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To save space, I removed the segments between 0 and 298, but you can see in this example that this format
separates the media into stream indices where the type is either video or audio. Again, you should be seeing a trend
here between the different delivery specifications because all of them rely on some form of instruction or manifest file.
Some campaigns may require smooth streaming to be used. it's normally a requirement for Microsoft video
advertising to Silverlight players, Windows phone 7, and Xbox gaming consoles.
As you can see from the previous examples, the fragmentation for delivering video over HTTP is growing pretty diverse
and competition is strong. As the open web world searches for a one-stop HTTP delivery solution that will appease all
platforms and browsers from Adobe, Microsoft, and Apple, the DASH promoters group ( ) is out to
do just that. Currently, the group is working on a standard in hopes of gaining adoption in the market and become a
ubiquitous solution across browsers and devices while using HTML5 video.
Meet MPEG-DASH. DASH stands for Dynamic Adaptive Streaming over HTTP. The group's work on this spec
started in 2010 in order to provide an agnostic delivery mechanism for audio and video that requires a standard
manifest file to deploy across firewalls and over straight HTTP. Adoption in the industry is growing strong from
companies such as Adobe, Akamai, Microsoft, and even device manufacturers such as Cisco and Samsung.
In 2012, Adobe and Akamai released an example of DASH working in the latest Flash Player at the NAB
conference, which gained a lot of interest from the industry, especially with intentions for HTML5 support. DASH uses
what is called a media presentation description , or an MPD manifest, to define its transport streams, much
like the earlier example manifest in HLS. The promise is that the DASH presentation file (MPD) will become the all-
encompassing solution for delivering all video in HTML5 browsers and devices, not just Flash Player.
Listing 7-7 shows an example of the DASH manifest file.
Listing 7-7. MPEG-DASH Example
<MPD type="static" xmlns="urn:mpeg:DASH:schema:MPD:2011" profiles="urn:mpeg:dash:profile:full:2011"
minBufferTime="PT1.2S" mediaPresentationDuration="PT0H2M59.23S">
<Title>MPEG-DASH Example</Title>
<Period start="PT0S" duration="PT0H2M59.23S">
<ContentComponent id="1" contentType="video"/>
<SegmentTemplate initialization="vid.mp4"/>
<Representation id="1" mimeType="video/mp4" codecs="avc1.64001f" width="1280" height="720"
startWithSAP="1" bandwidth="534520">
<SegmentTemplate timescale="1000" duration="9750" media="vid.mp4." startNumber="1"/>
<Representation id="2" mimeType="video/mp4" codecs="avc1.64001f" width="1280" height="720"
startWithSAP="1" bandwidth="812797">
<SegmentTemplate timescale="1000" duration="9750" media="vid.mp4" startNumber="1"/>
<Representation id="3" mimeType="video/mp4" codecs="avc1.64001f" width="1280" height="720"
startWithSAP="1" bandwidth="1607936">
<SegmentTemplate timescale="1000" duration="9750" media="vid.mp4" startNumber="1"/>
<Representation id="4" mimeType="video/mp4" codecs="avc1.64001f" width="1280" height="720"
startWithSAP="1" bandwidth="3088816">
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