[FFmpeg-user] DNxHD / DNxHR conversions for Avid

[Media Mouth]

We've got a bunch of mp4s that need converting to Avid-native MXF  that they can be dropped into a ../Avid MediaFiles/MXF folder without being ingested.
(In other words, bypassing the need to importing/transcoding and avoiding using AMA+transcoding)

The mp4 sources are 29.97, 23.976 and 25fps  (at 3840x2160)
The Avid project is DNxHD36 1920x1080 @ 24fps, and the mandate is to not mix frame rates on the timeline.

So the current workflow involves using Resolve, where we select the mp4s and Clip Attributes > Video Frame 24
then throw onto a timeline and export using format MXF Op-Atom using Codec DNxHD 1080p 36 8bit video
That generates files that can be drag and dropped to Avid Media folders which then show up in bins via importing the msmMMOB.mdb (per folder media database)

I'm trying to achieve the same Avid-compatible MXFs using FFmpeg
So far I haven't figure out how do DNxHD w/o getting an error in FFmpeg
And my attempts to do DNxHR, while successful in terms of getting a playable file and no errors on the FFmpeg,
do cause an error on the Avid side if you drop them directly in an Avid MediaFiles/MXF folder


Most successful FFMPEG command (the one that resulted in the above error)  so far has been this...

ffmpeg -i /path/to/source.mp4 \
-c:v dnxhd \
-vf 'scale=1920:1080,fps=24/1,format=yuv422p' \
-profile:v dnxhr_lb \
/path/to/dest.mxf