• 沒有找到結果。

In the end, we conduct a practical test to demonstrate the performance of the proposed system in the real world. As shown in Figure 5.8(a), the system is built on NVIDIA Jetson TX1 board with a Microsoft LifeCam Cinema webcam and a DELL display. The resolution of camera images captured by webcam are 640 × 360 and the resolution of the target image is 400 × 300. The area of the planar target in the real world is 16 × 12 cm2. We use a texture target image and a textureless target image for the test. Due to the lack of ground truth poses, we use appearance distance Ea defined in (2.6) to evaluate the performance. The target images and the results are shown in Figure 5.8(b) and sample images rendered model with poses obtained from the proposed system are shown in Figure 5.7.

In this tests, the pose estimation unit spends 10 seconds to obtain the initial pose while the pose tracker achieves 11 fps for tracking. The proposed system is able to give the accurate and robust result for both texture and textureless target in the real world.

57

(a)

0 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 0.18 0.2

1 7 13 19 25 31 37 43 49 55 61 67 73 79 85 91 97 103 109 115 121 127 133 139 145 151 157 163 169 175 181 187 193 199

Appearance Distance

Number of Frame Ichiro 2Circle Ichiro

2Circle

(b)

Figure 5.8: (a) The picture of the proposed system for the practical tests. (b) The results of the practical tests for the proposed system. We use two planar targets in the tests, which are texture target Ichiro and textureless target 2Circle. The pixel values are normalized to [0, 1] for calculating the appearance distance.

Chapter 6 Conclusion

In this thesis, we propose a robust direct 3D pose estimation algorithm and de-velop D-PET, a direct 3D pose estimation and tracking system for a planar target.

The proposed algorithm is a two-step scheme. First, the pose of the target with respect to a calibrated camera is approximated estimated using a coarse-to-fine scheme. Next, we use a gradient descent search method to further refine and dis-ambiguate the pose. Extensive experimental evaluations show that the proposed algorithm performs favorably against two state-of-the-art feature-based method-s in termmethod-s of accuracy and robumethod-stnemethod-smethod-s. On the other hand, the propomethod-sed D-PET system which is implemented on an embedded GPU consists of a pose estimation unit and a pose tracker. The pose estimation unit is built based on the proposed algorithm and is responsible for finding the initial pose. In order to perform pose tracking, the pose tracker applies a 3-scale search with the proposed pose search pattern. Experimental results verify that the proposed pose estimation unit has similar performance compared to the proposed algorithm and the pose tracker are able to track the pose in severe conditions. The proposed D-PET system achieves the processing speed of 11 fps on an embedded GPU in practical. Our future work includes implementing the specific VLSI hardware to make the system available on wearable devices.

59

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