[FFmpeg-user] Help with Concatenating Please

[Mark Scott]

Hello,
I'm very new to ffmpeg and I don't have much experience using command lines
to encode video.

I need to take an Apple ProRes 4444 file, 1920x1080, 23.98 fps, 16 bit
integer stereo audio,
and encode it to be Apple ProRes 422 HQ 1920X1080, 23.98fps 24bit integer
stereo audio.
The trick is, I need to add 2 seconds of black silent video to the head of
the encoded file. Would this be accomplished by concatenating the original
video file, with a separate video file that has the 2 seconds of black?

I have been using ffmpeg for very basic encoding. I believe this would be a
very complicated command line. I would appreciate any advice.