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Rahul Agarwal
2003-11-26, 14:43
I use slimserver to access music collection at home and listen to it
while I am at school. I have set it up to downsample the mp3s to 96 kbps
so that it can stream continuously. While at school yesterday, a friend
of mine also wanted to listen to my collection. When both us played
songs at the same time, the server was overloaded trying to downsample 2
separate songs at the same time and the performance degraded (sorry,
it's an old PIII 733 Mhz system).

Then I thought of trying the synchronized playback option, so that both
of us could listen to music and at the same time save the server from
processing 2 separate songs. I am not sure but I think that might also
save bandwidth since it is sending only 1 stream.

Anyways, I looked for the synchronization option and it looks like it is
available for the hardware players only. Is this true? If yes, is there
any specific reason to not extend that to the remote streams?

If there aren't any obvious reason for not doing it, I would like to see
it implemented. I could also try to help even though my perl skills
might not be up to the mark.

Thanks,
--
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ragarwal (AT) fit (DOT) edu

Get my public key at http://my.fit.edu/~ragarwal/tipiyano.asc

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Kevin Deane-Freeman
2003-11-26, 15:02
Quoting Rahul Agarwal <ragarwal (AT) fit (DOT) edu>:


>
> Then I thought of trying the synchronized playback option, so that both
> of us could listen to music and at the same time save the server from
> processing 2 separate songs. I am not sure but I think that might also
> save bandwidth since it is sending only 1 stream.


Unless you are both sitting at the same PC, the bandwidth wont be reduced. Even
given one downsampled stream, it would be seind it out copied to two locations.
I wouldn't expect much reduction.
>
> Anyways, I looked for the synchronization option and it looks like it is
> available for the hardware players only. Is this true? If yes, is there
> any specific reason to not extend that to the remote streams?

The hardware players have a defined buffer and latency, plus a protocol for
breaking up the stream into chunks. This allows the tight matching and
packetising of the streams for synchronisation of the players. Software players,
especially when downsampling brings in far too much latency as well as a LAME
process which handles the re-encoding.
>
> If there aren't any obvious reason for not doing it, I would like to see
> it implemented. I could also try to help even though my perl skills
> might not be up to the mark.
obvious, you mean aside from being designed primarily to support the Hardware
that Slimdevices bases their business on? When it was attempted, it didn't work
very well, many complained, some were happy just to have same music even if it
was way off. I suspect to have it now downsample BEFORE sync is also going to
require a major reqork of the architecture. Each client, hardware or software
is considered a distinct object which launches its own processes when needed for
transcoding, decoding, or downsampling.

If you realy want internet streaming, best to look into something like Andromeda
or AudioStreamer, hand have THAT connect as a single client to your slimp3
server. Then you can connect from anywhere on the internet to a server that is
properly designed to be an internet radio server.

-kdf