How to work with R3D and RMD files? FFMPEG?
R3D files are essentially just a custom container that holds video encoded in JPEG2000 and PCM audio. Though ffmpeg only supports the RED container until version 3, not the newer version 4 (see this).

You can convert RED version 3 files the same way you would convert any other video with ffmpeg.
F.e. to h264 use the command below. Doesn't make much sense though to use h264 for further editing, you will have to use an intermediate codec and or container that your software supports:

ffmpeg -i input.r3d -vcodec libx264 -preset slow output.mp4


The usual way though is to use the free REDCINE-X tool provided by RED:
https://www.red.com/downloads?category=Software&amp;release=final

It allows you to transcode your r3d files into pretty much any desirable format as long as its supported by V4W (Video for Windows, e.g. all codecs installed on your system). Or QuickTime on Mac.

Redcine is also the only useful way to do something with the RMD files.