[FFmpeg-user] Enable all audio channels in Quicktime
rens at onlinemedia.nl
Sun Jan 12 23:19:23 CET 2014
this is being discussed before but i could not really find a solution
or a final conclusion.
For more PRO oriented use the standard always have been having
all channels enabled. All quicktime capture cards and applications
like Softron MovieRecorder or ToolsOnair JustIn behave in this way.
CMD I in Quicktime 7 or Quicktime X will simply show all
available tracks in the Quicktime container. The current
situation with ffmpeg ( 2.1.1) wil only reveal the first audio channel.
ffmpeg -i PRORES_8CH.MOV -map 0 -map -vf scale=1920:1080 \
-pix_fmt yuv420p -c:v libx264 -profile:v high -level 4.0 \
-c:a: copy H264_8CH.MOV
For Quicktime X users there is no way to discover what
I can see the use case if you are working with a finished
movie and properly tagged audio.
But when working on a movie between various
stages in the production, the track layout could well be
1 & 2 Live Recorded Audio
3 & 4 Music
5 & 6 Effect sounds
7 & 8 Narration
So if you want to create a evaluation copy in H264
from a 4K prores master with all the audio tracks enabled
so any casual Quicktime user can hear all the audio still
in separated tracks this is diffcult to achieve.
I would be nice t o have an option -enable_all_tracks or
something similair to adress this issue
As a first attempt I tried to restore the previous behaviour by
patching movenc.c but sofar my understanding of the code
Rens Dijkshoorn < rens at online media.nl >
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