
• IIS Media Services 3.0 and Player SDK released! – Alex Zambelli
• IIS Smooth Streaming Player Development Kit 1.0 – Beta 1 Released – Vishal Sood

I’m very excited with this release, as we have been using the Smooth Streaming Media Element almost from its beginning mainly for the work we did for the NBC Sunday Night Football event. (see here & here). I will start sharing with you how to take advantage of the SSME.

In this post I will show you how easy is to bring an Slow Motion experience using the SSME. Vishal blogged a great SSME getting started guide that I encourage you  to review before digging into the details of this post.

Adding support for Slow Motion to your Smooth Player is really easy, and basically what you have to do is getting the playback rates between 0.0 and 1.0, and move across them every time you click your Slow Motion button on the player.

Below you will find a code snippet ready to be used that will help you to implement the Slow Motion logic.

private List<double> slowMotionPlaybackRates;
/// <summary>
/// Toogles the PlaybackRate of the Smooth Streaming Media Element.
/// Uses the PlaybackRates between 0.0 and 1.0 to support Slow Motion.
/// </summary>
public void OnSlowMotion()
{
    // PlaybackRate index to set on the SSME.
    int newPlaybackRateIndex = 0;
    // Verify the state of the SmoothPlayer
    if (this.SmoothPlayer.CurrentState == MediaElementState.Paused
        || this.SmoothPlayer.CurrentState == MediaElementState.Playing
        || this.SmoothPlayer.CurrentState == MediaElementState.Buffering)
    {
        // Get the current PlaybackRate of the SSME
        double playbackRate = this.SmoothPlayer.PlaybackRate;
        // The first time we get the SlowMotion PlaybackRates from
        // the SSME supported PlayBackRates. SlowMotion PlaybackRates 
        // are between 0.0 and 1.0.
        if (this.slowMotionPlaybackRates == null)
        {
            this.slowMotionPlaybackRates = new List<double>();
            IList<double> supportedPlaybackRates = this.SmoothPlayer.SupportedPlaybackRates;
            for (int i = 0; i < supportedPlaybackRates.Count; i++)
            {
                if (supportedPlaybackRates[i] > 0.0 && supportedPlaybackRates[i] < 1.0)
                {
                    this.slowMotionPlaybackRates.Add(supportedPlaybackRates[i]);
                }
            }
            this.slowMotionPlaybackRates.Add(1.0);
        }
        // Verify if the current PlaybackRate is within the 
        // allowables values. Get the index of the new 
        // PlaybackRate to set.
        if (playbackRate <= 0.0 || playbackRate >= 1.0)
        {
            newPlaybackRateIndex = 0;
        }
        else
        {
            for (int i = 0; i < this.slowMotionPlaybackRates.Count; i++)
            {
                if (this.slowMotionPlaybackRates[i] == playbackRate)
                {
                    newPlaybackRateIndex = (i + 1) % this.slowMotionPlaybackRates.Count;
                    break;
                }
            }
        }
        this.SmoothPlayer.SetPlaybackRate(this.slowMotionPlaybackRates[newPlaybackRateIndex]);
    }
}

Hope you find the code snippet useful. Stay tuned!, new posts are coming.

PS: If you face any issue with the Smooth Streaming Development Kit or if you just want to provide feedback to the IIS team, please use this thread.

On September 26th, a new CodeCamp will take place at Buenos Aires. This year, I will join my teammate Diego Poza and together we will talk about how to develop composite applications for WPF & Silverlight using PRISM. Our presentation starts at 4:15 PM and will last 1 hour.

During the presentation we will go over PRISM Core Concepts and show a real-world implementation. Don’t miss the surprises at the end of the session.

On a related topic, Southworks is one of the sponsors of the event and several other southies will be presenting as well:

• Matias and Johnny will be presenting about Mega Datacenters with Windows Azure. Johnny will also join Zaiden and together they will present about VS 2010 and C# 4.0
• Martin Salias will be in functional mode explaining the main advantages of F#.
• Nico Paez will be talking about open source tools for .NET
• Beto, our IT Pro, will be off the charts. He will present in four sessions talking about Hyper-V, Windows Server 2008 R2 and SSME (SCOM, SCVMM, SCDPM).

Are you going to miss this amazing event? Register Now!

Where: Universidad de Palermo, Mario Bravo 1050, Buenos Aires

Time: From 9:30 AM to 19:00 PM

See you in the event and in the Southworks booth.

During the screencast we showed how the user experience can be enhanced by using the new capabilities of the Windows 7 Taskbar.

Thanks to Damian Schenkelman who helped us with the application.

Resources

• Screencast (in Spanish)
• Code
• Windows 7 Screencast – Taskbar, OverlayImage, ProgressBar, Thumbnails
• Developing applications with WPF and Windows 7 (Part I) 

Enjoy!

First, let’s take a look at the Live Smooth Streaming configuration settings window

The main idea here is to read the Live Streaming configuration section and get the attributes values from there. The piece of code looks like:

const string LiveStreamingSectionPath = “system.webServer/media/liveStreaming”;

ServerManager serverManager = new ServerManager();

Configuration configuration = serverManager.GetApplicationHostConfiguration();
ConfigurationSection section = configuration.GetSection(LiveStreamingSectionPath);

if (section != null)
{
    foreach (ConfigurationAttribute attribute in section.Attributes)
    {
        Console.WriteLine(“{0}: {1}”, attribute.Name, attribute.Value);
    }

    Console.ReadLine();
}

Running the preceding code will output the following:

As you see, reading the configuration settings is easy and can enable you different scenarios, for example, deleting the archived streams of a publishing point.
If you want to take a look at the Live Smooth Streaming schema, go to %windir%\System32\inetsrv\config\schema and open the IISMedia_LiveStreaming_schema.xml file.

