Icecast - Oct 2009 - Vorbis still glitching on metadata update?

Greetings,

I am trying to track down a bug with intermittant glitching in our  
Vorbis streams.

I am running Icecast 2.3.2 on Ubuntu 9.04.

Several Vorbis clients seem to glitch on some (not all) metadata  
updates. As we update metadata 3 to 4 times a minute, this is  
something we are trying to fix, VLC gives the following output on  
metadata update:

main warning: the mixer got a packet in the past (22371)
main warning: the mixer got a packet in the past (1038)
main warning: mixer start isn't output start (398)
ogg debug: end of a group of logical streams
ogg debug: found vorbis header
ogg debug: will reuse old stream to avoid glitch
ogg debug: beginning of a group of logical streams
main error: ES_OUT_RESET_PCR called
main warning: received buffer in the future
main debug: Buffering 0%
main debug: Buffering 0%
main debug: Buffering 19%
main debug: Buffering 40%
main debug: Buffering 63%
main debug: End of audio preroll
main debug: Buffering 84%
main debug: Stream buffering done (1274 ms in 144 ms)
main debug: Decoder buffering done in 0 ms

For testing you can compare:

http://radio.hiof.no/nrk-jazz-128 (MP3 stream, no glitching)
http://radio.hiof.no/nrk-jazz-128.ogg (Vorbis stream, glitches)

Metadata is updated via the web admin interface from a script.

Has anyone else encountered this or know a way to fix this issue?

Regards,

--
Andreas Bergstr?m
?stfold University College
Dept. of Computer Sciences
Tel: +47 69 21 53 71
http://media.hiof.no/

On Tue, Oct 27, 2009 at 10:09:22AM +0100, Andreas Bergstr?m
wrote:
> 
> Several Vorbis clients seem to glitch on some (not all) metadata  
> updates. As we update metadata 3 to 4 times a minute, this is  
> something we are trying to fix, VLC gives the following output on  
> metadata update:
> 
[?]
> http://radio.hiof.no/nrk-jazz-128.ogg (Vorbis stream, glitches)
> 
MPlayer plays very well, moc (music on console) too (but it reports `Stream
error' on each meatadata update).

Reference implementation ogg123 produces glitches. It says ALSA underrun and
rebufferes the stream.

All players tested with 128 kB buffer.

BTW, I your IPv6 streams do not work because:

$ ping6 -n radio.ipv6.hiof.no
PING radio.ipv6.hiof.no(2001:700:a00:ff33:216:3eff:fe75:c27d) 56 data bytes
From 2001:700:0:1003::2 icmp_seq=1 Destination unreachable: Address unreachable

-- Petr
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On 27. okt. 2009, at 11:14, Petr Pisar wrote:
 > MPlayer plays very well, moc (music on console) too (but it reports  
`Stream
> error' on each meatadata update).
OK, thank you.
> Reference implementation ogg123 produces glitches. It says ALSA  
> underrun and
> rebufferes the stream.
So could be clientside, could be serverside, time to dig deeper, I  
guess.
> All players tested with 128 kB buffer.
>
> BTW, I your IPv6 streams do not work because:
>
> $ ping6 -n radio.ipv6.hiof.no
> PING radio.ipv6.hiof.no(2001:700:a00:ff33:216:3eff:fe75:c27d) 56  
> data bytes
> From 2001:700:0:1003::2 icmp_seq=1 Destination unreachable: Address  
> unreachable

Ah thanks, found a configuration error, it _should_ work now.

Regards,

--
Andreas Bergstr?m
?stfold University College
Dept. of Computer Sciences
Tel: +47 69 21 53 71
http://media.hiof.no/

Hi,

Andreas Bergstr?m schrieb:
> Metadata is updated via the web admin interface from a script.
>   
sorry for stating the obvious:
Injecting the metadata directly within the source client is not an 
option for you?


Maybe Karl can say something about the metadata update?

Cheers

Thomas

On 27/10/09 09:09, Andreas Bergstr?m wrote:
> Greetings,
>
> I am trying to track down a bug with intermittant glitching in our
> Vorbis streams.
>
> I am running Icecast 2.3.2 on Ubuntu 9.04.
>
> Several Vorbis clients seem to glitch on some (not all) metadata
> updates. As we update metadata 3 to 4 times a minute, this is
> something we are trying to fix, VLC gives the following output on
> metadata update:
> For testing you can compare:
>
> http://radio.hiof.no/nrk-jazz-128 (MP3 stream, no glitching)
> http://radio.hiof.no/nrk-jazz-128.ogg (Vorbis stream, glitches)
inserts for ogg are different to mp3. It is generally better to get the 
source client to do that as it will be in sync with the content.
> Metadata is updated via the web admin interface from a script.
>
> Has anyone else encountered this or know a way to fix this issue?
>
from here, ogg123 is ok (although a 128k buffer, not sure what the 
prebuffer % is, seems to be low, try increasing those).  mplayer is fine 
but vlc keeps resetting itself in a major way on a new logical stream. 
The format of the stream looks ok, I don't see any specific issue with 
it. There is one other thing I can check but I'll have to get back to 
you on that.

karl.

On Tue, Oct 27, 2009 at 04:40:02PM +0000, Karl Heyes
wrote:
> On 27/10/09 09:09, Andreas Bergstr?m wrote:
> > http://radio.hiof.no/nrk-jazz-128.ogg (Vorbis stream, glitches)
> 
> from here, ogg123 is ok (although a 128k buffer, not sure what the 
> prebuffer % is, seems to be low, try increasing those).
I check it out with bigger buffer (size 512 kB, prebuffer 80 %) again
and it sounds perfectly now. Maybe mplayer has better TCP tunning than
ogg123 because the buffer fill stays around 37--40 % but ogg123 shows
decreasing fill periodically with 128kB buffer.

-- Petr
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On 27. okt. 2009, at 17:40, Karl Heyes wrote:
> inserts for ogg are different to mp3. It is generally better to get  
> the
> source client to do that as it will be in sync with the content.
>
I see, thank you. I guess the challenge will be finding a system which  
allows insertion of metadata on the encoding side.
>> Metadata is updated via the web admin interface from a script.
>>
>> Has anyone else encountered this or know a way to fix this issue?
>>
>
> from here, ogg123 is ok (although a 128k buffer, not sure what the
> prebuffer % is, seems to be low, try increasing those).
I can look into increasing the burst-on-connect value.
>  mplayer is fine
> but vlc keeps resetting itself in a major way on a new logical stream.
> The format of the stream looks ok, I don't see any specific issue with
> it. There is one other thing I can check but I'll have to get back to
> you on that.
OK, I will await that then while looking into inserting metadata at  
encoding time.

Regards,

--
Andreas Bergstr?m
http://blog.andreasb.net