HTML and CSS Reference
files that could possibly be inefficient and re-optimize for a better user experience. A lot of this QOS is tied directly to
the “garbage in, garbage out” rule of video where you can only preserve quality of transcoded video files; you cannot
add to them after they've been manipulated for the worse. These analytics allow advertisers, content owners, and ad
servers to test real-world examples of how their content is performing.
Various video players are becoming more and more HTML5 compliant as more of the browser market and their
respective user base supports the HTML5 video tag. Companies such as YouTube, Vimeo, Brightcove, and others
do this by offering the HTML5 video while failing gracefully to a Flash or Silverlight experience as needed. Also,
companies such as Netflix and Hulu needing DRM protection rely on these plug-in technologies since there is no
streaming protection standard in the HTML5 video specification, but one is in the works. Some delivery formats I've
discussed such as HLS can use a token/key exchange from server to client to offer some sort of protection, but this
feature is supported only in Safari browsers as of yet.
As advertisers need to deploy ads to various video players, the IAB along with industry working groups have
developed a standard specification for delivering ad tags to publisher and network video players that is universal.
The specification is called VAST.
Video Ad Serving Template (VAST) is the universal tag delivery format for a video players. Currently in release 2.0 and
moving quickly into 3.0, VAST aims to ease the ad delivery requirements to all the various video players by creating a
universal definition for which all players can and should adhere. VAST allows for easy ad insertion in between video
content, also known as video preroll or in-stream video . The video player will reach out to the ad server via a URL
request, and the ad server will respond with valid XML markup. Listing 7-10 shows an example VAST response from a
dummy ad server.
Listing 7-10. VAST Example
<AdTitle>VAST 2.0 Instream Test</AdTitle>
<Description>VAST 2.0 Instream Test</Description>