Thread: WIP: USB audio output - N900 as an "audiophile" portable music player
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Oblomow is offline Oblomow
2012-03-29 , 22:15
Posts: 72 | Thanked: 184 times | Joined on Apr 2011 @ Germany
#42
So, I did a few experiments with gstreamer, but without much success. But maybe someone finds this useful, though.

First, one needs to install the gstreamer0.10-alsa package:

Code:
sudo apt-get install gstreamer0.10-alsa
this adds an gstreamer plugin for alsa outout/input. One can now play e.g. a mp3 file back using the appropriate gstreamer-pipeline:

Code:
gst-launch filesrc location=thesong.mp3 ! decodebin ! audioconvert !
audioresample ! alsasink device=hw:1,0
Probably gstreamer does this with dsp-assisted decoding, but I guess the main cause for battery drain is the host mode part itself, so it does not seem to help much.

I did not manage to play anything through usb with Maemo apps, nor found a way to set an system wide standard sink. Some website proposed to use
Code:
gconftool-2 --type string --set /system/gstreamer/0.10/default/audiosink "alsasink device=hw:1,0"
gconftool-2 --type string --set /system/gstreamer/0.10/default/musicaudiosink "alsasink device=hw:1,0"
but it seems like Maemo apps do not rely on this.

So, not so useful for playback, but could be nice for recording directly in ogg or flac using a gstreamer pipeline.

It seems however like rockbox is using gstreamer, and has "pulsesink" as output sink hardcoded (http://git.rockbox.org/?p=rockbox.gi...cm-gstreamer.c), so one could try to change this and recompile (or ask the author to make it configurable somehow).

Does anyone know if there's a way to force apps using gstreamer to a special sink? Or make autoaudiosink redirecting to it?
 

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