sl_open_camera crashes in self-calibration (LU32f) instead of returning error on low USB bandwidth

[arghhhhh]

Preliminary Checks

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• This issue is not a question, feature request, or anything other than a bug report directly related to this project.

Description

When a ZED camera is connected to a USB port with insufficient bandwidth, sl_open_camera() (via the Unity wrapper) crashes the process instead of returning a recoverable error code. The crash occurs during the retry logic after an initial Camera Open Internal Error: 1893.

Steps to Reproduce

Reproduction

1. Connect a ZED camera to a USB port with limited bandwidth (e.g., shared internal laptop hub)
2. Open camera via Unity plugin or ZED Diagnostic tool
3. Process crashes instead of returning an error

Switching to a Thunderbolt port with full bandwidth resolves the issue — confirming this is a bandwidth-triggered crash, not a calibration data issue.

Notes

• ZED Explorer and ZED Depth Viewer work on the same port (they likely use a simpler init path)
• ZED Diagnostic also crashes at the "Camera Test" step on the same port
• Crash is identical across SDK versions 5.1, 5.2.1, and 5.2.2
• The cameraDisableSelfCalib init parameter does NOT prevent this crash, since the self-calibration runs internally during sl_open_camera

Expected Result

sl_open_camera should return ERROR_CODE::LOW_USB_BANDWIDTH (or similar) so the application can handle it gracefully.

Actual Result

1. SDK logs [ZED][ERROR] [ZED] Camera Open Internal Error: 1893
2. SDK logs [Init] Failed to open camera. Trying to re-open for 5 seconds.
3. During retry, the process crashes in sl_update_self_calibration → slutils::cv::hal::LU32f (null/uninitialized data passed to LU decomposition)

ZED Camera model

ZED2i

Environment

- ZED SDK: tested on 5.1, 5.2.1, 5.2.2
- Unity: 2022.3.62f2
- Unity Plugin: com.stereolabs.zed v5.2.1 (git), 5.1
- OS: Windows 11 Pro 10.0.26200
- GPU: NVIDIA GeForce RTX 4080 Laptop GPU, driver 32.0.15.9579
- Camera serial: 39748971

Anything else?

The crash appears to happen because the retry attempts self-calibration with partially initialized camera state.

Stack Trace

sl_unitywrapper!sl_update_self_calibration
sl_unitywrapper!sl_open_camera
sl.ZEDCamera:dllz_open
ZEDManager:OpenZEDInBackground```

[Mars-Wave]

I can confirm this is also the case on RTX A5000 and A4000 graphics cards with 59X drivers on windows IoT Enterprise servers. Zed Diagnostics crashes without explaining the issue on the last step, testing the zed camera

[Mars-Wave]

from zed 5.0.0 throughout all versions until today