Research Of The Recognition Algorithms Of DPM Two-Dimensional Barcode Based On Scanner

Direct Part Mark (Direct Part Marking, referred DPM) two-dimensional barcode is a two-dimensional barcode marked on the surface of metal parts which used direct part marking technology. Nowadays DPM two-dimensional barcode is widely used in management and quality tracing.This paper firstly analyzes the structural characteristics of DPM two-dimensional Barcode. Combined with the limited memory and slow running speed of scanner, this paper proposes a recognition algorithm of DPM two-dimensional Barcode which based on scanner. The algorithm includes enhancement of DPM two-dimensional barcode image, binarization, DPM dimensional barcode positioning, distortion correction and decoding. The main contents are as follows:1. On the enhancement of DPM two-dimensional barcode image, taking into account the limitations of scanner’s memory, an improved homomorphic filtering algorithm is proposed to overcome the problem that traditional frequency domain image enhancement algorithms need to occupy a larger memory. Experiments show that this algorithm can effectively remove the highlights and uneven illumination in DPM two-dimensional barcode image.2. On the DPM two-dimensional bar code image thresholding, to avoid the incorrect segmentation, a threshold algorithm which combine OTSU algorithm with Bradly algorithm is proposed. By using this algorithm, the accuracy of the thresholding is improved.3. On the DPM two-dimensional barcode positioning, to avoid the problem that traditional Hough transform algorithm and convex hull algorithm need to occupy a larger memory, a pre-positioning algorithm which based on gradient projection is proposed. And then use scan line algorithm to location the barcode. Experiments show this algorithm can accurately locate the DPM two-dimensional barcode.The DPM two-dimensional barcode recognition algorithm can be compiled into a ELF file through cross-compiler. Then it can be loaded to the two-dimensional barcode scanner. So the DPM two-dimensional barcode can be recognized on scanner.