ARToolKit Camera Calibration for Android

From ARToolworks support library

Contents 1 About the application 2 Requirements 3 How do I use it? 4 What information is uploaded when I use this app?

About the application

This application allows you to generate calibration parameters for the lens on your Android device. Good quality lens calibration can be used to improve ARToolKit tracking on your device.

After capture, lens calibration data that meets a certain minimum level of quality is saved on ARToolworks lens calibration data server, and may be shared with other users of the same model of device.

Requirements

• The application requires Android v2.2 or later.
• A printer is required to print the calibration pattern.
• A network connection (e.g. wifi or cellular data) is required to upload the data. Without this, the does not serve any useful purpose.

How do I use it?

Click here to read detailed directions on the calibration procedure for ARToolKit for Desktop.

1. Before beginning, print out the calibration chessboard pattern and affix it to a flat surface. See Calibrating_your_camera#Setting_up.
2. After launching the app, you can use the Settings menu to choose the camera and resolution to be calibrated. To access the Settings menu, press the hardware menu button on the device or use the menu button on the Action Bar at the top of the screen (on Android devices without a hardware menu button).
3. Collect calibration images. See Calibrating_your_camera#Capturing_calibration_images.
4. Once all images have been collected, the calibration data will be calculated, and when this is complete the results will be shown on-screen.
5. The calibration data is automatically uploaded.

What information is uploaded when I use this app?

If a calibration dataset generated with the app meets a certain minimum level of quality is saved at the completion of calibration, and uploaded when a network connection is available. The calibration file itself contains lens optical and distortion parameters (basically an ARParam structure).

As well as the calibration file itself, the following information is transmitted:

• The make and model of device (e.g. Samsung Galaxy S).
• Which camera on the device the parameters apply to.
• The date and time at which the calibration file was generated.
• The calibration data quality (error values).

No personally identifying data is transmitted or stored during as part of the process. Additionally, the data is uploaded via a secure HTTPS connection.