[Ffmpeg-devel] dts decoding broken?

Måns Rullgård mans
Sat Feb 17 00:00:52 CET 2007


Uoti Urpala <uoti.urpala at pp1.inet.fi> writes:

> On Fri, 2007-02-16 at 21:24 +0000, M?ns Rullg?rd wrote:
>
>> How would an application request downmixing?
>
> I'm not sure what the exact syntax should be, but adding some field for
> that (if nothing more complicated) shouldn't be too hard. I also just
> checked the libdts documentation and it talks about "default behavior,
> which is to apply the full dynamic range compression as specified in the
> DTS stream". I'm sure that someone would want an option to turn that off
> in situations such as a home theater, and since it talks about "as
> specified in the DTS stream" it's probably not possible to get the same
> effect by any processing after the decoder.

All these options are of course desirable.  Yet, none of the are
currently possible.

>> > Is the channel order even documented anywhere in FFmpeg (outside
>> > libdts)?
>> 
>> The order is whatever ALSA expects.
>
> OK maybe it works with ALSA using a 6-channel setup (have you verified
> all the channels really are right?),

All my DTS files play correctly on my system.

> but at least ALSA doesn't seem to downmix 6-channel playback
> properly for headphones by default on my machine.

Usually, the "default" device does something reasonable.  Is it not
working for you?

-- 
M?ns Rullg?rd
mans at mansr.com




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