Re: Launching Rygel on headless server

[Cefn Hoile <mail gnome org cefn com>]

On 29 May 2012 12:48, Cefn Hoile <mail gnome org cefn com> wrote:
> On 29 May 2012 10:44, Jens Georg <mail jensge org> wrote:
>> On Mo, 2012-05-28 at 22:56 +0100, Cefn Hoile wrote:
>>> Once I've installed all the debugging packages you mentioned, the
>>> Segfault stops arising.
>>
>> That means you managed to install the gst-plugins-base libraries without
>> installing the base plugins. Looks like some packaging dependendy
>> problems.
>>
>>>
>>> I was now able to see more meaningful errors when trying to attach to
>>> the wav stream, which were associated with missing packages - needed
>>> gstreamer0.10-pulseaudio to give me pulsesrc and
>>> gstreamer0.10-plugins-good to give me wavpackenc
>>
>> Btw. wavpack is not WAV. wavpack is a lossless but compressing audio
>> codec, similar to FLAC. WAV "encoding" is done by wavenc.
>>
>>>
>>> I've arrived at this error which I don't know how to handle when
>>> attaching to the Gstreamer Wave stream using VLC's UPNP browser (which
>>> detects a stream from Rygel at my local
>>> http://192.168.1.128:57845/GstLaunch/i/bXlwdWxzZWF1ZGlvc2luaw%3D%3D.wav
>>> )
>>>
>>> (rygel:3140): Rygel-WARNING **: rygel-http-request.vala:97: Invalid seek request
>>
>> This is a known bug we need to address at some point; unfortunately this
>> is a bit tricky (https://bugzilla.gnome.org/show_bug.cgi?id=659432 or
>> https://bugzilla.gnome.org/show_bug.cgi?id=674736) It's ok with VLC as
>> it does the right thing (retry without seeking).
>>
>>> (rygel:3140): Rygel-CRITICAL **: Error from pipeline
>>> RygelHTTPGstResponse: pulsesrc.c(1480): gst_pulsesrc_prepare ():
>>> /GstPipeline:RygelHTTPGstResponse/GstBin:bin0/GstPulseSrc:pulsesrc0
>>
>> Are you sure that the headphone thing is the correct pulse source?
>>
>> I've got something like
>>
>> mypulseaudiosink-title=Audio on @HOSTNAME@
>> mypulseaudiosink-mime=audio/L16;rate=44100;channels=2
>> mypulseaudiosink-launch=pulsesrc device=alsa_output.pci-0000_00_1b.0.analog-stereo.monitor
>>
>> in my rygel.conf
>>
>>
>
> I'm still surprised it's a segfault, rather than a more elegantly
> handled error, but glad I'm not experiencing it anymore.
>
> I've duplicated your suggested lines, in the hope that this would
> relay the wave data from the soundcard without reencoding. I replaced
> the alsa device name with the first device name which shows up when I
> run
>
> pacmd list-sources
>
> ...as the mpd user, the name of this device being...
>
> alsa_output.usb-0d8c_C-Media_USB_Headphone_Set-00-Set.analog-stereo.monitor
>
> Inspecting the soundcard through Alsa tools suggests that the hardware
> shows up as...
> mpd@gardner:/root$ cat /proc/asound/card0/pcm0p/sub0/hw_params
> access: MMAP_INTERLEAVED
> format: S16_LE
> subformat: STD
> channels: 2
> rate: 44100 (44100/1)
> period_size: 44100
> buffer_size: 88200
> ...so I'm guessing the mime type information matches with the
> declaration you provided too.
>
> Having launched rygel (logged in as the mpd user) and when trying to
> stream using VLC on my desktop from the detected endpoint (which
> appears correctly), rygel reports the sync error as normal when the
> stream starts but doesn't report a critical Gstreamer error, so I
> guess it's doing something. In all the incorrect configurations so
> far, the stream died immediately, so this is something like progress.
>
> However, I get VLC reporting 00:00 seconds in the stream and no sound
> audible. Are you able to stream audible sound to VLC using the
> configuration you shared with me?
>
> Thanks for all your help. I would have given up long ago without
> confident guidance on this. I've attached my current rygel
> configuration and the pacmd report on my devices in case anything
> leaps out which needs to be differently configured.
>
> Cefn
> http://cefn.com

On further investigation I had some concerns that pulseaudio might not
be in use by MPD, (and I'm still not sure it is) but running...
cat /dev/urandom | pacat -d
"alsa_output.usb-0d8c_C-Media_USB_Headphone_Set-00-Set.analog-stereo"
...generates noise from the speakers, without any noise appearing via
the rygel-served stream, which remains at 00:00.

I think this proves that Pulseaudio is indeed in use, and I'd expect
noise via rygel in VLC, but instead it's silent. Hopefully this is a
better test case to pursue.

Cefn
http://cefn.com