ZED X Hardware Synchronization

Hardware ZED X
1

Hi folks,

I have an AGX Orin running Jetpack 6 with SDK 4.2.1, with a quad capture card, with 4 ZED Xs connected to it.

In my program I have 4 threads reading the 4 cameras, I’m running at 15fps. I’m storing the image timestamps using the camera.getTimestamp(TIME_REFERENCE::IMAGE); function after each camera.grab() call.

I was under the impression that the ZED X’s connected to the capture card should capture synchronized frames within 100us automatically (meaning without any specific setup on my part), but when comparing the timestamps of my images they are off by up to 15ms.

Is this expected? Am I using the wrong method of getting the image timestamp?

2

Hi @Waelyn
the timestamp is associated with the data as soon as it’s received by the deserializer, not when it’s captured. This means that you can expect a little difference between them.
The difference is good as long as it’s minor than the grab period.

Please note that from an electronics point of view, the CMOS sensors acquire the data simultaneously with a minimal difference in the order of microseconds.