VLC setup for real time streaming with a webcam
Posted: 26 Jun 2019 16:28
Hi people, Good morning.
My name is Eliomar, I am a beginner with VLC and for that reason I would like to ask for a little help in streaming.
Since a week I am trying to stream my web cam over my local network in real time with no success.
I get the image of the webcam but with a latency that I would prefer to eradicate, the lowest latency that I have reached is approximately 1.5s, I would like to decrease it a little more at least below 1s.
Is it possible to decrease that latency below 1 second? I have read that VLC is a powerful video tool and for that reason i am trying to achieve this with that. Checking in other forums I have read too that I can use other video players to play the stream with a "more real time experience". But I would like to know if I can achieve that only with VLC on the server side (the one that sends the stream) and also in the client side (the one that receives the stream).
I am running VLC 3.0.4 vetinari.
Ubuntu 18.04 LTS in one machine, the one that sends the stream.
windows 10, in the client machine.
My current setup on the server side are:
1. live-caching: 300ms
2. fps: 30
3. I am using RTSP protocol and the TS container (Video h264 + mp3).
when I am going to start the stream I check the next line
:sout=#transcode{vcodec=h264,vb=800,acodec=mpga,ab=128,channels=2,samplerate=44100,scodec=none}:rtp{sdp=rtsp://:12345/stream.ts} :no-sout-all :sout-keep
I tried to decrease the "vb" parameter with a little improvement on the latency (with a lower size than with 800 but that's no problem, I don't mind the size of the image) but the streaming on the client side tends to break after less than a minute.
Besides that? cold you explain me what is that parameter? what does it do? the "vb" parameter and the "ab" parameter?.
On the client side I have the following setup
1. network-caching: 300ms (I decreased, since the default value is 1000ms, and I Perceive an imporvement on the latency, the one of 1.5s, but sometimes the screen goes into green or gray, What does it means a green or gray screen?)
2- In the tool preferences I have tried with different post-processing levels, but the result is the same, i.e.: with post-processing level 4 i get the same latency than with 6, besides the image is worse than with post-processing level 6. So I understand that's not the problem, that make me think that the problem may be on the server side on any setup.
Besides that I have changed some streaming setup like the Stream output muxer cahing (ms).
That is in, tool --> preferences --> all settings --> streaming output
which i changed to 500ms from the default that was 1500ms but i did not get any improvement on the latency.
I would like to know if I am missing something? there is any other configuration parameter that I am missing? should I test with other video players and measure the latency of the streaming?
I also have tried the streaming between two PCs on the same local network (taking off any internet connection problem).
And I tried even sending and receiving on the same PC (taking off any local network problem) and I am getting approximately the same latency of 1.5s.
sometimes, even the tests on the same computer were better because between the two PCs the screen became green after a few seconds or simply started on green and the streaming was not able to be seen.
I would appreciate all the help with this please, or if you can send me any documentation that can help me to solve this issue I will appreciate that.
Also if you want to send documentation about streaming that is not contemplated on the VLC wiki I will appreciate too. I like the media world I would like to learn alot of it.
Well, without nothing more to say. Thanks in advance for all the help guys.
Regards.
Eliomar.
My name is Eliomar, I am a beginner with VLC and for that reason I would like to ask for a little help in streaming.
Since a week I am trying to stream my web cam over my local network in real time with no success.
I get the image of the webcam but with a latency that I would prefer to eradicate, the lowest latency that I have reached is approximately 1.5s, I would like to decrease it a little more at least below 1s.
Is it possible to decrease that latency below 1 second? I have read that VLC is a powerful video tool and for that reason i am trying to achieve this with that. Checking in other forums I have read too that I can use other video players to play the stream with a "more real time experience". But I would like to know if I can achieve that only with VLC on the server side (the one that sends the stream) and also in the client side (the one that receives the stream).
I am running VLC 3.0.4 vetinari.
Ubuntu 18.04 LTS in one machine, the one that sends the stream.
windows 10, in the client machine.
My current setup on the server side are:
1. live-caching: 300ms
2. fps: 30
3. I am using RTSP protocol and the TS container (Video h264 + mp3).
when I am going to start the stream I check the next line
:sout=#transcode{vcodec=h264,vb=800,acodec=mpga,ab=128,channels=2,samplerate=44100,scodec=none}:rtp{sdp=rtsp://:12345/stream.ts} :no-sout-all :sout-keep
I tried to decrease the "vb" parameter with a little improvement on the latency (with a lower size than with 800 but that's no problem, I don't mind the size of the image) but the streaming on the client side tends to break after less than a minute.
Besides that? cold you explain me what is that parameter? what does it do? the "vb" parameter and the "ab" parameter?.
On the client side I have the following setup
1. network-caching: 300ms (I decreased, since the default value is 1000ms, and I Perceive an imporvement on the latency, the one of 1.5s, but sometimes the screen goes into green or gray, What does it means a green or gray screen?)
2- In the tool preferences I have tried with different post-processing levels, but the result is the same, i.e.: with post-processing level 4 i get the same latency than with 6, besides the image is worse than with post-processing level 6. So I understand that's not the problem, that make me think that the problem may be on the server side on any setup.
Besides that I have changed some streaming setup like the Stream output muxer cahing (ms).
That is in, tool --> preferences --> all settings --> streaming output
which i changed to 500ms from the default that was 1500ms but i did not get any improvement on the latency.
I would like to know if I am missing something? there is any other configuration parameter that I am missing? should I test with other video players and measure the latency of the streaming?
I also have tried the streaming between two PCs on the same local network (taking off any internet connection problem).
And I tried even sending and receiving on the same PC (taking off any local network problem) and I am getting approximately the same latency of 1.5s.
sometimes, even the tests on the same computer were better because between the two PCs the screen became green after a few seconds or simply started on green and the streaming was not able to be seen.
I would appreciate all the help with this please, or if you can send me any documentation that can help me to solve this issue I will appreciate that.
Also if you want to send documentation about streaming that is not contemplated on the VLC wiki I will appreciate too. I like the media world I would like to learn alot of it.
Well, without nothing more to say. Thanks in advance for all the help guys.
Regards.
Eliomar.