[FFmpeg-user] Adding custom keys/val pairs to -progress

[PSPunch]

Hi,

Is there a way to add custom key/val pairs to the info sent when using  
the "-progress" option?

For example, to the current output below,

---- Progress output ----
frame=480
fps=27.9
stream_0_0_q=-1.0
bitrate=  80.5kbits/s
total_size=193518
out_time_ms=19242000
out_time=00:00:19.242000
dup_frames=0
drop_frames=0
progress=continue
-------------------------

.. I would like to add
program=ch01
at the end.
For my purpose, this can be hard written in arguments at startup.


The ultimate goal is to have each of many FFmpeg instances send this  
over UDP to a centralized activity monitor. It would widen options for  
the recipient's design if an identifier of origin can be added to the  
progress info.


Thank you.

-- 
David Shimamoto