二值及多值符合格雷碼法則之結構光線圖應用在非接觸之主動式三維物面掃描

Binary and M-ary Structured Light Patterns with Gray Coding Rule in Active Non-contact 3D Surface Scanning

葉宇欽(Yu-Chin Yeh)

指導教授 ： 鄭文凱

共同指導教授 ： 石勝文

國立暨南國際大學/科技學院/通訊工程研究所/碩士(2009年)

摘要

三維物面掃描系統在現今被普遍地應用在各方面專業領域中，其中Gray code、Hilbert curve是比較常被運用在拍攝上的編碼。本論文在遵守Gray Coding Rule下搭配Hilbert curve的頻率分散特點，將現有Gray code編碼法進行改良與研究。
Gray code有bit變換頻率集中在同一列的問題，高頻率下容易產生投影的影像強度互相干擾，造成解碼時量化錯誤。本文試著編出bit變換頻率平均分散於各列且遵守Gray Coding Rule的編碼，從實驗數據可以證明在這些條件下的編碼方式都可以提升編碼效能。
另外，本文也發現利用互補碼可以幫助解決在level數為2的情況下，高頻率所產生的影響，但付出的代價就是必須增加拍攝張數(資源)，由實驗數據可以證實有明顯的效能提升。

關鍵字

三維掃描系統 ； 互補碼

並列摘要

Nowadays the 3D scanning technique has become a significant focus in computer vision and has professional applications in various fields. In the technology, Gray code and Hilbert curves are the majors codes conventionally used. One of the rows of Gray code, however, exists high frequncy terms due to the fast change of bit values, which causes the interference between the different intensities of the light patterns projected on the scanned project and hence decoding errors happen. In this study, codes with low or no high frequency terms, i.e., the changes of bit values disperse equally in each row, and codes observing Gray Coding Rule, are examined. Moreover, the mutual complement code is also found to possess the capability to solve the problem of the interference caused by the high frequency terms, at the higher cost of the photographic resources.
Finally, the experiment results show that higher accuracy of the 3D scanning has been achieved in the proposed codes, compared with the performance under the conventional Grey code.

並列關鍵字

3D scanner ； Gray Coding Rule ； Mutual complement code

參考文獻

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