SmoothFlow Deployment : Creating On-Demand Assets : Create AssetDescription.dat File for On-Demand Assets

Create AssetDescription.dat File for On-Demand Assets
Along with the bitrate profiles, you must pre-stage to Media Flow Controller an Asset Description file, as a simple text file (ASCII, with the "dat" extension), in the format given below. The Asset Description file does not need to be located with the bitrate profiles (it tells Media Flow Controller where they are) but must be located in the origin server configured in the namespace you intend to use.
Asset Description file format example, variables are underlined; options given below.
Version:1.0.4
Profiles:4
Frame Rate:24
KeyFrameInterval:2
Sequence duration:664
Profile_1:250
Profile_2:500
Profile_3:750
Profile_4:1000
URI: http://media.example.com/foo_p01.flv
URI: http://media.example.com/foo_p02.flv
URI: http://media.example.com/foo_p03.flv
URI: http://media.example.com/foo_p04.flv
Assured Flow rate:1
AFR Threshold:600
Asset Description file required information:
These fields are optional:
The Version tag is automatically set to the appropriate Release number.
About AFR Threshold
AFR is a feature in Media Flow Controller that stands for Assured Flow Rate; see “AssuredFlow™” on page 48 for overview). AFR guarantees that Media Flow Controller delivers at the specified bitrate and never goes below (or too much above) that rate.
The AFR Threshold value can be specified in the Asset Description File (.dat), if using the On-Demand Publishing scheme (or using a Python script if using encoding.com). It's unit is kbps. Do not specify this value in the Smoothflow Control File; it automatically picks up the value from the Asset Description File (.dat) when SmoothFlow processing is initiated.
The rationale behind providing the AFR value is empirical. For example, if there are 5 profiles each at (200, 400, 600, 800 and 1000kbps). Juniper Networks recommends you set the value for AFR Threshold to be greater than 1/2 the bit rate of the highest profile. In this case you can set it to any value > 500 kbps. This accelerates the switching speed from lower to higher profiles. In this example, the player will switch from 200 to 400 to 600 very quickly and will then slow down in terms of switching to 800 and 1000kbps. Typically, content providers don't like players to very quickly switch to the highest bit rate because this increases their bandwidth costs. If a provider desires that the switching to the highest bitrate happens faster, then set the AFR Threshold value to be equal to the highest available rate (e.g. 1000kbps)

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Media Flow Controller Administrator's Guide and CLI Command Reference
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