HyperDeck multi-mono audio to surround

I recently made a recording with a Blackmagic Design HyperDeck 12G from an HDMI source which had 5.1 audio. Unfortunately, the HyperDeck recorded 16 independent mono channels, which meant that everything was on the center channel when I imported it into Final Cut Pro X. In addition, the C and LFE channels were swapped in the same manner that Media Express swaps them.

To fix the issue, I was able to use a similar command to what I used for fixing recordings from Media Express (see my post on that issue). The one change was using “-map 0:1” as the HyperDeck stores the video as Stream #0. This command has the nice side-effect of stripping the extra unused audio channels from the file, which also reduces the file size.

ffmpeg -i input.mov \
-c:v copy \
-filter_complex \
"pan=6c|c0=c0|c1=c1|c2=c3|c3=c2|c4=c4|c5=c5[out1]" \
-map 0:1 -map [out1] -c:a pcm_s24le \
output.mov

I also have some 7.1 sources, and for them I’ll be using a slightly modified version of the command.

ffmpeg -i input.mov \
-c:v copy \
-filter_complex \
"pan=8c|c0=c0|c1=c1|c2=c3|c3=c2|c4=c4|c5=c5|c6=c6|c7=c7[out1]" \
-map 0:0 -map [out1] -c:a pcm_s24le \
output.mov