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Embedded video and progressive download: A Quiz

I will provide you with two video files, video1.flv and video2.wmv, you need to embed them on the page and ensure that they use progressive download. Both video files are greater in size than 1GB so it will be obvious whether they are playing before they have completely downloaded. You will need to use the flash video player that I have provided for the flash video. Which one of the HTML snippets shown below should you use?

Snippet A

<object type="application/x-shockwave-flash" data="/player.swf" >
  <param name="movie" value="/player.swf"/>
  <param name="FlashVars" value="flv=/video1.flv"/>
</object>

<object type="video/x-ms-wmv">
  <param name="FileName" value="/video2.wmv"/>
</object>

Snippet B

<object type="application/x-shockwave-flash" data="/player.swf" >
  <param name="movie" value="/player.swf"/>
  <param name="FlashVars" value="flv=http://myserver.lshift.net/video1.flv"/>
</object>

<object type="video/x-ms-wmv">
  <param name="FileName" value="http://myserver.lshift.net/video2.wmv"/>
</object>

The answer is obviously B. Well actually not so obvious, hardly mentioned anywhere in fact, if you google for progressive download most of the pages would have been no help to you whatsoever! The Windows Media player and most flash video components switch between downloading the whole video file and downloading the file progressively based on the presence of the protocol string in the file name – if you have no http:// in your filename this probably means no progressive download for you.

Adobe is quite explicit in the documentation for their flex video player, here, if you scroll down a bit. I proved this empirically for Windows Media Player by watching the temporary internet files whilst downloading a 1GB WMV file, and seeing an additional mms stream appearing when snippet B was used indicating that IIS is streaming the file to the browser (and less technically the video had started playing but you could see it buffering whilst it downoaded more data).

by
tim
on
13/02/11
  1. George Langley
    on 15/06/11 at 6:54 pm

    Thanks for this info. (And yes, this was the first useful Google result! So thanks again!)
    Did your tests include both Windows Media Player on a Windows Browser/OS, AND the QuickTime Player with the Flip-4-Mac plugin on a Mac Browser/OS? Did using “http://…” enable progressive download on both platforms?
    Thanks.

 
 


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