【作者】 王植；

【导师】 贺赛先；

【作者基本信息】 武汉大学 ， 测试计量技术及仪器， 2004， 硕士

【摘要】 边缘检测技术是图像测量、图像分割、图像压缩以及模式识别等图像处理技术的基础，是计算机视觉和图像测量重要的研究课题之一。如何快速、准确的对图像进行边缘检测是图像处理领域的研究热点。 本文首先简要介绍了经典边缘检测算子和一些成熟的边缘检测方法，论述了这些算法的基本原理，比较和分析了它们的优缺点。 本文重点论述了图像处理的多尺度自适应滤波技术。介绍了一种根据局部灰度变化信息，估计边缘尺度的多尺度自适应高斯滤波方法。本文详细论述了多尺度自适应高斯滤波的基本理论和实现方法，并对这种方法进行了有效的改进。 本文提出了一种基于Canny理论，利用多尺度自适应高斯滤波技术的Canny自适应边缘检测方法。Canny自适应边缘检测方法在保持了Canny算子原有的定位准确，单边缘响应和信噪比高等优点的基础上，提高了Canny算子在提取图像边缘细节信息和抑制假边缘方面的性能。Canny自适应边缘检测方法利用图像梯度特征信息自适应的生成动态阈值，提高了边缘检测的自动化程度。本文详细介绍了这种算法的基本思想和具体方法，并通过实验以及对实验结果的分析，证明了Canny自适应边缘检测方法是一种有效的边缘检测方法。 结合论文所述的多尺度自适应高斯滤波方法和Canny自适应边缘检测方法，在实验中实现了对测量图像中标定板的定位、标定点的边缘轮廓和中心坐标的精确定位。通过实验数据和结果，证明了使用本文提出的Canny自适应边缘检测方法可以从不同尺度上快速、准确的检测出目标的边缘轮廓。更多还原

【Abstract】 Edge detection is the base of the image measuring, image segmentation, image compressing and pattern recognition and so on. Edge detection is one of the important subjects in the field of computer vision and image measuring. How to detect the edge of object exactly and quickly is a researchful holspot of image processing.Some classic methods and efficient edge-detection methods are introduced in this paper. The basic concepts of these techniques are summarized and the methods’ advantages and disadvantages are analyzed.Multiscale adaptive filtering is particularly discussed in this paper. Multiscale adaptive Gauss filtering is proposed. This method estimates the scale of edge based on local gray scale statistic. The basic theory and the concrete algorithm of the multiscale adaptive Gauss filtering are summarized and some improvements are made.Based on Canny theory and multiscale adaptive Gauss filtering, an adaptive Canny edge-detection method is proposed in this paper. This method not only keeps the cxcellent performance of Canny operator in good localization, only one response to a single edge and good detection, but also improves the performance in the detail edge-detection and good detection. Canny adaptive method detects the edges with adaptive threshold value according to the gradient information. That improves the automaticity of edge-detection. The theories and the concrete algorithm of the Canny adaptive method are introduced in this paper. With the mathematic analysis and test result, it demonstrates that the Canny adaptive edge-detection method is a valid method on edge-detection.Using the multiscale adaptive Gauss filtering method and the Canny adaptive method, a experiment is designed to orientate the surveyor’s board, extract the exact edges and the center coordinate figures of the surveyor points. With the mathematic analysis and lots of experiments, it demonstrates that using the method proposed in this paper can quickly and exactly detect the edge of object in different scales.更多还原