[FFmpeg-user] preset files

[Moritz Barsnick]

On Tue, Sep 04, 2018 at 16:25:47 -0400, Scott Johnson wrote:

> I'm using a third party compiled API, to talk to FFmpeg. I can't
> change the command line structure. I would have to purchase the API
> source to do it.

Francois suggested a wrapper, i.e. a script which is called ffmpeg,
which adds there options under the hood. Your "API" would call this
script, assuming it is the ffmpeg binary.

> From: ffmpeg-user <ffmpeg-user-bounces at ffmpeg.org> On Behalf Of Francois Visagie
> As far as I know the use of preset files has been deprecated.

At first glance, I don't see any deprecation code around its
implementation.

On Fri, Aug 31, 2018 at 10:06:35 -0400, Scott Johnson wrote:
> My video is using the h.264 codex. Do I just need to make a file named
> h264.ffpreset, with the following lines:
>
>                c:a=aac
>
>                max_muxing_queue_size=99999

You could have just tried (as I am doing now). Using "-loglevel debug",
ffmpeg will tell you about the parsing of this file. E.g.

> keks.ffpreset: Invalid option or argument: 'c:a=aac
> ', parsed as 'c:a' = 'aac'

This works if changed to
acodec=aac
(the c:X format is apparently not supported).

When that is changed, I get:
> Applying option fpre (set options from indicated preset file) with argument keks.ffpreset.
> ffpreset[keks.ffpreset]: set 'acodec' = 'aac'
> ffpreset[keks.ffpreset]: set 'max_muxing_queue_size' = '99999'
> keks.ffpreset: Invalid option or argument: 'max_muxing_queue_size=99999
> ', parsed as 'max_muxing_queue_size' = '99999'

Why the latter isn't understood I do not know, though. Someone else
will need to pitch in, as I don't have the time to investigate right
now.

Cheers,
Moritz