[gst-devel] Multiple UDP audio streaming and mixing problem

[Nick Humphries]

Hi,

I'm trying to write a client that will listen to multiple MP3 streams
that's streamed across multiple UDP addresses, and will then separate
out the two stereo channels, amplify each one to an individual
setting, before mixing each mono channel into a single mono stream to
play out.

This works:

gst-launch --print udpsrc multicast-group=227.0.0.10 port=3333 ! mad !
audioconvert ! deinterleave name=d0 d0.src0 ! audioconvert !
audioamplify amplification=3.36 \

! adder name=mix1 ! audioconvert ! alsasink sync=false \

udpsrc multicast-group=227.0.0.10 port=3333 ! mad ! audioconvert !
deinterleave name=d1 d1.src1 ! audioconvert ! audioamplify
amplification=1 ! mix1.

So you see what I'm doing - the left-hand stereo channel gets
amplified 3.36x, the right is amplified 1x, and then they're mixed
together and played back as a mono stream.

One of the requirements is that it has to be able to mix many MP3
streams in this way, with each MP3 stream played back on a different
UDP address, and sometimes there's no UDP data being produced on those
addresses.

So, in this example, 227.0.0.10:3333 is producing data, but
227.0.0.11:3333 is not:

gst-launch udpsrc multicast-group=227.0.0.10 port=3333 ! mad !
audioconvert ! deinterleave name=d0 d0.src0 ! audioconvert !
audioamplify amplification=3.36 \

! adder name=mix1 ! adder name=mix2 ! audioconvert ! alsasink sync=false \

udpsrc multicast-group=227.0.0.10 port=3333 ! mad ! audioconvert !
deinterleave name=d1 d1.src1 ! audioconvert ! audioamplify
amplification=1 ! mix1. \

udpsrc multicast-group=227.0.0.11 port=3333 ! mad ! audioconvert !
deinterleave name=d2 d2.src0 ! audioconvert ! audioamplify
amplification=1 ! mix2.



I get no sound played back when I run this

Running gst-launch with the -v option gives this output:

Setting pipeline to PAUSED ...
Pipeline is live and does not need PREROLL ...
Setting pipeline to PLAYING ...
New clock: GstSystemClock
/pipeline0/mad0.src: caps = audio/x-raw-int, endianness=(int)1234,
signed=(boolean)true, width=(int)32, depth=(int)32, rate=(int)16000,
channels=(int)2
/pipeline0/mad0.src: caps = audio/x-raw-int, endianness=(int)1234,
signed=(boolean)true, width=(int)32, depth=(int)32, rate=(int)16000,
channels=(int)2
/pipeline0/audioconvert0.src: caps = audio/x-raw-float,
rate=(int)16000, channels=(int)2, endianness=(int)1234, width=(int)32
/pipeline0/audioconvert0.src: caps = audio/x-raw-float,
rate=(int)16000, channels=(int)2, endianness=(int)1234, width=(int)32
/pipeline0/audioconvert0.sink: caps = audio/x-raw-int,
endianness=(int)1234, signed=(boolean)true, width=(int)32,
depth=(int)32, rate=(int)16000, channels=(int)2
/pipeline0/d1.sink: caps = audio/x-raw-float, rate=(int)16000,
channels=(int)2, endianness=(int)1234, width=(int)32
/pipeline0/d0.sink: caps = audio/x-raw-float, rate=(int)16000,
channels=(int)2, endianness=(int)1234, width=(int)32
/pipeline0/audioconvert4.src: caps = audio/x-raw-float,
rate=(int)16000, channels=(int)1, endianness=(int)1234, width=(int)32
/pipeline0/audioconvert4.sink: caps = audio/x-raw-float,
rate=(int)16000, channels=(int)1, endianness=(int)1234, width=(int)32
/pipeline0/audioconvert1.src: caps = audio/x-raw-float,
rate=(int)16000, channels=(int)1, endianness=(int)1234, width=(int)32
/pipeline0/audioconvert1.sink: caps = audio/x-raw-float,
rate=(int)16000, channels=(int)1, endianness=(int)1234, width=(int)32
/pipeline0/audioamplify1.src: caps = audio/x-raw-float,
rate=(int)16000, channels=(int)1, endianness=(int)1234, width=(int)32
/pipeline0/audioamplify1.sink: caps = audio/x-raw-float,
rate=(int)16000, channels=(int)1, endianness=(int)1234, width=(int)32
/pipeline0/audioamplify0.src: caps = audio/x-raw-float,
rate=(int)16000, channels=(int)1, endianness=(int)1234, width=(int)32
/pipeline0/audioamplify0.sink: caps = audio/x-raw-float,
rate=(int)16000, channels=(int)1, endianness=(int)1234, width=(int)32
/pipeline0/mix1.sink1: caps = audio/x-raw-float, rate=(int)16000,
channels=(int)1, endianness=(int)1234, width=(int)32
/pipeline0/mix2.sink1: caps = audio/x-raw-float, rate=(int)16000,
channels=(int)1, endianness=(int)1234, width=(int)32


... where it then appears to not do anything, so I CTRL-C it, and this
appears next:


Caught interrupt -- handling interrupt.
Interrupt: Stopping pipeline ...
Execution ended after 2597964000 ns.
Setting pipeline to PAUSED ...
Setting pipeline to READY ...
/pipeline0/mix2.sink1: caps = NULL
/pipeline0/mix2.sink0: caps = NULL
/pipeline0/mix2.src: caps = NULL
/pipeline0/mix1.sink1: caps = NULL
/pipeline0/mix1.sink0: caps = NULL
/pipeline0/mix1.src: caps = NULL
/pipeline0/audioamplify1.src: caps = NULL
/pipeline0/audioamplify1.sink: caps = NULL
/pipeline0/audioamplify0.src: caps = NULL
/pipeline0/audioamplify0.sink: caps = NULL
/pipeline0/audioconvert4.src: caps = NULL
/pipeline0/audioconvert4.sink: caps = NULL
/pipeline0/audioconvert1.src: caps = NULL
/pipeline0/audioconvert1.sink: caps = NULL
/pipeline0/d1.sink: caps = NULL
/pipeline0/d0.sink: caps = NULL
/pipeline0/audioconvert3.src: caps = NULL
/pipeline0/audioconvert3.sink: caps = NULL
/pipeline0/audioconvert0.src: caps = NULL
/pipeline0/audioconvert0.sink: caps = NULL
/pipeline0/mad1.src: caps = NULL
/pipeline0/mad0.src: caps = NULL
Setting pipeline to NULL ...
FREEING pipeline ...



Is there anything obvious that I'm not doing?

Any help is gratefully appreciated,

Nick


-- 
Nick Humphries
nick at egyptus.co.uk
http://www.egyptus.co.uk