Dynamic-bitrate is the ability to change encoding bitrate (target-bitrate) while the encoder is active.
To change the bitrate of the video at frame number 100 to 1 Mb/s:
zynqmp_vcu_encode -w 3840 -h 2160 -e avc -r 5000 -o /run/op.h264 -i /run/input.yuv -d BR:100:1000
The syntax of the -d parameter is:
<keyword>:<frame number>:<value>