H264/AAC Streaming Sound Problem

Wowza Streaming Engine
1

I have set up wowza to monitor for sdp files so here is what I’m trying:

Streaming audio in AAC and video in H264 to wowza through RTP using GStreamer

Ports:

Audio - RTP:5000 RTCP:5001

Video - RTP:5002 RTCP:5003

Here is the sdp that I’m sending to the folder monitored by wowza: http://pastebin.com/raw.php?i=y5838xay

Here is the GStreamer verbose output: http://pastebin.com/raw.php?i=Kr3F8JU7

Just to ensure that the payload sizes and clock rates are right

And here is wowza output: http://pastebin.com/raw.php?i=qQi0QKzp

The video streaming works fine but there is no sound, I’m using flowplayer to watch the stream.

Also I have set up the stream type to rtp-record so then I can download the result and in the .flv file there is no sound there also.

Just to ensure that I was sending the information right I made a GStreamer client for that configuration and it worked fine (audio and video).

Here is the pipeline on a local test: http://pastebin.com/raw.php?i=MSmxjnxJ

I double checked all configurations I could think of and everything seems fine from my understanding.

If someone can figure this out it would be appreciated.

Thanks!

2

The SDP file is misssing information for the audio channel:

v=0
o=- 1188340656180883 1 IN IP4 187.78.107.222
s=Session streamed by GStreamer
t=0 0
c=IN IP4 187.78.107.222
m=video 5000/2 RTP/AVP 96
a=rtpmap:96 H264/90000
m=audio 5002/2 RTP/AVP 96
a=rtpmap:96 MP4A-LATM/44100

I would expect to see a line that looks like this:

a=fmtp:96 profile-level-id=15; object=2; cpresent=0; config=400024203fc0

I might also see if there is a way to configure GStreamer to use something other than LATM for the packetizer for audio. I have seen issues with the way this is done by GStreamer. It would be better to use mpeg4-generic (rfc 3640).

Looks like there is more info here:

http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-good-plugins/html/gst-plugins-good-plugins-plugin-rtp.html

rtpmp4gpay

Charlie

3

Hi

Wowza will have to process the input stream regardless of what what type it is, so choose which ever you find easy to manage.

Jason

4

Thanks a lot charlie, it worked beautifully

I have a question. As you see I’m streaming AAC and h264 separately over RTP and watching it in flowplayer. My question: is this way ok to achive a low processor load on the server or would be better to send it muxed in a way that wowza just forward to the flash player?

A way I have found so far (but not successfuly implemented yet): Mux it into a MPEG-TS then send over RTP

I made a test to see the overhead

Ideal (no protocol overhead): 18kb/s

RTP separately: 22,1kb/s

MPEG TS over RTP: 29,3 kb/s

So it will introduce a significantly overhead. The question is, will it worth? I’ll have to work with a low bandwidth on the sender side so I would mux it (in this way or another) if it definetly reduces the server load.

I think I can use another mpeg container (or flv) just need to see how I do that in GStreamer, but thats the way I found easier.

Whats your opinion on “separately/low overhead/higher server load” vs " muxing/higher overhead/lower server load"?

Thanks a lot, I have received great support so far here from wowza forum.

5

up