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Configure cameras

Detect the USB cameras, set one shared capture configuration, and order them — the first camera is the extrinsic anchor.

Work in progress

Scaffold page — to be expanded with screenshots from the Camera Setup step.

What happens here​

The calibration-service enumerates connected USB cameras (V4L2) and publishes a live preview for each over LiveKit. In the web app's Camera Setup view you can:

  • Detect / re-detect the connected cameras and confirm each is streaming.
  • Set the capture configuration — resolution, frame rate and resize factor. These are shared by all cameras and only offer the modes common to every detected camera.
  • Order the cameras by drag-and-drop. The camera at the top (index 0) is the anchor used to chain extrinsic poses.

Capture configuration​

Because the rig is calibrated as one system, resolution and frame rate are picked once and applied to every camera — the selectors only offer modes supported by all detected cameras. Frame rate follows a 60 / 30 / 15 ladder, capped by each camera's native maximum for the chosen resolution.

Resolution vs. resize factor​

Two independent controls change how many pixels calibration works on — but they trade off very differently:

  • Resolution selects the camera's native capture mode. A lower mode costs less compute, but beware: most USB cameras produce a lower resolution by cropping the sensor, not by scaling it down — so dropping the resolution often narrows the field of view. You gain speed but lose coverage.
  • Resize factor (s) is a software downscale (cv2.resize) applied to the captured frame — 1, 0.75, 0.5, ⅓ or 0.25. It keeps the full field of view and simply lowers the pixel count, trading fine detail for compute.

So to cut compute without losing field of view, prefer lowering the resize factor over dropping to a smaller native resolution.

Whichever you choose, the resulting calibration resolution is recorded so intrinsics stay consistent with the images they were computed from: the stored K corresponds to that resolution, and K_out = s·K is written on export.

→ Reference: Calibration output files