This allows setting the muxing/encoding element properties.
**Set properties generically**
[element-properties, boolean-prop=true, string-prop="hi"]
**Mapping properties with well known element factories**
element-properties-map, map = { [openh264enc, gop-size=32, ], [x264enc, key-int-max=32, tune=zerolatency], }
A #GstStructure defining the properties to be set to the element the profile represents.
This allows setting the muxing/encoding element properties.
**Set properties generically**
**Mapping properties with well known element factories**