Transcoding AVCHD from a Canon HG21 to MXF for Avid Xpress Pro

Question

I have been able to convert the file to a .mov file in DNxHD using FFmpeg, but then Avid Xpress has to transcode it once again into DVCHDPRO. I could elimnate that step if I could go directly to DNxHD in a MXF wrapper. My attempts to do that with FFmpeg so far have not been successful. Can FFmpeg do this and what are the parameters I should use?

Answer 1

I actually figured this out on my own. I used the broadcast version of ffpmeg called ffmbc using the following parameters:

ffmbc -i (inputfile.MTS) -vcodec dnxhd -b 220M -flags +ildct -ab 128K -threads 8 (outputfilename.mov)

• +ildct - this parameter has to do with interlaced modes
• -ab 128K - the audio bitrate (the default, 64k sounds too much like a cell phone call)
• threads 8 - takes advantage of multicore processors; I was able to get a max of about 80% utilization on both cores. You can use more threads with more cores and it definately speeds up the program.

This does NOT create an MXF file, but Avid Xpress Pro recognizes the DNxHD format and does a fast import and the result is beautiful and easy to edit which is what I wanted to begin with.