[FFmpeg-user] Muxing audio-only MXF

[Erik Dobberkau]

Am Freitag, 1. Dezember 2017 schrieb Robert Krüger :

> Hi Kieran,
>
> On Thu, Nov 30, 2017 at 5:39 PM, Kieran O Leary <kieran.o.leary at gmail.com
> <javascript:;>>
> wrote:
>
> > On Thu, Nov 30, 2017 at 4:38 PM, Kieran O Leary
> > <kieran.o.leary at gmail.com <javascript:;>> wrote:
> > > Hi,
> > >
> > > On Thu, Nov 30, 2017 at 3:46 PM, Robert Krüger
> > > <krueger at lesspain.software> wrote:
> > >> Hi,
> > >>
> > >> is there a way to mux an mxf file only containing a pcm audio stream?
> > When
> > >
> > > You could try using the op-atom muxer as it looks like your command is
> > > defaulting to op1a. Add -f  mxf_opatom to your command line.
> > > ffmpeg -i
> > > /Users/krueger/lesspain/samples/software/compressor/
> > compressor4_1080_25p_apple_devices_best_compat_2s.m4v
> > > -vn -c:a pcm_s16le -f mxf_opatom ~/tmp/ffmpeg_pcm16_rewrap.mxf
> > >
> > > [...]
> > >
> > >>
> > >> Is this a conscious limitation of the muxer or am I missing a command
> > line
> > >> option?
> > >>
> > >
> > > It looks like it. The reasons why I suggested trying OP-Atom is that
> > > this seems to be performing a specific check for OP1a.
>
>
Which is wrong, btw. There is a spec for MXF_OP1a_AES3 to wrap the
respective audio without a picture essence. I would guess MCA labels will
have to be provided though, and also the audio samples would have to be
formatted to AES, which ffmpeg afaik currently doesn't do.

Best,
Erik