针对密度峰值聚类算法(clustering by fast search and find of density peaks,DPC)聚类无特定形状的实际数据集时聚类精度欠佳的问题,提出一种最优化密度估计的密度峰聚值类算法。使用最优Oracle逼近(Oracle approximating shrinkage,...针对密度峰值聚类算法(clustering by fast search and find of density peaks,DPC)聚类无特定形状的实际数据集时聚类精度欠佳的问题,提出一种最优化密度估计的密度峰聚值类算法。使用最优Oracle逼近(Oracle approximating shrinkage,AS)计算出最优协方差矩阵,利用最优协方差矩阵构造马氏距离,通过最优协方差矩阵提高DPC对数据相似度的区分能力,在此基础上结合K近邻算法,实现数据样本密度最优估计,利用最优密度估计提高DPC对实际数据集的聚类精度。在人工数据集和UCI真实数据集上进行仿真实验,实验结果表明,改进DPC算法的思路是可行的。展开更多
针对传统的工件图像识别算法运行速度慢、匹配精度差等问题,提出一种改进的ORB(Oriented FAST and Rotated BRIEF)算法解决工件图像的实时与准确识别问题。该算法的流程是首先利用ORB算法提取工件图像的角点特征,随后为其添加SURF(Speed...针对传统的工件图像识别算法运行速度慢、匹配精度差等问题,提出一种改进的ORB(Oriented FAST and Rotated BRIEF)算法解决工件图像的实时与准确识别问题。该算法的流程是首先利用ORB算法提取工件图像的角点特征,随后为其添加SURF(Speed-Up Robust Features)描述符进行方向分配,得到具有旋转尺度不变性的图像角点,结合快速近似最近邻搜索算法进行特征点的匹配,实现工件图像的识别。实验结果表明:在图像存在旋转尺度变化的情况下,使用改进的ORB算法相比传统的ORB、SIFT(Scale Invariant Feature Transform)和SURF算法以及SIFT+SURF、SURF+FREAK组合算法在工件图像角点提取与目标匹配方面速度更快,识别精度更高,提高了工业机器人在搬运工件过程中对工件图像的识别效率和准确性。展开更多
针对核环境下自主式导航机器人对目标识别与跟踪过程中提高特征点匹配的准确率和稳定性问题,提出一种基于加速鲁棒特征(speed up robust features,SURF)算法进行特征提取和特征描述,利用快速最近邻逼近搜索函数库(fast library for appr...针对核环境下自主式导航机器人对目标识别与跟踪过程中提高特征点匹配的准确率和稳定性问题,提出一种基于加速鲁棒特征(speed up robust features,SURF)算法进行特征提取和特征描述,利用快速最近邻逼近搜索函数库(fast library for approximate nearest neighbors,FLANN)算法进行特征点预匹配,并使用随机采样一致性(random sample consensus,RANSAC)算法优化匹配结果,从而实现图像实时匹配与识别。实验结果表明,在不同实验条件下,包括角度变换、缩放变换、局部遮挡、局部光照等,本文算法均能匹配出目标区域内模板图像,具有较好的精确性和稳定性。展开更多
Image matching refers to the process of matching two or more images obtained at different time,different sensors or different conditions through a large number of feature points in the image.At present,image matching ...Image matching refers to the process of matching two or more images obtained at different time,different sensors or different conditions through a large number of feature points in the image.At present,image matching is widely used in target recognition and tracking,indoor positioning and navigation.Local features missing,however,often occurs in color images taken in dark light,making the extracted feature points greatly reduced in number,so as to affect image matching and even fail the target recognition.An unsharp masking(USM)based denoising model is established and a local adaptive enhancement algorithm is proposed to achieve feature point compensation by strengthening local features of the dark image in order to increase amount of image information effectively.Fast library for approximate nearest neighbors(FLANN)and random sample consensus(RANSAC)are image matching algorithms.Experimental results show that the number of effective feature points obtained by the proposed algorithm from images in dark light environment is increased,and the accuracy of image matching can be improved obviously.展开更多
文摘针对密度峰值聚类算法(clustering by fast search and find of density peaks,DPC)聚类无特定形状的实际数据集时聚类精度欠佳的问题,提出一种最优化密度估计的密度峰聚值类算法。使用最优Oracle逼近(Oracle approximating shrinkage,AS)计算出最优协方差矩阵,利用最优协方差矩阵构造马氏距离,通过最优协方差矩阵提高DPC对数据相似度的区分能力,在此基础上结合K近邻算法,实现数据样本密度最优估计,利用最优密度估计提高DPC对实际数据集的聚类精度。在人工数据集和UCI真实数据集上进行仿真实验,实验结果表明,改进DPC算法的思路是可行的。
文摘针对传统的工件图像识别算法运行速度慢、匹配精度差等问题,提出一种改进的ORB(Oriented FAST and Rotated BRIEF)算法解决工件图像的实时与准确识别问题。该算法的流程是首先利用ORB算法提取工件图像的角点特征,随后为其添加SURF(Speed-Up Robust Features)描述符进行方向分配,得到具有旋转尺度不变性的图像角点,结合快速近似最近邻搜索算法进行特征点的匹配,实现工件图像的识别。实验结果表明:在图像存在旋转尺度变化的情况下,使用改进的ORB算法相比传统的ORB、SIFT(Scale Invariant Feature Transform)和SURF算法以及SIFT+SURF、SURF+FREAK组合算法在工件图像角点提取与目标匹配方面速度更快,识别精度更高,提高了工业机器人在搬运工件过程中对工件图像的识别效率和准确性。
基金Supported by the National Natural Science Foundation of China(No.61771186)the Heilongjiang Provincial Natural Science Foundation of China(No.YQ2020F012)the University Nursing Program for Young Scholars with Creative Talents in Heilongjiang Province(No.UNPYSCT-2017125).
文摘Image matching refers to the process of matching two or more images obtained at different time,different sensors or different conditions through a large number of feature points in the image.At present,image matching is widely used in target recognition and tracking,indoor positioning and navigation.Local features missing,however,often occurs in color images taken in dark light,making the extracted feature points greatly reduced in number,so as to affect image matching and even fail the target recognition.An unsharp masking(USM)based denoising model is established and a local adaptive enhancement algorithm is proposed to achieve feature point compensation by strengthening local features of the dark image in order to increase amount of image information effectively.Fast library for approximate nearest neighbors(FLANN)and random sample consensus(RANSAC)are image matching algorithms.Experimental results show that the number of effective feature points obtained by the proposed algorithm from images in dark light environment is increased,and the accuracy of image matching can be improved obviously.
