[MPlayer-users] status of dca/dts decoder

[Andy Furniss]

Carl Eugen Hoyos wrote:
> Andy Furniss <andyqos <at> ukfsn.org> writes:
>
>> Is 7.1 MA lossless supported - I can't get it to work/ be seen.
>
> (Wrong mailing list?)
> No, and I don't know if anybody is actively working on it.
> I suspect there are enough samples.

OK, thanks for the info.

>
> Otoh, what do you mean with supported?
> It is supposed to work fine with MPlayer over HDMI to a
> DTS-HD Master receiver, and of course it has to be "seen" first.
> Could you elaborate?

What I meant was if I do ffmpeg -i or mpplayer -demuxer lavf it only 
shows 5.1 - it does play as 5.1 OK (downmix not OK).

Of course I have don't actually know if I have valid files FWIW I was 
looking at the 7.1 lossless ones from the dts section here -

http://www.demo-world.eu/trailers/high-definition-trailers.php

>
>> Is the downmix from 5.1 to stereo known to have issues?
>
> I am not sure if I understand the question.
> You can test the following:
> $ ffmpeg -request_channels 2 -i input out.wav

This produces a 6 channel wav with four silent - the L&R do show the 
issue in that they are not a stereo downmix and clip - they just seem to 
be everything sent to to 1 channel then duplicated to make 2 (that may 
not be an accurate analysis though).

> $ ffmpeg -i input -ac 2 out2.wav

This produces a 6 channel copy with no downmix.

>
> The first does decoder-downmix, the second downmixes
> through the libswresample library.
> MPlayer by default requests decoder-downmix iirc.

Looks like the decoder downmix isn't working properly then - I can get a 
proper downmix using -channels 6 and pan, and see the stream is OK as 
5.1 with sox.

This applies to a normal 448kbit dts not just the samples from above.

Andy.