發(fā)布時間：2018-05-10 10:24

  本文選題：漢信碼 + 預處理　； 參考：《吉林大學》2014年碩士論文

【摘要】：作為具有自主知識產(chǎn)權的免費二維碼體系，，漢信碼所具有的優(yōu)勢主要體現(xiàn)在其超強的漢字處理能力.有鑒于此，漢信碼在日常實踐中的使用日益廣泛，對漢信碼的研究也逐漸成為熱點.漢信碼在增值稅發(fā)票上取代普通密文用來存儲發(fā)票信息，除票面上的數(shù)字信息外，對貨物名稱、規(guī)格型號、單位都能進行存儲，從而有效的避免了隨意開發(fā)票、偽造發(fā)票等非法行為.目前，利用普通掃描儀采集發(fā)票票面信息，然后應用解碼算法還原漢信碼票面信息的技術已經(jīng)比較完善，2012年后此項技術已經(jīng)逐漸投入使用，其識別率也由最開始的85%提升到了現(xiàn)在的98%. 但是，設備價位、設備噪聲和圖像采集速度等問題嚴重限制了漢信碼技術的應用范圍，影響了漢信碼本身的應用前景.因此，最近市場開始出現(xiàn)用數(shù)碼攝像頭作為拍照方式采集漢信碼圖像的設備，這雖然在一定程度上解決了上述問題，但設備上的部分功能缺失也同時大幅度提高了漢信碼的解碼難度，從而對我們的解碼算法提出了更高的要求.這就需要我們對處理掃描儀圖像的算法進行大規(guī)模的改進，這些改進主要集中在圖像采集、預處理等幾個方面.例如，在圖像采集時遇到的紅色印章過濾、亮度不均勻等問題上，我們就有針對性的采用了圖像拼接技術以及白平衡算法對其進行處理，也得到了較好的效果，幾乎沒有影響到識別算法的識別率. 針對漢信碼識別算法中存在的部分問題，我們重新做了調(diào)整，其中包括發(fā)票碼圖區(qū)域的傾斜角度的求取、畸變校正以及插值函數(shù)的選取等，并且提出了改進方法.具體說來，我們應用隨機Hough變換計算漢信碼的傾斜角度；在插值函數(shù)選取方面通過實驗對比發(fā)現(xiàn)雙三次插值比雙線性插值更加適用于我們采集的漢信碼圖像，不僅提高了精度，而且在時間復雜度方面也未出現(xiàn)明顯的差異；另外，利用二次差分、積分方法我們在碼圖分離方面都取得了很好的效果. 2013年火車票QR碼被破譯的新聞傳出，我們對漢信碼的安全問題同樣表示擔憂，因此在漢信碼信息安全方面值得關注，我們用嵌入數(shù)字水印的方法來實現(xiàn)漢信碼的加密，對編碼信息直接進行加密能夠有效的避免常規(guī)識別軟件的成功解碼，應用Arnold置亂算法對編碼信息加密，其變換次數(shù)具有一定的周期性，所以選擇恰當?shù)淖儞Q次數(shù)對加密的有效性很重要.
[Abstract]:As a free QR code system with independent intellectual property rights, Hanxin Code has the advantages of its strong Chinese character processing ability. In view of this, the application of Han letter code in daily practice is becoming more and more extensive, and the research of Chinese letter code has gradually become a hot spot. Han Xin code replaces ordinary ciphertext on VAT invoices to store invoice information. In addition to the digital information on the face, the names, specifications, models and units of the goods can be stored, thus effectively avoiding the arbitrary invoicing. Illegal acts such as forgery of invoices. At present, the technology of collecting invoice face information by ordinary scanner and applying decoding algorithm to restore ticket face information of Hanshin code has been quite perfect. After 2012, this technology has been gradually put into use. The recognition rate also rose from 85% at the beginning to 98% now. However, the problems of equipment price, equipment noise and image acquisition speed seriously limit the application scope of Hanshin code technology, and affect the application prospect of Hanshin code itself. As a result, recently, the market has begun to use digital cameras as a means of capturing Hanshin images, although to some extent this has solved the above problems. However, the lack of some functions on the equipment also greatly increases the difficulty of decoding the Hanshin code, which puts forward higher requirements for our decoding algorithm. Therefore, we need to improve the algorithm of scanner image processing on a large scale. These improvements mainly focus on image acquisition, preprocessing and other aspects. For example, in the image collection encountered in the red seal filtering, brightness uneven and other problems, we have targeted the use of image stitching technology and white balance algorithm to deal with it, but also got a better effect. There is little effect on the recognition rate of the recognition algorithm. In order to solve some problems existing in the algorithm, we re-adjust it, including the calculation of tilt angle of invoice code area, the correction of distortion and the selection of interpolation function, and the improved method is put forward. In particular, we use the random Hough transform to calculate the skew angle of the Chinese signal code, and in the aspect of the interpolation function selection, we find that the bicubic interpolation is more suitable than the bilinear interpolation for the Chinese signal code images collected by us, which not only improves the precision, but also improves the accuracy of the interpolation function. Moreover, there is no obvious difference in time complexity. In addition, we have achieved good results in code graph separation by using quadratic difference and integral method. The news that QR code of train ticket was deciphered in 2013 came out, so we also expressed concern about the security of Hanshin code, so we should pay attention to the security of Hanshin code information. We use the method of embedding digital watermark to realize the encryption of Hanshin code. The direct encryption of the coded information can effectively avoid the successful decoding of the conventional recognition software. The Arnold scrambling algorithm is used to encrypt the coded information, and its conversion times have a certain periodicity. Therefore, it is very important to choose the appropriate number of transformations for the effectiveness of encryption.
【學位授予單位】：吉林大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TP391.44

【參考文獻】

相關期刊論文 前10條

1 何成平;龔益民;俞亞珍;;漢信碼圖像預處理技術及實現(xiàn)[J];包裝工程;2010年01期

2 紀震,張基宏,蔣一峰;小波域的擴頻數(shù)字圖像水印算法[J];電子與信息學報;2001年08期

3 肖翔;劉曉明;王云柯;;QR碼圖像的矯正與定位方法研究[J];計算機科學;2007年11期

4 何廣華;;增值稅發(fā)票抵扣聯(lián)移動認證系統(tǒng)[J];計算機時代;2010年12期

5 黃文杰;陳斌;;一種快速圖像處理的積分圖方法[J];計算機應用;2005年S1期

6 胡長暉;葉夢君;葉天鳳;萬里光;張先鶴;張佳銳;;數(shù)字攝像頭路徑識別技術的研究與應用[J];可編程控制器與工廠自動化;2012年08期

7 劉云龍;呂韜;曾晉;劉法旺;;基于android手機的加密QR二維碼識別系統(tǒng)[J];軟件;2012年04期

8 周艷瓊,子蔭;增值稅發(fā)票認證識別管理系統(tǒng)[J];四川會計;2000年06期

9 劉彥偉;王根英;劉云;;QR碼信息加密的研究與實現(xiàn)[J];鐵路計算機應用;2012年11期

10 何宇;周志剛;卜智勇;;基于Symbian OS智能手機的二維碼識別系統(tǒng)[J];微計算機信息;2011年06期

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