GStreamer RTSP-Server transfering custom GstMeta data to the client - gstreamer

I need to share a custom Timestamp for each frame to the client. My idea was to add into the GstMeta a custom MetaData-Structure that shares the Timestamp to the client.
For sharing the video we are using the rtsp-server for GStreamer. Does anybody know if it is possible to transfer any kind of GstMeta data with that server?

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How do I stream audio files to my Icecast server running on an EC2 instance?

I am trying to loop audio from my Icecast server 24/7.
I have seen examples where people talk about storing their audio files on the EC2 instance or in an S3 bucket.
Do I also need a source client running on my EC2 Instance to be able to stream audio to the server? Or is there a way to play static files from Icecast?
Icecast and SHOUTcast servers work by passing a live audio stream from a source on to the users. You need something to produce a single audio stream in realtime from those source files.
The flow looks something like this:
Basically, you'll need to do everything you would in a normal radio studio, but automated. You'll stream the files from your bucket, play them to a raw audio stream, send that stream to your encoder to be compressed with the codec, and then sent to your streaming servers for distribution.
You can't simply push your audio files as-is to the Icecast server, for a few reasons:
Stream must be realtimeThe server doesn't really know or care about the timing of the stream. It takes the data its given and sends that off to the client. Therefore, if you push data faster than realtime, the server will attempt to deliver it to the client at this faster rate. Some clients will attempt to buffer this fast stream, but most will put backpressure on the stream, causing the TCP window to close, causing the client to eventually get far enough behind that the server drops the connection.
Consistent format is requiredChances are, your source files have varying sample rate, channel count, and even codec. Most clients are unable to take a change in sample rate or channel count mid-stream. I don't know of any client that supports a codec change mid-stream. (Theoretically possible with Ogg and Matroska/WebM, but yeah... not worth messing with.)
Stream should be free of ID3 tags and other file format cruftIf you simply PUT your files directly to your Icecast server, the output stream will contain more than just the audio data. At a minimum, you'd want to remove all that. Depending on your container format, you'll need to deal with timestamps as well.
Solutions
There are a handful of ways to solve this:
Radio automation softwareMany folks simply run something like RadioDJ on cloud-based servers. If you already have a radio station that uses automation, this might be a good solution. It can be expensive though, and not as flexible. You could even go as low as VLC or something for playout, but then you wouldn't have music transitions and what not.
Custom playout script (recommended)I use a browser engine, such as Chromium, and script my channels with normal JavaScript. From there, I take the output stream and pass it off to FFmpeg to encode and send to the streaming servers. This works really well, as I can do all my work in a language everybody knows, and I have easy access to data on cloud-hosted services. I can use the Web Audio API to mix and blend audio based on what's happening in realtime. As an alternative, there is Liquidsoap, but I do not recommend it these days as its language is difficult to deal with and it is not as flexible as a browser engine.

How to get audio data in a specific format in real time from a Twilio MediaStreamTrack?

I am using Twilio Programmable video, and trying to pipe remote participant's audio in real time to Google Cloud Media Translation client.
There is a sample code on how to use Google Cloud Media Translation client via microphone on here.
What I am trying to accomplish is that instead of using a microphone and node-record-lpcm16, I want to pipe what I am getting from Twilio's AudioTrack to Google Cloud Media Translation client. According to
this doc,
Tracks represent the individual audio, data, and video media streams that are shared within a Room.
Also, according to this doc, AudioTrack contains an audio MediaStreamTrack. I am guessing this can be used to extract the audio and pipe it to somewhere else.
What's the best way of tackling this problem?
Twilio developer evangelist here.
With the MediaStreamTrack you can compose it back into a MediaStream object and then pass it to a MediaRecorder. When you start the MediaRecorder it will receive dataavailable events which will be a chunk of audio in the webm format. You can then pipe those chunks elsewhere to do the translation. I wrote a blog post on recording using the MediaRecorder, which should give you a better idea how the MediaRecorder works, but you will have to complete the work to stream the audio chunks to the server to be translated.

