How to split an image from a single 4pin ETH camera to two ETH devices on a drone

Hello Mindhive.
I have a specific project on which i am using an ETH Topotek camera and i need to be able to send the image at the same time on the Cubepilot Herelink airunit ETH port and on a raspberry that will do some image processing. I would appreciate your input.
I have very limited ETH knowledge so please dont find my question silly.
In our office i just know that we have a server for multiple reassons as also a camera system which they are both connected on a switch. from any station within our office anyone is capable to access both at any time, even multiple stations at any time. I have seen this product: SwitchBlox for Ardupilot and i was wondering if this would do the trick.

SwitchBlox for Ardupilot is a dumb connector adapter and so cannot do anything fancy when it comes to data. In other words, it’s not what you need.

What you’re looking to do is access a camera stream on multiple devices. I can think of two ways of doing this, using multicast streaming or using RTSP streaming. If you’re new to ethernet, that might be a challenge for you.

The camera you are using will have to support this; looking at topotek cameras, I can see RTSP is supported on this camera, not sure if it is on the others.

I’m not sure how your office setup is working, but if it’s using a server, then it’s possible that the server is implementing the multicast or RTSP stream and then broadcasting that to other devices. Doing that on our products isn’t possible because none of our products are routers.

Camera in question supports RTSP. As i said im not any good when it comes to ETH. So my question is simple. I have a single ETH output (Camera) which uses 4 pins and i have a Herelink V1.1 Airunit and also a Raspberry Pi4. If it were anything else splitting the cable to a Y it would not be an issue, but with ETH im guessing it needs something that will act as a switch and let everything be connected together.

Splitting the cable to a Y would work if it was a CAN communication bus which is multidrop (multiple nodes on the same wire). But ethernet, along with many other protocols, is point-to-point, meaning you can’t simply split the wires to connect one device to two…

There is a way of kinda doing that, by using a switch and connecting your camera to one port, then your raspberry pi to another port. Then you could use a port mirroring feature to send a copy of all the data received from the camera into a third port, to which you could connect your herelink.

You could do this but you’d still have to deal with the fact that your camera is sending to the IP address of your raspberry Pi, and so the mirrored traffic sent to the herelink may just be dropped by the herelink (I’m actually not sure what would happen in that case).

The solutions such as RTSP and multicast were designed to allow this kind of thing, streaming from one device to multiple, but they require a bit of knowledge to setup. In other words, I can’t really give you a simple answer here, you’re going to have to study RTSP and speak with your camera manufacturer about how to setup RTSP.

Then, you’re going to need to find a switch to connect all the devices to. We have run a test with SwitchBlox Rugged using RTSP and it works. Take a look at the last post on the thread below.

Apologies, this is not a simple answer, but this isn’t a beginner level thing.