[MPlayer-users] Pulsing static sound with -ac hwac3 in Mac OS X

[Ergzay]

On 2007/03/05, at 13:36, Marcus Svensson wrote:

>  Guillaume POIRIER wrote:
>> Hi,
>>
>> On 3/4/07, Marcus Svensson <macke at illion.se> wrote:
>>> Guillaume POIRIER wrote:
>>> > Hi,
>>> >
>>> > On 3/4/07, Marcus Svensson <macke at illion.se> wrote:
>>> >> I have a problem getting AC3 passthrough to work. With the  
>>> command line
>>> >> option -ac hwac3 set all I get is a nasty pulsing static sound.
>>> >>
>>> >> The log tells me:
>>> >>
>>> >> Forced audio codec: hwac3
>>> >> Opening audio decoder: [hwac3] AC3/DTS pass-through S/PDIF
>>> >> No accelerated IMDCT transform found
>>> >> hwac3: switched to AC3, 384000 bps, 48000 Hz
>>> >> AUDIO: 48000 Hz, 2 ch, ac3, 384.0 kbit/25.00% (ratio:  
>>> 48000->192000)
>>> >> Selected audio codec: [hwac3] afm: hwac3 (AC3 through S/PDIF)
>>> >>  
>>> ===================================================================== 
>>> =====
>>> >>
>>> >> AO: [macosx] 48000Hz 2ch ac3 (1 bytes per sample)
>>> >>
>>> >> Any suggestions?
>>> >
>>> > I don't think hwac3 is supposed to work on OSX, sorry :(
>>
>>> Is there any way to get spdif passthrough to work in OS X then?
>>>
>>> It works fine in VLC.
>
> MPlayer is using CoreAudio right? CoreAudio has no support for  
> passthrough. I wonder how it is passedthrough in VLC and OS X DVD  
> Player. Does anyone know what library VLC is using for audio  
> (passthrough)?

You sure about that? Mac towers and macbook pros have digital audio  
out. I would bet that it is passthrough (unless I do not understand  
what passthrough is). If you have DTS audio I'm betting it would pass  
that raw bitstream out to a hardware DTS decoder.

Ergzay