[Ffmpeg-devel] dts decoding broken?

[Måns Rullgård]

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

> On Fri, 2007-02-09 at 19:19 +0200, Uoti Urpala wrote:
>> On Fri, 2007-02-09 at 17:52 +0100, mail at kraymer.de wrote:
>> > same with 5.1 dts. Now, I only get 2 out of 6 channels without downmix,
>> > even with -channels 2 and/or -af channels=2. What I get is mainly music
>> > and background sounds, voices are missing.
>> > I did some regression testing and it turned out that a change in ffmpeg,
>> > namely commit -r 7839, introduced that behavior. Using recent mplayer svn
>> 
>> That commit changes the decoder to output the full number of channels by
>> default. Unfortunately it also seems to completely remove the ability to
>> use the libdts downmixing functionality.
>> 
>> The rest of the channels are there and you can access them by explicitly
>> specifying some conversion to 2 channels with "-af pan" for example.
>> However having a way to use the libdts downmixing would be better.
>
> Does anyone intend to restore support for the downmixing functionality?

There is nothing to restore.  It used to *always* do downmixing with
no option to get all the channels.  How would an application request
downmixing?

> Can anything sanely use the current 6-channel output?

Works fine here.  Pretty much any motherboard less than a few years
old seems to have 6-channel or better sound onboard, and there are
many suitable PCI sound cards available.

> Is the channel order even documented anywhere in FFmpeg (outside
> libdts)?

The order is whatever ALSA expects.

I changed the libdts wrapper to decode all channels because Reimar was
whining.  Now you and Sebastian are whining instead.  It seems
impossible to satisfy all of you.

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