[Ffmpeg-devel] Raw aac

[Måns Rullgård]

Erik Slagter said:
> On Wed, 2006-02-08 at 01:13 +0000, M?ns Rullg?rd wrote:
>> Erik Slagter <erik at slagter.name> writes:
>>
>> > On Tue, 2006-02-07 at 11:57 +0000, M?ns Rullg?rd wrote:
>> >> > I've tried many combinations, but it doesn't seem ffmpeg supports
>> >> > writing raw AAC. Is there actually something like this or should it be
>> >> > encapsulated in ADTS or something alike?! It doesn't seem ffmpeg does
>> >> > support this either. Is this true, is there a workaround?
>> >>
>> >> Really raw AAC is mostly useless.  If you don't want a full
>> >> container format, ADTS is probably the most convenient.  I don't
>> >> think ffmpeg supports it, but it should be fairly simple to add.
>> >
>> > IIRC gpac does understand ADTS, but as ffmpeg doesn't, that is not an
>> > option for me for the moment.
>>
>> Now it does.
>
> Quick test: encoding works

Yes, I tested that much before committing ;-)

> Extracting AAC from mp4 to ADTS from a file encoded by ffmpeg-cvs from
> about four months ago, gives invalid data, "file" says "data" and gpac
> reports the sampling rate and other metadata wrong. Gpac extracts the
> track from the mp4 itself fine, though.

It figures.  The mp4 file contains raw aac, so the adts headers would have
to be created.  I guess the aac outputformat could do this.

> I'll have to check if this also happens with files encoded/muxed by a
> recent ffmpeg cvs version.

Don't waste your time on that.  It won't work.  Patches welcome, as always.

-- 
M?ns Rullg?rd
mru at inprovide.com