近幾年來QR Code 早已被廣泛運用在各式各樣便利生活的行為上。QR Code，是Quick Response Code 的縮寫，為一種具有超高速識讀特性的矩陣二維符號，QR -Code 比一維條碼可以儲存更多資料。QR -Code 搭配手機內的照相機，使用解碼軟體，對著QR - Code拍照，解碼軟體會自動讀取QR -code 內含資訊，顯示於手機螢幕上面。但在環境或是人為因素的干擾下所造成QR -Code 失真就會無法順利解碼。由於環境或是人為因素的干擾，通道編碼為必要的技術，其中渦輪碼已被廣泛的使用並證實擁有非常好的效能。渦輪碼的使用能有效的降低系統位元錯誤率。
因此我們提出使用渦輪碼(turbo code) 加入標準QR code，並且使用穿刺(puncturing)，使得編碼長度能與QR code 配合。而且在不破壞QR code 的標準架構下，使用渦輪碼加強的QR code 依然能夠使用標準QR code 解碼器。使用渦輪碼加強解碼器，即使條碼影像有雜訊干擾，還是能夠正確判讀QR code 條碼內的資訊在現有技術中對雜訊和標識嵌入內置的解決措施為QR 碼標準中指定的里德-所羅門（RS）編碼的。但是，光靠RS 編碼是不夠強大。因此，QR 圖像雜訊和/或標誌損壞通常有很高解碼失敗率。本文提出了一種方案，其中提出嵌入QR 碼渦輪代碼（TCS）。使用原來的QR 資料位作為系統位元（TC systematic) 送入碼率為12 的渦輪編碼器，生成查核位元（TC-parity）的。在每個QR 模塊允許四（而不是兩個）不同的灰度級，每個模塊可以攜帶兩個位元: 一個TC-系統位元，而另一個為TC-查核位元。本論文所提出的QR 編碼方案是與標準的QR 解碼兼容的，MSB 位元平面是原始的QR 碼，因此可以直接送入任何標準2的QR 解碼器進行解碼。實驗結果顯示，提出的方案是有效的，在這個意義上，許多傳統解碼失敗的QR code 經由我們的提出的解碼機制有很高的比例能成功解碼。

In recent years, QR codes have found a wide range of applications in business and industry. Moreover, their popularity and function are still growing (fast). In this work, we try to improve the success rate in QR decoding when the QRcode image (also referred to as QR image, for short) is corrupted by noise and/or an embedded logo. In the existing techniques found in the industry and in the literature, the counter-measure against noise and logo embedding is the built-in Reed-Solomon (RS) coding as specified in the QR code standard. The RS codes, however, is not powerful enough.
Therefore, QR images corrupted by noise and/or logos usually suffer a high rate of decoding failure. In this work, a scheme is proposed wherein turbo codes (TCs) are incorporated into QR codes. Using the original QR data bits as the systematic bits (referred to as TCsystematic bits) fed into a rate- 1 2 turbo enoder, parity bits (referred to as TC-parity bits) are generated.
By allowing four (instead of two) different gray levels at each QR module, each module can carry two bits – one (more precisely speaking, the MSB (most-significant bit)) for a TC-systematic bit, and the other (more precisely speaking, the LSB (least-significant bit)) for a TCparity bit. The proposed QR encoding scheme is compatible with the standard QR decoding, in the sense that the MSB bit-plane is the original QR code and thus can be directly fed into any standard QR decoder for decoding. Experiments show that the proposed scheme is effective, in the sense that many failed QR decodings become successful after the processing by our scheme.

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