For a research purpose, I developed and app to control a wheeled mobile robot using the gyro and the accelerometer of an iPhone. The robot has a IP address, and I control it by sending messages through a socket. Since the robot has to be controlled from anywhere in the world, I mounted a camera on top of it. I tried to stream the video from the camera using the http live streaming protocol and vlc, but the latency is too high (15-30sec) to properly control it.
Now, vlc has the possibility to stream over udp or http, but the point is how do I decode the stream on the iPhone? How should I treat the data coming into the socket in order to visualize them as a continuous live video?
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I'm trying to isolate video and audio and am able to control the video feed from the caller side, however, unable to turn off the local video stream on the remote side since its an audio call. Any suggestions on how to isolate the video and audio feeds. It doesn't work just by removing the streams by getting the getStream.
I have multiple Raspberry Pi Devices with the native camera in my home and office (PUBLISHERS). - Publisher(Pi) they are on a local network behind a firewall/router and connected to the internet.
I have an EC2 webserver (BROKER). It is publicly accessible over a public IP Address.
I have an Android App on my phone. It has internet connectivity through a 4G Network. (SUBSCRIBER/CONSUMER/CLIENT)
I am trying to view the live feed of each of the raspberry cameras on my Android app. The problem is more conceptual than technical. I am unable to decide what should be the right approach and most efficient way to achieve this in terms of costs and latency.
Approaches, I have figured out based on my research on this:-
Approach 1:
1. Stream the camera in RTSP / RTMP in the pi device via raspvid/ffmpeg
2. Have a code in the pi device that reads the RTSP stream saves it to AWS S3
3. Have a middleware that transcodes the RTSP stream and saves it in a format accessible to mobile app via S3 url
Approach 2:
1. Stream the camera in RTSP / RTMP in the pi device via raspvid/ffmpeg
2. Have a code in the pi device that reads the RTSP stream pushes it to a remote frame gathering (ImageZMQ) server. EC2 can be used here.
3. Have a middleware that transcodes the frames to an RTSP stream and saves it in a format on S3 that is accessible to the mobile app via pubicly accessible S3 URL
Approach 3:
1. Stream the camera in WebRTC format by launching a web browser.
2. Send the stream to a media server like Kurento. EC2 can be used here.
3. Generate a unique webrtc pubicly accessible url to each stream
4. Access the webrtc video via mobile app
Approach 4:
1. Stream the camera in RTSP / RTMP in the pi device via raspvid/ffmpeg
2. Grab the stream via Amazon Kinesis client installed on the devices.
3. Publish the Kinesis stream to AWS Cloud
4. Have a Lambda store to transcode it and store it in S3
5. Have the mobile app access the video stream via publicly accessible S3 url
Approach 5: - (Fairly complex involving STUN/TURN Servers to bypass NAT)
1. Stream the camera in RTSP / RTMP in the pi device via raspvid/ffmpeg
2. Grab the stream and send it a to mediaserver like gstreamer. EC2 can be used here.
3. Use a live555 proxy or ngnix RTMP module. EC2 can be used here.
4. Generate a unique publicly accessible link for each device but running on the same port
5. Have the mobile app access the video stream via the device link
I am open to any video format as long as I am not using any third-party commercial solution like wowza, antmedia, dataplicity, aws kinesis. The most important constraint I have is all my devices are headless and I can only access them via ssh. As such I excluded any such option that involves manual setup or interacting with desktop interface of the PUBLISHERS(Pis). I can create scripts to automate all of this.
End goal is I wish to have public urls for each of Raspberry PI cams but all running on the same socket/port number like this:-
rtsp://cam1-frontdesk.mycompany.com:554/
rtsp://cam2-backoffice.mycompany.com:554/
rtsp://cam3-home.mycompany.com:554/
rtsp://cam4-club.mycompany.com:554/
Basically, with raspvid/ffmpeg you have a simple IP camera. So any architecture applicable in this case would work for you. As example, take a look at this architecture where you install Nimble Streamer on your AWS machine, then process that stream there and get URL for playback (HLS or any other suitable protocol). That URL can be played in any hardware/software player upon your choice and be inserted into any web player as well.