Happy streaming!

One of the things that came up while spiking was finding a way to start, stop & shutdown a publishing point via code.

Microsoft.Web.Administration to the Rescue

With IIS7 a new API to administer IIS from managed code was introduced. This API is really simple to use and with a few lines of code you can manipulate the server configuration as any other information available in IIS7. (if you want to taste the power of this API, I recommend you to read this post from Carlos Aguilar Mares).

So, I used the Microsoft.Web.Administration.dll assembly, that can be found at IIS Directory (%windir%\System32\inetSrv), to perform the operations over the publishing point. But it was not so easy to do it, as there is no information available yet about what RSCA function has to be called  and which parameters need to be used in order get the desired results.

Then, I started to look at the different IIS configuration files (%windir%\System32\inetsrv\config) searching for clues and I came up with the Microsoft.Web.Management.Media.LiveStreaming.dll assembly (this assembly can be found in the GAC after installing the Live Smooth Streaming bits).

In that moment I summoned my best friend Reflector and together went to the depths of this assembly until we found some code that might be useful for our objective.

After doing some tests, I ended up with the following method:

private static void ExecuteRscaFunction(ConfigurationElement workerProcess,

                                        string siteName, string applicationPath,

                                        string fileName, string functionName)
{
    ConfigurationMethod configurationMethod = workerProcess.Methods["GetCustomData"];

    ConfigurationMethodInstance instance = configurationMethod.CreateInstance();
    instance.Input["guidIdOfFunctionCall"] = “Media_LiveStreaming_Control”;

    string currentLogicalPath = applicationPath;

    if (!currentLogicalPath.EndsWith(“/”, StringComparison.OrdinalIgnoreCase))
    {
        currentLogicalPath = currentLogicalPath + “/”;
    }

    string fullPath = string.Concat(currentLogicalPath, fileName);
    string parameters = string.Format(CultureInfo.InvariantCulture, “{0};{1};{2}”,
                                      functionName, siteName, fullPath);
    instance.Input["parametersOfFunctionCall"] = parameters;
    instance.Execute();
}

The most important thing of the method above is the functionName parameter. This parameter can be one the following values depending on what you want to accomplish:

• StartPublishingPoint. This is used to start a publishing point.
• StopPublishingPoint. This is used to stop the live source of the publishing point.
• ShutdownPublishingPoint. This is used to shutdown a publishing point.

To understand where the others parameters should come from, let’s take a look at the following example: So, if we want to the start the LiveSmoothStream publishing point associated to the SmoothStreaming application from the Default Web Site, we should call the ExecuteRscaFunction method in this way:

ExecuteRscaFunction(workerProcess,

                    “Default Web Site”, “/SmoothStreaming”,

                    “LiveSmoothStream.isml”, “StartPublishingPoint”);

The remaining parameter (workerProcess) must be retrieved from the application pool associated to the application.

Note: You can use the Microsoft.Web.Administration API to get all the values previously mentioned.

To see if the function is working you can add the following lines of code at the end of the method to parse the output and print it on the console.

string rawOutput = instance.Output["data"] as string;

byte[] bytes = Convert.FromBase64String(rawOutput);
ASCIIEncoding encoding = new ASCIIEncoding();

Console.WriteLine(encoding.GetString(bytes));

The output after executing the Stop, Shutdown and Start functions:

Hope this helps!. If you want to learn more about Smooth Streaming you might find useful the following links:

• IIS Smooth Streaming Technical Overview
• Smooth Streaming Architecture
• The Birth of Smooth Streaming
• Live Smooth Streaming for IIS 7.0 - Getting Started
• IIS Live Smooth Streaming - Creating and Managing Publishing Points
• Smooth Streaming Questions? We’ve Got Answers!
• I’ve seen the future and the future is… Smooth!
• A Brief History of Multi-Bitrate Streaming

Happy streaming!.

As Erwin said in this post, one of the breaking changes of this new drop is that they removed the .Silverlight and .Desktop extensions from the Assembly names. If you are like me and have more than one solution using Prism v2 with a bunch of projects, you will probably find really annoying going over each project to update the references and the xaml files.

So, in order to accomplish this, I created a Powershell script that will look for all the .csproj and .xaml that contain references to the old prism assemblies and will update it to the new version of them.

Note: If you have your code in TFS, make sure to go offline before running the script, so when you go back online it will detect the changes.

Disclaimer

This code is provided “AS IS” with no warranties, and confers no rights.

Download

You can find the script here.

Hope you find it useful.

During the latest months at Southworks, we have been working on several demos and materials for the Microsoft’s Professional Developer Conference 2008.

And in the last two weeks, with Matias and Edgardo, we were in Redmond (Microsoft Corp Main Campus) working hard with the Microsoft Developer & Platform Evangelism (DPE) Team on many different projects, all them related to PDC 2008.

Now is time to fly to LA. Matias, Edgardo, Tim, Alex, Johnny, Fede, and myself will be attending one of the biggest events designed for leading-edge developers and software architects.

There are a lot of sessions about many different topics, but the star will be the cloud. Microsoft will be announcing new technologies around the development platform, including the Windows Live Services Platform.

So if you are attending, let’s meet there. For sure that you will find me in the Cloud and Identity sessions.