1. Extrinsic and Depth Calibration of TOF-cameras Reporter ：鄒嘉恆 Date ： 2009/12/22

2. Introduction This work presents a calibration procedure that enable user to calibrate the distance- and amplitude-related error of a ToF- camera for a desire operating range.

3. outline Distance-error model  Distance- and amplitude- related errors  Latency-related error  Depth calibration Experimental results Conclusion

4. Distance-error model(1/2) Emits incoherent NIR light : Remitted light : Correlation : Phase delay : Amplitude : Distance :

5. Distance-error model(2/2) P = {v 1, …, v w } represent W image coordinates. v = (r, c) where r and c denote the image row and column Amplitude images : Depth images :

6. Distance- and amplitude-related errors(1/4) Non –ideal NIR-LED response Correlation of the LED- signals with the control signal

7. Distance- and amplitude-related errors(2/4) This phenomenon results in phase-delay- and distance-related error respectively.

8. Distance- and amplitude-related errors(3/4) Distance- and amplitude-related errors are joined and approximated by M penalised splines : Amplitude interval : Spline coefficients : K note points :

9. Distance- and amplitude-related errors(4/4)

10. Latency-related error Different latencies for every pixel have to be taken into account

11. Depth calibration(1/2) Overall error : Corrected distance The distance between an measured point v and the calibration plane in a single shot i

12. Depth calibration(2/2) S includes the spline coefficients, (b 1, b 2 ), (n c, d c ), and t T s

13. Experimental results(1/7) O3D100 ： 50 x 64 pixels Covers a measurement range up 7500mm

14. Experimental results(2/7) Robustness

15. Experimental results(3/7) Precision

16. Experimental results(4/7) Precision Uncalibrated measurements

17. Experimental results(5/7) Precision calibrated measurements

18. Experimental results(6/7) Precision

19. Experimental results(7/7) validity

20. Conclusion The calibration procedure simultaneously estimates the distance parameter and the extrinsic parameters. The calibration procedure considers the distance-related, the amplitude-related and latency-related error.