二维条形码阅读器.doc

二维条形码阅读器
N. Normand, C. Viard-Gaudin
{ nnormand,cvg } ***@
Laboratoire Analvse et Traitement des Images (LATVSEI)
IRESTE - Route de Gacheti CP 3003 - 44087 NANTES CEDEX 03; FRANCE
摘要
为了替代激光条码扫描器,我们已经制定了一项基于二维视觉系统的全球性的解决方案。It is composed of two main functions: bar code localization on the overall image, and the reading :条形码的图像定位和读阶段. The localization of the symbol which can be oriented in any direction is carried out with an original method which relies upon the extraction of high density area of mono-oriented . The reading method is based on the detection of the transitions between the stripes by extracting the zero-crossings of the second derivative of the 1D signal reconstructed from the 20 bar code . This system has been tested on several hundred images, the results show a global success rate (localization and decoding) of 100% within a wide range of acquisition parameters, resolution and depth of field, as the camera is not auto-focused the images can be deeply blurred这一系统已经测试了数百影像结果显示,全球的成功率(本地化和解码)100%内广泛采集参数决议和景深,镜头不是自动聚焦的影像模糊,可以深深
条形码阅读器除了激光扫描器外，作为条形码阅读器，我们发明了一种基于二维视图的全球通用的解决方案，主要由两个主要部分组成：一是条码图形的定位，二是阅读解码的步骤。
条形码图形的定位可以在任一的方向上实行，我们只需要用一个原始的方法：我们从一个方向来析取一个高密度区域一个方向上的梯度。阅读解码的方法的选取取决于我们对二维码的开始符号的解析和ID符号的重建。这种方法在全球几百种码制上进行上实验，成功率为100%，由于扫描相机不是自动调焦的，所以图