I'm implementing a solution for listening to on-going calls inside a LAN network.
Is there a way to provide WebRTC the ip address and port as to where an RTP stream is coming? All I want to do is to get that RTP stream directly streamed to the possible listeners of the call through WebRTC.
I'm not sure if it's feasible but I think it is given how WebRTC has evolved since the past months.
I've been looking around but I've got no luck on this.
The WebRTC RTP stream is encrypted with keys that are exchanged through DTLS. You cannot get the raw RTP stream from a WebRTC peer or even feed it a raw stream without some mediary system to handle the webrtc peerconnection, certificate exchange, and rtp encryption.
The only way to do what you want is to have a breaker or a gateway. An example of such a gateway is the janus-gateway though it is definitely not your only option.
Related
I have a simple application in c# that opens an RTSP session and sends the appropriate commands like DESCRIBE, SETUP, etc to control an RTP data stream.
My questions is this: does the TCP session (for the RTSP communication) have to stay open while streaming the data over RTP? Without going into details as to why, I'd like to be able to close the RTSP session after the RTP streaming is setup.
RFC 7826 Real-Time Streaming Protocol Version 2.0
A persistent connection is RECOMMENDED to be used for all
transactions between the server and client, including messages for
multiple RTSP sessions. However, a persistent connection MAY be
closed after a few message exchanges. For example, a client may use
a persistent connection for the initial SETUP and PLAY message
exchanges in a session and then close the connection. Later, when
the client wishes to send a new request, such as a PAUSE for the
session, a new connection would be opened. This connection may be
either transient or persistent.
So no, it is not required to be open while streaming data.
The short answer is yes you must keep the rtsp socket open.
If the stream is over TCP the RTP packet travels over the socket of the RTSP session. If the stream is over UDP the socket is used by the server to know if it should keep sending packet to the client because the UDP packet transmission does not have any feedback if the client is still alive.
Edited:
I think the answer marked correct is actually incorrect. In general, the cameras implement the RTSP protocol version 1 not version 2. In the 10 years that I have of experience in video surveillance systems I have found that several models of cameras stop sending RTP packets after closing the RTSP session socket .
I've successfully set up Asterisk on my server using the res_pjsip Hello World configuration from their wiki, and I want to be able to forward the RTP data to a Node.JS app, which can interpret RTP. I've heard about directmedia and directrtpsetup (see this stackoverflow) but I'm not sure if that's what I want. So my question is this:
Should I use directmedia / directrtpsetup to send voice data to my Node.JS app, or should I use some sort of Asterisk functionality to forward RTP packets? If the latter, how can Asterisk forward just the voice data?
I can clarify if needed, but hopefully this is more specific than my last questions. Thanks!
UPDATE: Having poked around Asterisk docs and messing with Wireshark, I think I have two options.
Figure out if there's a channel driver for Asterisk that just sends RTP, without any signaling, or
Capture the RTP stream with Wireshark or something and send the packets to the Node.JS app, and inject the return packets into the RTP stream.
Asterisk is PBX. It not suitable to "redirect rtp data"
No, there are no reason in having channel driver "without signalling". For what anyone can use it? How to determine call started if "no signaling"? It will be useless.
You can write such app in c/c++ or use other soft designed to be traffic capture: libpcap, tcpdump etc.
You also can use audio staff: libalsa, jack.
Best option however will be create or find full featured sip client and use it.
I am in search of a server software which can stream different audios to a different clients.
For example every client will be able to create his own playlist and the server will stream it
Any help will be appreciated
You can check flash which has support for RTMP to stream audio real time using client server & RTMFP which works over peer to peer technology. You can use RTMFP in case peer is directly reachable else use RTMP. There is a open source red5 media server which also has support for RTMP protocol.
I want to use an IP camera with webrtc. However webrtc seems to support only webcams. So I try to convert the IP camera's stream to a virtual webcam.
I found software like IP Camera Adapter, but they don't work well (2-3 frames per second and delay of 2 seconds) and they work only on Windows, I prefer use Linux (if possible).
I try ffmpeg/avconv:
firstly, I created a virtual device with v4l2loopback (the command was: sudo modprobe v4l2loopback). The virtual device is detected and can be feed with a video (.avi) with a command like: ffmpeg -re -i testsrc.avi -f v4l2 /dev/video1
the stream from the IP camera is available with: rtsp://IP/play2.sdp for a Dlink DCS-5222L camera. This stream can be captured by ffmpeg.
