Output Camera Data in ROS2 (Pointcloud camera)


I was wondering if there was a way to get data sent from the RGB and Depth data sent out of Unity via ROS2? I know how to establish a ROS2 connection, and I have played with RGB and Depth capture in the perception module. However, I am not sure how to directly connect to a camera's output and send that data using ROS2.

1 Like

To clarify, do you want to send image data from a camera to Unity via ROS2 or first receive camera data directly in Unity and send it over ROS2 ?

Receive Camera data from Unity and send it to ROS2. I will need to send 2 types of data, RGB and depth. I am making some progress on both, but have hit a few roadblocks. I think I can solve the RGB data transfer with a previous answer I found on the forum, but if you have any insight it would be helpful. The depth data (point cloud) is a whole different challenge. I am trying to do things such as using the depth buffer data in a custom shader that gets it's own render pass, but so far that method is restricting me to 0-255 8bit data since the color channels are 0-255. Is there a way to get the depth buffer info out of of shadergraph and read it in a c# script?

I have determined a method of getting depth/pointcloud data out of unity fairly efficiently. The method involves creating a custom shader that writes the depth buffer to the R color channel. Use this to create a custom material where color values equal distance from the camera. Assign that material as a material override in a render texture and assign the depth camera output to the render texture. Then since you have the depth at each pixel, you can calculate a 3D pointcloud from your camera's view.

Now it is extremely intensive to calculate the location for every pixel (even for resolution as low as 640x480). To deal with this, I am processing within an IJobParallelFor job structure to parallelize the process. I was able to get a camera sending pointcloud data out via ROS2 at a rate of 15Hz with my simulation running roughly around 60Hz. There is a small stutter, but not enough to be an issue.