CAJ | 학술논문

该文实现了3种常见的阈值算法在闪电通道识别中的应用。针对某些闪电通道图像对比度较低的特点，首先对原始图像去除背景光照不均的影响并进行图像增强，再根据所处理的闪电通道图像的具体情况，选择全局自适应阈值法、局部自适应阈值法或基于 Otsu 自适应阈值的 Canny 算子对增强后的图像进行边缘检测，进而对闪电通道进行识别。对所提取到的闪电通道进行形态学和细化处理，最终提取到由连续的像素点序列表示的闪电通道。针对数字图像中闪电通道背景的不同特点，文中提到的3种阈值方法能够有针对性地对不同图像进行通道检测，在保证准确获得清晰边缘信息的同时，较好地兼顾了对弱边缘信息的提取，有效保证了对闪电通道的识别效果。
해문실현료3충상견적역치산법재섬전통도식별중적응용。침대모사섬전통도도상대비도교저적특점，수선대원시도상거제배경광조불균적영향병진행도상증강，재근거소처리적섬전통도도상적구체정황，선택전국자괄응역치법、국부자괄응역치법혹기우 Otsu 자괄응역치적 Canny 산자대증강후적도상진행변연검측，진이대섬전통도진행식별。대소제취도적섬전통도진행형태학화세화처리，최종제취도유련속적상소점서렬표시적섬전통도。침대수자도상중섬전통도배경적불동특점，문중제도적3충역치방법능구유침대성지대불동도상진행통도검측，재보증준학획득청석변연신식적동시，교호지겸고료대약변연신식적제취，유효보증료대섬전통도적식별효과。
General digital cameras,camcorders as well as the BOYS camera specially developed for the lightning observation,are all important tools for lightning research.They are used to obtain the basic data for un-derstanding geometry features of channels and main development processes of lightning.For a long time, extracting lightning channel coordinates from digital images is based on manual processing methods with the relatively low efficiency.With the development of the photoelectric techniques,more and more ad-vanced optical devices are used in lightning observation,such as high-speed cameras and the Automatic Lightning Processing Feature Observation System (ALPS),and data obtained become much richer.How to automatically process these data and improve the efficiency of data extraction and analysis is an urgent need to be addressed. <br> Considering the complexity of lightning discharges and various characteristics of the lightning channel, only one algorithm is not enough to obtain a satisfying recognition result in all situations.Therefore,3 common threshold methods are applied jointly in the lightning channel recognition.Firstly,the impact of the uneven illumination is eliminated by subtracting the background and the contrast of the image is en-hanced.Secondly,global adaptive threshold method,local adaptive threshold method or adaptive Canny operator method is applied for edge detection.And then,morphological and thinning processes are carried out to get the lightning channel represented by the continuous sequence of pixels.Considering different characteristics of the lightning channel digital image,selecting appropriate algorithm can ensure getting a clear edge information even including weak edges,guaranteeing a good recognition effect finally. <br> Through experiments,it can be concluded that for the lightning channel with simple structure and rel-atively uniform brightness,all algorithms mentioned above can get a good recognition result,among which the global adaptive threshold method is simpler and more efficient.Local adaptive threshold method can calculate the threshold for different images universally.And for the low-contrast images with a smooth background,using adaptive Canny operator method can achieve a satisfactory recognition result.