Deploying mbr playlist for adaptive-bit-rate streaming

For HTTP streaming on flash and ios devices, FMS in 4.5 provides a categorical workflow on device-network basis. This is very easy to configure and deploy. Adaptive bitrate streaming was long solved problem by FMS, but now it goes one step ahead by providing the users facility of targeting individual device’s capabilities and requirements and let configure the multiple individual mbr playlists specific to them.

For example, if someone has a wifi enabled i-phone or android based phone, supporting a max bandwidth of 64 kbps in some region.. there it is foolish to assume that user will be able to get a smooth stream experience if served with 720 kbps stream. One may argue that switching logic will be good enough to not to switch to the 720 kbps stream even if listed in the mbr playlist. So what’s the harm in just preparing a consolidated list.. Yes, this is true.. but presenting a 720 kbps stream in this case will be good enough to confuse the switching logic.. And one may observe the unnecessary switching glitches if just for a fraction of second your network improves.. I am no expert in -“how player’s switching logic works”, but presenting a bandwidth which is out-of-range of device-network capability in its mbr playlist may be a very good idea in case of HTTP like delivery system.

So in case of variant playlist (HLS) and f4m (HDS), you may generate multiple versions of them depending upon targeted device-network situation. And there can present only those bit-rate encoded streams that may fall in the target network range..

For example, if publisher is publishing 64, 100, 200, 350, 500, 1000, 1500 kbps streams.. then for the wifi devices one may present only 64, 100, 200 kbps bit-rate streams, for desktop devices can list 350, 500, 1000, 1500 kbps streams and for devices which are on a middle kind of network can be presented playlist with 200, 350, 500 kbps bit-rate streams mentioned.

How to deploy it in system:

It is very easy from one web application to identify the device from which the page is being accessed. Depending upon the same, you may present the URL of mbr playlist (variant playlist in case of ios and f4m in case of HDS).. To assist creating a MBR playlist, FMS 4.5 provides a configurator tool..

Posted on September 26, 2011, in Uncategorized. Bookmark the permalink. Leave a comment.

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