So it's your Approach 3 which HLS instead of WerRTC.
Which solution is appropriate depends mostly on whether you're viewing the video in a native application (e.g. VLC) and what you mean by "live" -- typically, "live streaming" uses HLS, which typically adds at least 5 and often closer to 30 seconds of latency as it downloads and plays sequences of short video files.
If you can tolerate the latency, HLS is the simplest solution.
If you want something real-time (< 0.300 seconds of latency) and are viewing the video via a native app, RTSP is the simplest solution.
If you would like something real-time and would like to view it in the web browser, Broadway.js, Media Source Extensions (MSE), and WebRTC are the three available solutions. Broadway.js is limited to H.264 Baseline, and only performs decently with GPU-accelerated canvas support -- not supported on all browsers. MSE is likewise not supported on all browsers. WebRTC has the best support, but is also the most complex of the three.
For real-time video from a Raspberry Pi that works in any browser, take a look at Alohacam.io (full disclosure: I am the author).
I'm trying to sent some audio stream from my browser to some server(udp, also try websockets).
I'm recording audio stream with webrtc , but I have problems with transmitting data from a nodeJS client to the my server.
Any idea? is it possible to send audio stream to the server using webrtc(openwebrtc)?
To get audio from the browser to the server, you have a few different possibilities.
Web Sockets
Simply send the audio data over a binary web socket to your server. You can use the Web Audio API with a ScriptProcessorNode to capture raw PCM and send it losslessly. Or, you can use the MediaRecorder to record the MediaStream and encode it with a codec like Opus, which you can then stream over the Web Socket.
There is a sample for doing this with video over on Facebook's GitHub repo. Streaming audio only is conceptually the same thing, so you should be able to adapt the example.
HTTP (future)
In the near future, you'll be able to use a WritableStream as the request body with the Fetch API, allowing you to make a normal HTTP PUT with a stream source from a browser. This is essentially the same as what you would do with a Web Socket, just without the Web Socket layer.
WebRTC (data channel)
With a WebRTC connection and the server as a "peer", you can open a data channel and send that exact same PCM or encoded audio that you would have sent over Web Sockets or HTTP.
There's a ton of complexity added to this with no real benefit. Don't use this method.
WebRTC (media streams)
WebRTC calls support direct handling of MediaStreams. You can attach a stream and let the WebRTC stack take care of negotiating a codec, adapting for bandwidth changes, dropping data that doesn't arrive, maintaining synchronization, and negotiating connectivity around restrictive firewall environments. While this makes things easier on the surface, that's a lot of complexity as well. There aren't any packages for Node.js that expose the MediaStreams to you, so you're stuck dealing with other software... none of it as easy to integrate as it could be.
Most folks going this route will execute gstreamer as an RTP server to handle the media component. I'm not convinced this is the best way, but it's the best way I know of at the moment.
How can I reverse engineer the video stream URL by looking at the network interface/traffic?
I have a Panasonic Lumix DMC-FT6, which has a "wifi mode". I have the iOS Panasonic Image App. I can setup a HTTP Proxy between the two (using Charles) and see the communication. I can see some "UDP 17" traffic between the iPhone by watching the interface via the method How do you monitor network traffic on the iPhone? using Wireshark.
My end goal is to enter a stream URL in VLC and see the video stream.
Unfortunately there is no open source information on this that I can see.
What is the protocol most likely to be (for a consumer camera)?
What traits can I look for?
Are there any obvious URLs worth trying?
I'm beginner developer.
And I don't speak engilsh very well. sorry
I want to broadcast live video from iPhone camera like iphone video call.
In this case, which do I choice better, hls or dss.
so, what's the functional difference HLS and DSS.
Can hls broadcast live video from iphone camera to another iphone?
Darwin Streaming Server is for RTSP streaming. HLS is a streaming technology based on using HTTP server for hosting the content.
iPhone to iPhone video isn't well served by either technology. It's possible to use an iPhone camera to capture video, upload it to a server, package it for HLS and serve it to the client viewers. This is very high latency (around 10-30 seconds), so it's likely not suitable for you.
If you want 1-to-1 messaging, you're probably better off using a real-time system like RTP, which is what's used by FaceTime and video calling programs.