A Robust Circular TwoDimensional Barcode and Decoding Method With the popularity of twodimensional (2D) barcodes, many image correction algorithms for twodimensional barcodes have been proposed. However, limited by the form of matrix barcodes, the effectiveness of these correction algorithms is limited. Besides, circular 2D barcodes such as ShotCode have better ability to resist image distortion. But, due to the small information capacity, the research on circular 2D barcodes in recent years is limited. Therefore, we propose a robust circular 2D barcode in this paper. By adopting colourcoding and a new decoding method, it can not only achieve the basic information capacity, but also effectively enhance the ability to resist image distortion. In addition, we propose two indicators (maximum distortion ratio and maximum support opening angle) to measure the image distortion of twodimensional barcodes on geometric bodies. Experiments verify the superiority of the new circular twodimensional barcode and its decoding method.

Realtime Multi Barcode Reader for Industrial Applications The advances in automated production processes have resulted in the need for detecting, reading and decoding 2D datamatrix barcodes at very high speeds. This requires the correct combination of high speed optical devices that are capable of capturing high quality images and computer vision algorithms that can read and decode the barcodes accurately. Such barcode readers should also be capable of resolving fundamental imaging challenges arising from blurred barcode edges, reflections from possible polyethylene wrapping, poor andor nonuniform illumination, fluctuations of focus, rotation and scale changes. Addressing the above challenges in this paper we propose the design and implementation of a high speed multibarcode reader and provide test results from an industrial trial. To authors knowledge such a comprehensive system has not been proposed and fully investigated in existing literature. To reduce the reflections on the images caused due to polyethylene wrapping used in typical packaging, polarising filters have been used. The images captured using the optical system above will still include imperfections and variations due to scale, rotation, illumination etc. We use a number of novel image enhancement algorithms optimised for use with 2D datamatrix barcodes for image deblurring, contrast point and selfshadow removal using an affine transform based approach and nonuniform illumination correction. The enhanced images are subsequently used for barcode detection and recognition. We provide experimental results from a factory trial of using the multibarcode reader and evaluate the performance of each optical unit and computer vision algorithm used. The results indicate an overall accuracy of 99.6 % in barcode recognition at typical speeds of industrial conveyor systems.