论文标题
基于最大的Correntropy Criterion和可变中心的最大椭圆形拟合
Robust Ellipse Fitting Based on Maximum Correntropy Criterion With Variable Center
论文作者
论文摘要
离群值的存在会大大降低椭圆拟合方法的性能。我们开发了一种椭圆拟合方法,该方法基于使用可变中心(MCC-VC)的最大Correntropy Criterion对离群值进行鲁棒,其中使用了Laplacian内核。对于单个椭圆拟合,我们制定一个非凸优化问题,以估算内核带宽和中心,并将其分为两个子问题,每个子问题估计一个参数。我们在每个子问题上设计了足够精确的凸近似值,以便获得计算有效的封闭式解决方案。以另一种方式解决两个子问题,直到达到收敛为止。我们还调查了椭圆结合的耦合。尽管存在多种可用于耦合椭圆拟合的椭圆拟合方法,但我们通过利用特殊结构来开发几个椭圆拟合方法。在数据点和椭圆之间的关联不明,我们引入了每个数据点的关联向量,并制定了一个非凸混合构成优化问题,以估计数据关联,该数据关联通过将其放松到二阶锥体程序中大致解决。使用估计的数据关联,我们扩展了提出的方法以实现最终的耦合椭圆拟合。在模拟数据和真实图像中,所提出的方法比现有方法具有更好的性能。
The presence of outliers can significantly degrade the performance of ellipse fitting methods. We develop an ellipse fitting method that is robust to outliers based on the maximum correntropy criterion with variable center (MCC-VC), where a Laplacian kernel is used. For single ellipse fitting, we formulate a non-convex optimization problem to estimate the kernel bandwidth and center and divide it into two subproblems, each estimating one parameter. We design sufficiently accurate convex approximation to each subproblem such that computationally efficient closed-form solutions are obtained. The two subproblems are solved in an alternate manner until convergence is reached. We also investigate coupled ellipses fitting. While there exist multiple ellipses fitting methods that can be used for coupled ellipses fitting, we develop a couple ellipses fitting method by exploiting the special structure. Having unknown association between data points and ellipses, we introduce an association vector for each data point and formulate a non-convex mixed-integer optimization problem to estimate the data associations, which is approximately solved by relaxing it into a second-order cone program. Using the estimated data associations, we extend the proposed method to achieve the final coupled ellipses fitting. The proposed method is shown to have significantly better performance over the existing methods in both simulated data and real images.