Web LiveStreaming WebRTC and Sockets (Flask Backend)

I want to build a live streaming app.
My thought process:
Get the Video/Audio data from the
navigator.mediaDevices.getUserMedia(constraints); [client-streamer]
create rooms using sockets(Socket.IO or WebSockets from flask) [backend]
Send the data in 1 to the room members using sockets.
display the media on the client-side.
Is that correct? How should I do it?
how do I broadcast data to specific room members and not to everyone? (flask)
How to consistently send data from the streamer -> server -> room members. the stream is given from 1 is an object, where is the data?
any other better ideas will be great! thanks.
I need to implement the server-side by myself without help from libraries that will do the work for me.
Implementing a streaming platform is not trivial. Unfortunately, it is not as simple as emitting chunks received from the MediaRecorder with onndatavailable and forwarding them to users using a WebSocket server - this is not scalable nor efficient nor reliable.
Below are some strategies you can try for different types of scenarios:
P2P: If you want to have simple peer-to-peer streaming, you can use WebRTC to achieve that with a simple socket.io server for signaling purposes.
Conference: Here things start to get more complicated. You will need a media server if you want to be somewhat scalable. One approach is to route your stream to the users using an SFU or MCU. This will take care of forwarding/processing media to different peers efficiently.
Broadcast: Here things are also non-trivial. Common WebRTC-based architectures include ingesting the WebRTC stream and forward that to an HLS server which will let your stream chunks available for clients through a CDN, or perform RTP forwarding of the WebRTC stream, convert it to RTMP using something like FFmpeg and deliver it through Youtube Live or Twitch to leverage from their infrastructure.
Be aware that the last 2 items are resource-intensive and will certainly not be cheap to maintain.
Below are some open source projects that could help you along the way:
Janus
MediaSoup
AntMedia
Jitsi
Good luck!
Explaining all this is far beyond the scope of a Stack Overflow answer.
Here are a few hints:
You need to use the MediaRecorder API to capture compressed data from your gUM (getUserMedia) stream. MediaRecorder support is inconsistent between makes and models of browser. though.
It kicks a Blob into its onndatavailable handler every so often.
They're compressed as a webm data stream.
You can push those Blobs to a server with socket.io, and the server can turn around and push them to whatever clients you want to.
Playing the webm on the clients is tricky. You may, on some makes and models of browsers, be able to feed the webm stream to the Media Source API using appendBuffer(). But some browsers cannot consume the webm streams.
These webm streams are useless to a player without all their Blob data in order. You can't just start sending a new client the Blobs of the stream when they sign in; you have to restart the MediaRecorder.
(You may be able to make it work without a MediaRecorder restart if you send the first few k bytes of the stream to each new client before sending the current Blob. Extracting those bytes is an intricate programming job involving the ebml package to parse the webm stream and extract the prologue. I have not proven this concept.)
Because getting all this to work -- originator -- server -- viewer is such a pain in the xxx neck, you may want to investigate using something like mediasoup instead. It uses WebRTC transport rather than socket.io, and works cross-platform.

Stream Audio Via TCP in UE4

I am trying to build a Virtual Assistant in UE4. I need to somehow send my response from DialogFlow to UE4 for use in the Oculus Lipsync Plugin.
Basically, I have 3 media options for the response:
-16-Bit Linear PCM
-mp3
-Ogg Opus
I have a TCP Server and Client connection set up between a Python Script and UE4, so I can send data to and from easily.
I have my sequencing correct so one script waits for the full Byte Array to be sent via the socket etc.
Basically, I want to send the responses to each Query the user sends to DialogFlow INTO UE4 Via my TCP Socket, and be able to play and access that Audio within UE4.
I need to somehow stream the response from DialogFlow into UE4 as it gives me the responses.
Is what I'm trying to do even possible? I'm just trying to stream in Audio for use within UE4 and I am really struggling to get it working. Very annoying as this is the last piece of the puzzle I need to finish....
Please let me know if you have any advice or help you can offer!

Dynamically handle channels to publish to with Redis in C++

I have 2 applications (a GUI in javascript and another in C++) which need to communicate to each other.
The C++ application (server) contains multiple realtime sensor data which it has to stream to the GUI (client). The data is buffered and sent as a big chunk. The GUI simply renders the data and doesn't buffer it locally (current library renders relatively slow).
We want to use Redis where each channel is a sensor. On the client side the user can select which sensor has to be streamed. This requires to let the server somehow know which channels to publish to.
Now the question is more about performance and extensibility. Which scenario is best?
Publish all sensor data. +-30 sensors with data at max 64 bit. Each up to 10,000 samples streamed at up to 50hz. (This is maxing out absolutely everything, but does give a ballpark).
Store the channel names in Redis as a JSON object or namespaced keys. Listen for a set event server-side, get the channels and cache them and dynamically publish to the channels.
Same as above but get the channels during every cycle from Redis without listening to any set event.
Use a configuration channel where the client publishes the configuration (via JSON string) when it's changed. Server side we subscribe to the configuration channel and handle the new channels appropriately.
Something else. Please elaborate.
Try to use redis streams feature from recently released redis 5.0. If you are looking for performant C++ library, which supports redis streams try to use bredis, for example.