Research on Distortion Correction of QR Code Images

The QR code (Quick Response code) is a two-dimensional barcode which can be stored quite complex and large data and be decoded very fast. In this paper, a new distortion correction method is proposed to correct distorted QR code images taken by mobile phones adaptively. Firstly, the QR code image is filtered. Then, the gradient-based Hough Transform (HT) is modified to shorten the processing time and preserve enough information when detecting the contour lines of QR code symbol. An algorithm for acquiring the four vertices of QR code is proposed during the process. At last, the Inverse Perspective Transformation (IPT) and gray level interpolation are performed. Experiments show that this algorithm can achieve satisfactory results under various acquisition situations.