一种改进的Canny边缘检测算法

An improved Canny edge detection algorithm

针对Canny边缘检测算法存在的缺陷,提出了一种改进型Canny边缘检测算法。首先采用非线性扩散滤波减少了图像噪声,同时保持图像的边缘信息;在邻域梯度幅值计算中,考虑像素对角线方向的梯度,进一步抑制了噪声的影响;最后采用平均方差阈值法选取阈值,从而提高了对不同图像的自适应性。通过对实验图像的分析表明,该改进算法对含噪图像的边缘提取具有较好的检测精度和准确性。

Aiming at the defects of the Canny eage detection algorithm, an improved Canny edge detection algorithm was presented to obtain thin and robust edge. Firstly, nonlinear diffusion filter was used to wipe of noise efficiently and kept the edge information of the image. Secondly, gradient calculation of pixel diagonal direction was considered in the calculation of neighborhood gradient amplitude which further repressed the impact of noise. Thirdly, using average interelass variance, the self-adaptively double thresholds for different images were calculated. The results of the experiment indicate that the improved algorithm has a better accuracy and precision in the edge detection.