My problem is to make the link between these two steps (receive the rstp stream and write it to the virtual webcam). I tried ffmpeg -re -i rtsp://192.168.1.16/play2.sdp -f video4linux2 -input_format mjpeg -i /dev/video0 but there is an error with v4l2 (v4l2 not found).
Does anyones has an idea how to use an IP camera with webRTC?
Short answer is, no. RTSP is not mentioned in the IETF standard for WebRTC and no browser currently has plans to support it. Link to Chrome discussion.
Longer answer is that if you are truly sold out on this idea, you will have to build a webrtc gateway/breaker utilizing the native WebRTC API.
Start a WebRTC session between you browser and your breaker
Grab the IP Camera feed with your gateway/breaker
Encrypt and push the rtp stream to your WebRTC session from your RTSP stream gathered by the breaker through the WebRTC API.
This is how others have done it and how it will have to be done.
UPDATE 7/30/2014:
I have experimented with the janus-gateway and I believe the streaming plugin does EXACTLY this as it can grab an rtp stream and push it to an webrtc peer. For RTSP, you could probably create RTSP client(possibly using a library like gstreamer), then push the RTP and RTCP from the connection to the WebRTC peer.
Janus-gateway recently added a simple RTSP support (based on libcurl) to its streaming plugins since this commit
Then it is possible to configure the gateway to negotiate RTSP with the camera and relay the RTP thought WebRTC adding in the streaming plugins configuration <prefix>/etc/janus/janus.plugin.streaming.cfg
[camera]
type = rtsp
id = 99
description = Dlink DCS-5222L camera
audio = no
video = yes
url=rtsp://192.168.1.16/play2.sdp
Next you will be able to access to the WebRTC stream using the streaming demo page http://..../demos/streamingtest.html
I have created a simple example transforming a RTSP or HTTP video feed into a WebRTC stream. This example is based on Kurento Media Server (KMS) and requires having it installed for the example to work.
Install KMS and enjoy ...
https://github.com/lulop-k/kurento-rtsp2webrtc
UPDATE 22-09-2015.
Check this post for a technical explanation on why transcoding is just part of the solution to this problem.
If you have video4linux installed, the following command will create a virtual webcam from an rtsp stream:
gst-launch rtspsrc location=rtsp://192.168.2.18/play.spd ! decodebin ! v4l2sink device=/dev/video1
You were on the right track, the "decodebin" was the missing link.
For those who would like to get their hands dirty with some native-WebRTC, read on...
You could try streaming an IP camera’s RTSP stream through a simple ffmpeg-webrtc wrapper: https://github.com/TekuConcept/WebRTCExamples .
It uses the VideoCaptureModule and AudioDeviceModule abstract classes to inject raw media. Under the hood, these abstract classes are extended for all platform-specific hardware like video4linux or alsa-audio.
The wrapper uses the ffmpeg CLI tools, but I don’t feel it should be too difficult to use the ffmpeg C-libraries themself. (The wrapper relies on transcoding, or decoding the source media, and then letting WebRTC re-encode with respect to the ICE connections’ requirements. Still working out pre-encoded media pass-through.)
Actually our camera can support webrtc. It uses ip camera with h5, from P2P tramsmitting, and two way talk for ip camera with web browser! The delay is only 300ms!
I have been using UDP sockets to send and receive voice through RTP packetization. It is pretty straightforward. I just send my mic voice signals ( that are encoded ) over IP using User Datagram socket , and on the other end i receive the UDP-RTP packets and decode them to be able to play them on my speakers.
I have been searching on internet for a while to find a way to start up a session using UDP sockets. What i want to to is to a Handshake-like process between two ends of my conversation and after the requests were acknowledged the media layer ( which i described in first paragraph ) would fire and start sending voice.
I have not been able to find any tutorials on session request using UDP sockets but i suppose it shouldnt be impossible.( one user sends a request to build a session and if the other user confirms media layer starts)
Has anyone done something like this before? any info is welcome.
Firstly, UDP is a connectionless, unreliable protocol, you won't find anything like handshaking for negotiating connection i.e no session management. But, to transport RTP packets it's not a good idea to use tcp, it lacks realtime feature, so you have to stick with UDP. Now, to overcome the signaling problem you can use protocols like. SIP. It's standard signaling protocol used in VOIP. SIP initiates a connection before sending RTP packets. To properly use SIP and RTP you might have to take help of another protocol called SDP, which tells which port to use for transmitting RTP and other various info. You can get more info about these techniques here. Hope this will helps!