陳銘憲Chen, Ming-Syan臺灣大學:資訊網路與多媒體研究所潘雅嵐Pan, Ya-LanYa-LanPan2010-05-052018-07-052010-05-052018-07-052008U0001-3007200823362900http://ntur.lib.ntu.edu.tw//handle/246246/180645隨著行動電話的普及，二維條碼在手機上的應用在最近幾年已經引起很大關注。之前相關的研究都是假設條碼是印在平坦的表面上，然而，這樣是不夠的，我們發現，如果條碼是印在非平坦表面，例如瓶罐上，則上述的假設會使得辨認出條碼的正確率驟減，因此，我們提出了一個有效率且正確的演算法，從扭曲過的二維條碼照片上擷取並把扭曲的二維條碼繳正回來。另外，我們也提出cell-to-cell的概念來提高辨識條碼的效率。和之前相關的演算法比較，我們的方法在條碼的辨識上有比較高的正確率及效率。With the ubiquity of cellular phones, mobile applications with 2D barcodes have drawn a lot of attentions in recent years. All previous works assume that barcodes are printed on flat surfaces. However, we find out that the above assumption does not hold and indicate that the barcodes on distorted surfaces tend to deteriorate the accuracy of recognition. Therefore, we propose an effcient and effective algorithm to rectify and extract 2D barcoden a distorted image. Compared with previous approaches, our algorithm is of high quality with higher accuracy of the barcode recognition.1 Introduction 1 QR code Overview 3.1 Two Dimensional Barcode . . . . . . . . . . . . . 3.1.1 QR-code Advantages . .. . . . . . . . . . . . . 5.1.2 QR code Structure . . . . . . . . . . . . . . . 7.1.3 Applications . . . . . . . .. . . . . . . . . . 9 Related Works 10 Heuristic Algorithm 12.1 Binary Process . . . . . . . . . . . . . . . . . .12.1.1 Changing Color Space . . . . .. . . . . . . . . 12.1.2 Binarization . . . . . . . . . . . . . . . . . 12.2 QR code Detection . . . . . . . . . . . . . . . . 15.2.1 Finding Three Finder Patterns and Corners . . . 15.2.2 Calculate Module . . . . .. . . . . . . . . . . 18.3 Model Curve Boundary . . . . . . . . . . . . . . 21.4 Cell-to-Cell Mapping . . . . . . . . . . . . . . 24.5 RQR on 2D Distortion Image . .. . . . . . . . . . 24 Experimental Results 30.1 Effective Analysis . .. . . . . . . . . . . . . . 30.1.1 3D Distorted Images . . . . . . . . . . . . . . 31.1.2 2D Distorted Images . . . . . . . . . . . . . . 32.1.3 Distorted Limitation . . . . . . . . . . . . . 33.2 Efficiency Analysis . . . . . . . . . . . . . . . 33 Conclusion and Future Works 35ibliography. . . . . . . . . . . . . . . . . . . . .36application/pdf3892379 bytesapplication/pdfen-USQR code影像處理圖形辨識行動電話不均勻背景image processingimage recognitionmobile phonenon-uniform backgroundthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/180645/1/ntu-97-R95944033-1.pdf