1. State Key Laboratory of Precision Measurement Technology and Instrument, Tianjin University,Tianjin 300072, China
2. National Institute of Metrology, Beijing, 100029, China
3. Henan Institute of Metrology, Zhengzhou, Henan 450000, China
Abstract：In order to improve the digital recognition efficiency and precision of caliper display, a digital caliper image recognition algorithm based on improved threading method is proposed. The traditional threading method in the digital image recognition of the digital image with vertical tilt has poor practicality and defects frequently, it cannot be widely promoted in the intelligent manufacturing site. To solve this problem, Radon transform is first used to estimate the vertical inclination a angle of digital image, and then the slant line of the estimated angle is used to replace the traditional vertical line of the threading method, so as to realize efficient recognition through digital image segmentation and processing. Experimental results show that the recognition rate of this algorithm is 98%, which can meet the requirements of high density digital image recognition in industrial measurement.
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2019, Vol. 40 
