为了解决仿射最小二乘匹配方法在未知初始参数条件下无法自适应选择匹配窗口的问题,提出了一种基于局部形状估计的自适应窗口最小二乘匹配方法。利用LOG(Laplacian of Gaussian)算子检测特征点以及特征点所在的尺度;在特征点邻域内根据...为了解决仿射最小二乘匹配方法在未知初始参数条件下无法自适应选择匹配窗口的问题,提出了一种基于局部形状估计的自适应窗口最小二乘匹配方法。利用LOG(Laplacian of Gaussian)算子检测特征点以及特征点所在的尺度;在特征点邻域内根据特征尺度计算局部二阶矩矩阵,用二阶矩矩阵估计特征点局部的形状特征;根据特征点局部的形状自适应选择初始匹配窗口进行仿射最小二乘迭代。实验结果表明,该方法在较大仿射变形下能够准确的选择有效匹配区域,避免因窗口内容差异造成的迭代不收敛问题。展开更多
文中基于理论分析,提出了一种宽频带高精度功率检测方法。通过使用测试仪器进行简单的测量,建立实际电路中各工作频率待测功率值与检测电压值之间的计算关系,克服电路器件的参数随频率变化的问题,进而提高对宽带功率信号的检测精度。实...文中基于理论分析,提出了一种宽频带高精度功率检测方法。通过使用测试仪器进行简单的测量,建立实际电路中各工作频率待测功率值与检测电压值之间的计算关系,克服电路器件的参数随频率变化的问题,进而提高对宽带功率信号的检测精度。实测结果表明,对于40~56 d Bm电平值范围的功放输出信号,检测值与实测值误差〈0.8 d B。展开更多
针对医学图像配准对鲁棒性强、准确性高和速度快的要求,本文提出一种基于Rényi熵的互补尺度空间关键点配准算法。该算法首先从图像上提取Harris-Laplace(HL)和Laplacian of Gaussian(LoG)两种互补的尺度空间关键点,然后将关键点对...针对医学图像配准对鲁棒性强、准确性高和速度快的要求,本文提出一种基于Rényi熵的互补尺度空间关键点配准算法。该算法首先从图像上提取Harris-Laplace(HL)和Laplacian of Gaussian(LoG)两种互补的尺度空间关键点,然后将关键点对应的灰度信息融入到联合Rényi熵中,最后使用最小生成树来估计联合Rényi熵。新算法结合了互补关键点的鲁棒性,和最小生成树估计Rényi熵的高效性。实验结果表明在图像含有噪声、灰度不均匀和初始误配范围较大的情况下,该算法在达到良好配准精度的同时,具有较强的鲁棒性和较快的速度。展开更多
Nowadays, computer vision as an interdisciplinary field is growing in different areas such as medical, electronics, etc. In the field, detection and particularly image segmentation is an essential task in which is dif...Nowadays, computer vision as an interdisciplinary field is growing in different areas such as medical, electronics, etc. In the field, detection and particularly image segmentation is an essential task in which is difficult to find the appropriate one based on the application. In this paper, a new algorithm is proposed to segment the lesion from background. The algorithm is based on log edge detector with iterative median filtering. We have tested our algorithm on 20 dermoscopic images and compare the lesion detection results with those manually segmented by dermatologists. The experiments represent the effectiveness of proposed algorithm.展开更多
文摘为了解决仿射最小二乘匹配方法在未知初始参数条件下无法自适应选择匹配窗口的问题,提出了一种基于局部形状估计的自适应窗口最小二乘匹配方法。利用LOG(Laplacian of Gaussian)算子检测特征点以及特征点所在的尺度;在特征点邻域内根据特征尺度计算局部二阶矩矩阵,用二阶矩矩阵估计特征点局部的形状特征;根据特征点局部的形状自适应选择初始匹配窗口进行仿射最小二乘迭代。实验结果表明,该方法在较大仿射变形下能够准确的选择有效匹配区域,避免因窗口内容差异造成的迭代不收敛问题。
文摘文中基于理论分析,提出了一种宽频带高精度功率检测方法。通过使用测试仪器进行简单的测量,建立实际电路中各工作频率待测功率值与检测电压值之间的计算关系,克服电路器件的参数随频率变化的问题,进而提高对宽带功率信号的检测精度。实测结果表明,对于40~56 d Bm电平值范围的功放输出信号,检测值与实测值误差〈0.8 d B。
文摘针对医学图像配准对鲁棒性强、准确性高和速度快的要求,本文提出一种基于Rényi熵的互补尺度空间关键点配准算法。该算法首先从图像上提取Harris-Laplace(HL)和Laplacian of Gaussian(LoG)两种互补的尺度空间关键点,然后将关键点对应的灰度信息融入到联合Rényi熵中,最后使用最小生成树来估计联合Rényi熵。新算法结合了互补关键点的鲁棒性,和最小生成树估计Rényi熵的高效性。实验结果表明在图像含有噪声、灰度不均匀和初始误配范围较大的情况下,该算法在达到良好配准精度的同时,具有较强的鲁棒性和较快的速度。
文摘Nowadays, computer vision as an interdisciplinary field is growing in different areas such as medical, electronics, etc. In the field, detection and particularly image segmentation is an essential task in which is difficult to find the appropriate one based on the application. In this paper, a new algorithm is proposed to segment the lesion from background. The algorithm is based on log edge detector with iterative median filtering. We have tested our algorithm on 20 dermoscopic images and compare the lesion detection results with those manually segmented by dermatologists. The experiments represent the effectiveness of proposed algorithm.
