Recording Multiple Cameras to Single SVO

Software ROS2
,
1

I have a robot with two zedxm cameras and a stereolabs orin mini carrier board (16GB model).
I’m running the zed-ros2-wrapper with two composable zed nodes spun up in the same zed container.

I’m currently bagging non-visual data to a ros2 bag while logging to separate SVO files (one per zed node) the camera data.

I’m currently using the following SVO params for each of the zed nodes:

svo:
use_svo_timestamps: false # Use the SVO timestamps to publish data. If false, data will be published at the system time.
publish_svo_clock: false # [overwritten by launch file options] When use_svo_timestamps is true allows to publish the SVO clock to the /clock topic. This is useful for synchronous rosbag playback.
svo_loop: false # Enable loop mode when using an SVO as input source. NOTE: ignored if SVO timestamping is used
svo_realtime: false # if true the SVO will be played trying to respect the original framerate eventually skipping frames, otherwise every frame will be processed respecting the pub_frame_rate setting
play_from_frame: 0 # Start playing the SVO from a specific frame
replay_rate: 1.0 # Replay rate for the SVO when not used in realtime mode (between [0.10-5.0])

My assumption is that I’ll be able to correlate frames and other data between the cameras since they are both using the system clock. Furthermore, I assume I’ll be able to correlate zed data with my ros2 bag data since it is also using system time.
Is this assumption true?

I would ideally like to record both cameras in the same SVO.
When I’ve tried this naively by just passing the same file to each of the zed nodes, sometimes they crash and when they don’t, I’m only able to play back one camera using both the zed wrapper and the zed CLI (e.g. ZED_Explorer or ZED_Depth Viewer).
Is it possible to write multiple cameras to one SVO?

2

This is correct, remember to set use_svo_timestamps to true when playing the SVO in this case.

This is not possible.