How to Check Camera Intrinsics

Camera intrinsics refer to the internal parameters of the camera, which are used to describe the internal optical characteristics and geometric structure of the camera and are important in the imaging process. Only when the intrinsics are accurate can the calculated coordinates of each point be accurate.

When image quality deteriorates, distortion becomes severe, or measurement accuracy is low, you can use the camera intrinsic check tool to inspect the camera intrinsics. If the intrinsics are not qualified, you can recalibrate them.

Preparations

Before checking the intrinsics, prepare the calibration board that came with the camera and follow these steps:

  1. Place the calibration board within the camera’s field of view.

  2. Capture a 2D image and point cloud of the calibration board. Ensure that the captured images meet the following standards. If the requirements are not met, please adjust the position of the calibration board or the 2D parameters.

    • The area containing circles on the calibration board is fully captured.

    • The circles on the calibration board are clearly visible.

    • The point cloud information of the calibration board is complete.

  3. Click More Functions  Advanced Options  Camera Intrinsic Tool in the toolbar to open the camera intrinsic tool.

Check Intrinsics

Monocular Camera

  1. Click Capture Image.

  2. Click Check Internal Parameters.

  3. Confirm the check result. If the internal parameter check result is not qualified, please refer to Correct Internal Parameters.

    Internal Parameter Check Passed

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    Internal Parameter Check Failed

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Stereoscopic Camera

  1. Click Capture Image.

  2. Click Check Internal Parameters.

  3. Confirm the check result. If the internal parameter check result is not qualified, please refer to Correct Internal Parameters.

    Internal Parameter Check Passed

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    Internal Parameter Check Failed

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Calibrate Intrinsics

  1. Confirm calibration board model

    • Automatic recognition: Click Capture and Identify Calibration Boardto obtain the calibration board model.

    • Manual selection: Choose the calibration board model from the dropdown menu.

  2. Click Add image，Capture the first image.

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  1. Move the calibration board and click Add Image to capture the second image.

    When moving the calibration plate, it is recommended to translate and rotate the calibration plate at the same time. The recommended positions are the center and four sides of the field of view.

    operations internal parameters callbration pose

  2. Repeat the above steps to capture at least 4 images.

    Unqualified images are marked in red. Click X to delete an image.

  3. Click Calibrate Intrinsics and wait for the calibration to complete.

    • If the calibration is successful, please recheck the intrinsics.

    • If the calibration fails, please try to capture more images or recapturing the images.

Restore Factory Intrinsics

If multiple calibration attempts fail, you can click Restore Factory Intrinsics at the top right corner of the interface to reset the camera intrinsics to their factory settings.