面向暗室照度计检定低对比度示值图像智能识别技术研究

Research on intelligent recognition technology of low contrast image for illuminometer test in darkroom

针对照度计检定过程中所存在光照强弱与对比度变化的问题,本文提出采用基于Single Shot MultiBox Detector (SSD)目标检测框架的低对比度照度计示值识别技术。首先对比主流目标检测框架检测精度和检测速度,选择兼具精度与速度的SSD目标检测框架;其次设计针对低对比度目标检测的数据增强算法,用以提高SSD目标检测框架对低对比度示值图像识别准确率;最后进行实验与结果分析,设计4组不同照度环境下照度计示值识别实验,识别准确率为99. 6%,SSD目标检测框架识别一张图像平均耗时25. 9 ms。实验证明,该技术在不同光照、对比度环境下对照度计示值图像都有很好的识别效果,其检测速度也能保证照度计检定的在线识别。

To solve the problem about the changes of illumination intensity and contrast in the process of illuminance meter verification,this paper proposes a technology in recognizing the measurement value of illumination in the low-contrast environment based on SSD target detection framework.Firstly,we compare the detection accuracy and detection speed of the mainstream target detection framework,and select the SSD target detection framework whichown both accuracy and speed.Secondly,we design the data enhancement algorithm for the target detection of low-contrast images to improve the recognition accuracy.Finally,an experiment and result analysis were carried out,and the illuminance measurement value recognition experiment in 4 different illumination environments was designed.The recognition accuracy rate was 99.6%,and the average time taken by the SSD target detection frame to deal with a picture was25.9 ms.The experiment proves that the technology has a good recognition effect in detecting images under different illumination and contrast degree environments,and the detection speed can also be used to the online recognition of the illuminance meter verification.