Giving Silverlight Streaming a go

I’ve been in New Zealand since April undergoing the arduous process of changing my visa to a UK work permit. That’s another story but what’s important is that I wanted to capture some of the scenery on video while I was here, and I figured a cool way to present it would be in a Silverlight application on a website. I didn’t have a personal website yet, so I decided to create http://www.andrewmyhre.com.

A couple of weeks and 3 roadtrips later, I’ve got some footage and a Silverlight application. I cut the video up using VirtualDub and encoded it into .wmv using Expression Encoder, which I’m very impressed with. The video and music are a combined total of around 300mb, and while my current hosts offer a minimum 1gb storage space on their hosting server I wanted to try something new. At first I figured Azure would be good to have a go at, but while I was googling Silverlight hosting I came across this: Silverlight Streaming.

Silverlight Streaming is currently in free public beta, and the basic deal is this: register yourself an application account, upload your silverlight application (XAP will do) in a .zip file and any media assets it needs and you’re given a script you can plonk into a web page to present the Silverlight app. They provide up to 10gb storage and they won’t charge you for bandwidth use – sweet!

It took me a couple of attempts to work the thing out, because the documentation seems little vague. I’ll enumerate some of the idiosyncracies I’ve come across.

The way the service works, which took me a little while to work out, is that it hosts your Silverlight XAP file and any media assets it needs. It doesn’t host the website your Silverlight is contained in. It’s up to you to create your website on another web host and reference the Silverlight app. Furthermore you can’t reference the XAP as you would regularly using an <object> tag or the Silverlight .Net control, because all of the files in your Silverlight Streaming account are only accessible from the Silverlight Streaming servers. You’ll just get access denied errors if you try. So the Silverlight Streaming website provides a couple of ways to embed your Silverlight using JavaScript or an iframe, which from my point of view is fine. The HTML for both methods is provided on the page for your application (browse to Manage Applications and select the appropriate application on the next page).

Deploying your application is straight forward when you know how. Create a standard Silverlight project and build it. Now browse to the /ClientBin folder and zip the .xap file. This is the file you upload as the ‘application package’ file. You can optionally include a manifest.xml file which specifies some metadata about your .xap – stuff like Silverlight version, desired width/height and some other guff. Pretty clear why it needs to be specified but including it in your zip file is optional as you can create one manually in the Silverlight Streaming application manager.

When I built my Silverlight website I added the video files to a /Video folder within the host website, and I wanted the same structure in the hosted Silverlight Streaming application. Well it’s not that simple, because Silverlight Streaming doesn’t provide you with a nice RESTful file system API. It’s more like you are given a bucket for your application, and whatever you include in your Zip file gets placed in that bucket in the structure provided.

So I was able to create my structure by including all of the video files within the Zip in a /Video subfolder BUT the Zip file was ~300Mb, so what happens when I want to update the XAP file? I have to update the Zip file and re-upload the whole thing, which on my connection is a 2+ hour operation. This is because every time you upload an application package your whole application bucket is cleared and replaced with the contents of your Zip. So this is not the ideal method for uploading media. Fortunately, there is another method, detailed below, which works for videos. Unfortunately, other types of media, like mp3, wma, jpg etc MUST be uploaded in this way.

An alternative to including the media in the Zip file is to use the Manage Videos function in your Streaming account. Here you can upload individual video files one-by-one into their own seperate little buckets. It’s a matter of clicking Upload Video, Browse for the file on your hard-drive, click the Upload button. You’ll get a nice little progress bar to tell you how the upload is progressing. Once you’ve uploaded your videos, each one is given a unique URL which will be something like http://silverlight.services.live.com/[accountnumber]/[videoname]/video.wmv. This makes it pretty easy to reference the videos from within your silverlight application.

In my case, I have around 100 videos all numbered sequentially. In my silverlight application there’s a For loop which generates the array of filenames to access, so the above pattern works nicely.

I have a couple of little issues with the management interface so far. The nice thing about the application package upload process is that it takes the contents of a Zip file and extracts them to a bucket with the file structure intact. Nice! But why can’t I do this with videos? Or on the other hand, why do I have to upload the entire Zip again when I just update one file? Why can’t I have the option to UPDATE my files, i.e: overwrite anything existing and leave anything else on the server untouched? I either have to spend all day uploading each video one-by-one, or wait all day for a gigantic Zip file to upload. Guys, please, do something about this.

The other issue is regarding non-WMV file formats. While I’m free to upload video files to the service, what about other formats like mp3 and wma? My application is video clips with a seperate audio soundtrack, which I want to keep separate. The audio files are in WMA format there’s about 200Mb of them. But the only way to upload anything other than WMV is to include it in the application package Zip file! WHY?? To get around this issue I used Microsoft Expression Encoder to encode them as WMV with a blank video track – which added about 50% to the total file size. I then uploaded them individually just like all the other videos. I’m not at all happy with the situation but there’s currently nothing I can do about it, I just have to spend hours and hours uploading these things.

So it’s a mixed bag. YAY for free media hosting, that’s awesome. All they need to do is allow for uploading a single Zip with all your videos in it seperately from the application package, OR allow foran application package UPDATE option which preserves files on the server where they’re not included in the zip. Also if they added the same upload progress bar we get for videos to the application package upload, that’d be tops. My website should be online in a few days, once I’ve finished uploading everything. *sigh*