[pulseaudio-discuss] 'clicks' in audio and rtp troubles

[joysn at gmx.net]

Hi!

On Mon, May 28, 2007 at 07:23:26PM +0200, Lennart Poettering wrote:
> On Mon, 28.05.07 18:56, joysn at gmx.net (joysn at gmx.net) wrote:
> 
> > joysn at joysn:~$ pulseaudio -vv --resample-method=src-sinc-best-quality --high-priority=1
> > core-util.c: Successfully gained nice level -15.
> > core-util.c: Successfully enabled SCHED_FIFO scheduling.
> > caps.c: dropping root rights.
> 
> Hmm, this probably means you're running a really awful non-"preempt"
> kernel whith a large HZ. Last time I looked Ubuntu shipped a shitty
> kernel like that. Dunno if they still do. You might want to change
> that.

i use a vanilla kernel with Ingo Molnars RT patch:
Linux joysn 2.6.21-rt8 #1 PREEMPT RT

> At the cost of higher latency you may fix this by using larger hw
> buffers. To do that you have to comment the "load-module
> module-hal-detect" line in your configuration and load
> "module-alsa-sink" manually. When doing that pass fragment_size=4096
> or similar.
> 
> See http://pulseaudio.org/wiki/Modules#modulealsasink for more info.

i wanna try this. if i have a need for really low latency time i can 
use JACK ;)

> Also, a VLC client with minor modifications should be able to pick up
> the SAP announcements. (i.e. just replacing the multicasting address
> to listen on -- ideally that address should be configurable. maybe it
> is time to file a feature request bug for vlc for this)

hm. vlc 0.8.6 has a configurable mcast address for SAP. the playlists
also 'see' the stream but when i try to connect to ist vlc reports:

live555 error: Nothing to play for rtsp://v=0
o=chris 3389376985 0 IN IP4 192.168.0.3
s=PulseAudio RTP Stream on joysn
c=IN IP4 225.0.0.1
t=3389376985 0
a=recvonly
m=audio 554 RTP/AVP 10
a=rtpmap:10 L16/44100/2
a=type:broadcast

main error: no suitable access module for `sdp://v=0
o=chris 3389376985 0 IN IP4 192.168.0.3
s=PulseAudio RTP Stream on joysn
c=IN IP4 225.0.0.1
t=3389376985 0
a=recvonly
m=audio 554 RTP/AVP 10
a=rtpmap:10 L16/44100/2
a=type:broadcast

> The only app I tested my code against have been mplayer and
> ... wireshark. ;-)

ok. i'll try to modify wireshark to use a audio decoder lib and route
the results to an available audio device ;-)
i played with mplayer, but annot figure out the syntax for the rtp 
stream? rtp://225.0.0.1?

Joysn