[solved] Strange Problem Streaming via RTP

[Meshuggah]

Hello,

I have some Problems with streaming via RTP. My OS is Debian Lenny (testing), I built vlc today from the git-sources (0.9.0).

I have an H.264-File (sample.mp4), which works fine with vlc and ffplay when loading file from HDD.

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vlc sample.mp4 ffplay sample.mp4

This file should be streamed via rtp, so I run the server with

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vlc sample.mp4 --sout '#rtp{dst=234.5.6.7,port=20000,mux=ts}'

When using vlc as client

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vlc rtp://@234.5.6.7:20000

I have audio but no video.


When using ffplay as client

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ffplay rtp://234.5.6.7:20000

there is video but no audio.


The problem is the same when using jvlc instead of the command line to run the server.


Has someone an idea, what the failure could be or where I can look for a solution?


[edit]
After hours of searching&trying I found the failure within the transcoding process with ffmpeg.

Old version:

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ffmpeg -i sample.mov -f mp4 -vcodec libx264 -acodec libfaac sample.mp4

New version (only added the "-bf" option (sets the number of B-Frames))

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ffmpeg -i sample.mov -f mp4 -vcodec libx264 -bf 5 -acodec libfaac sample.mp4

The problem with the old version were (I think so - correct me if I'm wrong) the missing PPS/SPS-Informations within the stream (only sent once at the beginning?)

Maybe it helps someone with similar problems...
[/edit]

[khushboo]

Hi,
i need help for streaming on rtp from vlc server to ffplay client..
ffplay rtp://234.5.6.7:20000 is not working
Any help appreciated.

[Mauro]

New version (only added the "-bf" option (sets the number of B-Frames))

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ffmpeg -i sample.mov -f mp4 -vcodec libx264 -bf 5 -acodec libfaac sample.mp4

The problem with the old version were (I think so - correct me if I'm wrong) the missing PPS/SPS-Informations within the stream (only sent once at the beginning?)

Hi,
I've got the same problem: when streaming mp4/h264 over RTP I only get audio at the recevier.

I tried tweaking on the -bf parameter as you said, but I discovered that I don't need to specify the -bf parameter at all, just re-encoding the mp4 file with ffmpeg (same container, audio and video codecs) made it streamable by VLC over RTP.

With mediainfo I could see the following difference among the two files:

SOURCE FILE (only audio at the recevier)
Format settings, CABAC: No
Format settings, ReFramaes: 1 frame

RE-ENCODED FILE (boht audio and video over RTP)
Format settings, CABAC: Yes
Format settings, ReFrames: 5 frame

Two questions:
1. Can anybody give a more detailed exaplanation while the re-encoded file could be streamed over RTP (maybe the CABAC setting is not really the issue)
2. I specified mux=ts as RTP module option, therefore I assume that VLC demuxes the mp4 and then remuxes the streams using mpget-ts, am I right? Indeed, VLC cannot stream mp4 over RTP as stated here: http://www.videolan.org/streaming-features.html

Thanks for any help!

[nicol@s]

Hi, guys!
Have you solved this problem??
I have the same problem - audio, but no video while streaming .mkv by rtsp
I have tried different versions of VLC. There are no any problems with streaming .avi, .mpeg4 and others. But there is a problem with streaming .mkv.
Now I have VLC 1.1.0, because I have tried to stream .mkv from Windows machine with this version and I have got a good result. Before this I tried VLC versions 1.1.12, 1.2.0...

The server is Debian.
uname - a

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Linux video 2.6.32-5-amd64 #1 SMP Mon Oct 3 03:59:20 UTC 2011 x86_64 GNU/Linux

I start streaming by this command on the server:

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cvlc -vvv /home/vlc/formula.mkv --sout '#transcode{vcodec=h264,vb=3000,fps=25,scale=1,acodec=mp4a,ab=128,channels=2,samplerate=48000,width=704,height=576}:rtp{sdp=rtsp://10.1.2.79:8554/vod}'

There are no errors in the log, only some warnings. The same warnings are present when I try to stream .avi, mpeg4... I think this warnings are not critical.
On the client machine I start VLC with rtsp://10.1.2.79:8554/vod and have audio, but no video.

I have found a lot of topics in videolan forum with the same problem, but havent`t found any solution.