摘要
牙科X光片在牙科疾病的诊断治疗中越来越重要。牙齿X光片机不像光学相机可以聚焦,常受低对比度和噪声的影响,很难直接借此识别疾病特征,常常需要对图片进行增强处理,故主要探讨一些适用于电子病例的牙科X光图像增强算法。算法主要有直方图均衡化、限制对比度自适应直方图均衡化、锐化中值滤波自适应直方图均衡化和改进的对比度自适应直方图均衡化方法。通过对这些算法处理后的牙科X光片图像的均方根误差(RMSE)、图像信噪比(SNR)和改善对比度指数(CII)以及视觉效果进行比较,发现用改进的对比度自适应直方图均衡化方法处理所得图像的均方根误差、改善对比度指数最小,图像信噪比最大,图像视觉效果清晰。
Dental X-ray photo is more and more important in the diagnosis and treatment of dental diseases.However dental X-ray machine are not like optical camera which can focus.It is often affected by the low contrast and noise and is difficult to indentify the disease characteristics.It needs image enhancement processing.Dental X optical image enhancement algorithm in this paper is mainly about some applicable to the electronic case.This paper discusses the algorithm of histogram equalization and contrast limited adaptive histogram equalization,sharpening,median filtering and adaptive histogram equalization and enhance contrast adaptive histogram equalization method(SMCLAHE). By comparing these algorithms for the dental X-ray image,enhancement effect with root mean square error(RMSE),image signal-to-noise ratio(SNR),improve contrast index(CII)and visual effect comparison are analyzed.It found that SMCLAHE algorithm processing have the smallest RMSE and CII,the largest SNR,and clear view.
引文
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