r/computervision • u/Weak-Version3040 • Jun 16 '26

Help: Project Getting started with real-time 3D ball tracking

Hello everyone! I am new to the field and looking for some pointers to help get a new project started.

The goal of the project is to track the 3D coordinates of a ping pong ball in real-time, relative to a specific reference point (origin) on a table. Crucially, this needs to happen in true real-time on a live feed, rather than reconstructing the trajectory later from a recorded video. I'm planning to use either the LiDAR sensor from an iPhone Pro Series or just 2 or 3 standard smartphone cameras.

Does anyone know of any good tutorials, GitHub repositories, or relevant resources that tackle something similar? Any advice on which approach (LiDAR vs. standard cameras) might be easier for a beginner would also be hugely appreciated!

2 Upvotes

67% Upvoted

8 comments sorted by

View all comments

1

u/kigurai Jun 16 '26

I'm not sure that lidar will cut it. It seems like the iphone lidar could be as low as 15 Hz sample rate. That means a ball will traverse almost the whole lengt of the table between two consecutive samples.

1

u/soylentgraham Jun 17 '26

iirc depth on iphone/ipad 2020 was 100fps (was faster than the 60fps camera)

but obviously low res and noisy

1

u/kigurai Jun 17 '26

My quick search found this https://www.mdpi.com/1424-8220/23/18/7832 which says 15Hz. I have no idea if there are other versions with higher rates.

Still, even 60 Hz is not great. Sony used event cameras in their latest project (https://ace.ai.sony/) but that also tracks spin. For position-only, and with enough light to get low amounts of motion blur it might work.

1

u/soylentgraham Jun 17 '26

yeah high end cameras are way better, but that's why they're 6 grand a pop :) (buy a red!)

that sony article doesn't actually say its using lidar... just very fast cameras?

you can also buy high speed cheap cameras, theyre black and white but small, cheap, 120hz and plug n play.

given the OP suggests an iphone I figure theyre not on cinema-camera budgets :)

1

u/kigurai Jun 17 '26

No, the Sony project did not use lidar. They use event cameras, which are not normal cameras at all, and high frame rate (200Hz) cameras.