The Research And Implemention Of Correction Algorithm For Distorted QR Code

Along with the rapid development of modern information science and technology, as an automated information acquisition technology, the application of QR code is more and more widespread. Among the many barcode, although the one dimensional barcode technology is more mature, more widely used, but one dimensional barcode has the disadvantage of limited storage information, poor security and so on. These shortcomings make the one-dimensional barcode cannot not meet the needs of social development, so the two-dimensional barcode technology to emerge as the times require. Two dimensional bar code has been developed with the times the need, just as its name suggests, is based on one-dimensional bar code adds another dimension readable barcode information is obtained, greatly improve the information capacity of barcode, which also makes barcode represent more information. Among the many two dimensional bar code, due to the large amount of stored information, high fault tolerance, can be expressed in characters and a variety of image text information, confidentiality strong in security, QR code is the most widely used and most far-reaching, In some aspects has changed our way of life.As an important part of two-dimensional barcode technology, two-dimensional barcode recognition mainly using image recognition technology, firstly, using image acquisition equipment to get the image containing two dimensional bar code,then after image processing and data processing to identify two-dimensional barcode, finally extract the text information which is contained in the two-dimensional bar code. According to the phenomenon that the two dimensional bar code is printed in the light of the uneven and the distortion of the goods, this paper proposes a method of correcting the distortion of the QR code.According to the process of image processing algorithm, the two-dimensional barcode is corrected after image preprocessing. On the image threshold segmentation, this paper selects six different method of image threshold segmentation, and through the experimental comparison, we can discover, the global threshold segmentation algorithm by using the image as a whole using the same threshold of segmentation, inadequate lighting part of the loss of useful information, although the local threshold segmentation does not have the phenomenon of losing useful information, but there are a lot of artifacts in the processing results, which seriously affect the follow-up operations, Therefore, an improved algorithm is proposed which is based on threshold segmentation. In order to make quality of image better, this paper presents a method to filter the noise in two-dimensional bar code.In the positioning of QR code, this paper proposes a localization algorithm based on the minimum rectangle, and compared it with the commonly used method for the feature location of the position detection pattern,selects an algorithm with strong robustness. After obtain two-dimensional barcode region, we propose to u se the diagonal of the box to approximate the corner and the position of the QR code to detect the corners of the image are calculated by mapping relationship to derive the corrected image, and propose to establish sampling grid, further provided the positive mass. Experiments show that the distortion of the two-dimensional code correction algorithm can improve the Identification rate of two-dimensional bar code.