Fisheye Calibration

Fisheye Calibration configures video-fusion parameters for fisheye cameras, including fisheye distortion correction, distortion-parameter reuse, center-point configuration, five-face point calibration, result review, and saving.

The Fisheye Calibration page contains an image display area, a 3D model scene, a distortion-correction method selector, point calibration, configuration results, and fisheye calibration history.

Open Fisheye Calibration

1. Find a camera with the type Fisheye in the Camera List.

2. Click that camera's calibration action.

Open Fisheye Calibration.

3. On the Fisheye Calibration page, click Screenshot to capture the current frame. You can also click Video Frame to view the video before capturing it again.

Capture a fisheye screenshot.

Chessboard Screenshot Distortion Correction

1. Click the Distortion Correction step.

2. Select Chessboard Calibration from the Distortion Correction Method drop-down list.

Select Chessboard Calibration.

The left side provides a live-view placeholder. On the right, use Manual Screenshot to capture a video frame containing a chessboard held in front of the camera.

Capture a chessboard screenshot.

Screenshots are added to the screenshot list and show a recognition status.

View screenshot recognition status.

If a screenshot is marked for retake, click the delete button in the upper-right corner of the image, then capture it again.

Delete a screenshot marked for retake.

Retake a chessboard screenshot.

When there are enough screenshots—at least 15 containing a chessboard—click Distortion Correction.

Correct fisheye distortion.

The prototype requires 15 screenshots for distortion correction. In practice, ensure the chessboard is clear and complete and appears at different positions and angles.

Reuse Distortion Parameters

Choose Reuse Distortion Parameters from the correction-method drop-down list. A list of calibrated fisheye cameras appears; select a camera to reuse and confirm. Its distortion parameters are applied to the camera currently being calibrated.

Reuse distortion parameters from a calibrated fisheye camera.

Configure the Center Point

1. After distortion correction, proceed to Configure Center Point.

Configure the center point.

Click the center point in the 3D scene. Its longitude and latitude are updated at the same time.

Select the center point in the 3D scene.

3. After selecting the center point, click Save to proceed to point calibration.

Point Calibration

1. Click the Point Calibration step.

2. Start with the bottom face. Select the face; the image shows a highlighted quadrilateral. Adjust P0, P1, P2, and P3 in sequence.

Calibrate points on the bottom face.

Adjust points on the bottom face.

While annotating a face, its image is projected in real time in the scene on the right. Use the fit between the image and model to evaluate calibration quality.

Preview the face projection in the 3D scene.

Next, calibrate the Front face using the same point-selection steps.

Calibrate the Front face.

Next, calibrate the Rear face using the same point-selection steps.

Calibrate the Rear face.

Next, calibrate the Left face using the same point-selection steps.

Calibrate the Left face.

Next, calibrate the Right face using the same point-selection steps.

Calibrate the Right face.

After confirming the points, click Save.

Fine-tune translation, rotation, and scale in the 3D scene to align the image with the scene model.

Fine-tune fisheye calibration in the 3D scene.

Save Fisheye Configuration

• The Configuration Result area on the right displays fisheye calibration JSON and supports copying it.

Fisheye calibration configuration JSON.

• After you click Save, the fisheye camera status changes to Calibrated.