The Transcoder in Wowza Streaming Engine™ media server software supports bi-directional frames (B-frames) when using the default MainConcept encoder implementation and the Main or High Profile. However, B-frame generation is turned off by default.
You can change the number of B-frames generated or disable B-frames for a given <Encode> block using the mainconcept.reordering_delay parameter. This parameter only works with AVC/H.264 encoding. In your Transcoder template, add the parameter to the Video/Parameters container in the <Encode> block.
<Parameter>
<Name>mainconcept.reordering_delay</Name>
<Value>3</Value>
<Type>Integer</Type>
</Parameter>
The Value property specifies the maximum distance between predicted frames (P-frames) and controls the insertion of B-frames between each P-frame.
The default value is 1, meaning no B-frames will be generated. A value of 3 instructs the Transcoder to generate and insert up to two B-frames between each P-frame.
