摘要
U-系统是一类L2[0,1]上的正交分段多项式函数系,为了将其推广到二维情形,传统的L2[0,1]2上张量积形式的U变换并不具有旋转不变性.本文提出了一类二维旋转不变U变换(Rotation-invariant U transform,RIUT).RIUT将U-系统函数与调和函数相结合,使得图像的旋转转化为相位的平移而模保持不变.与经典的正交旋转不变矩(如Zernike矩)相比,RIUT具有诸多特别的性质,从而在图像特征提取中具有良好的潜力.本文将RIUT应用到二值图像检索中的实验结果表明,RIUT具有更高的检索精度.
U-system is a class of orthogonal piecewise-polynomial function system in L^2[0, 1], and its generalized U- system in L^2[0, 1]^2 with tensor-product form is not rotation-invariant. In this paper, we present a novel 2D transform named rotation-invariant U transform （RIUT）. The construction of RIUT combines U-system functions with harmonic functions so that the object/s rotation is transformed into its phasets translation and the modulus keeps unchanged. Compared with the classical rotation-invariant moments, such as Zernike moment, RIUT has many special properties, suggesting an applying potential in image feature extraction. The experiment results for binary image retrieval show that RIUT method has a higher retrieval precision.
出处
《自动化学报》
EI
CSCD
北大核心
2016年第9期1380-1388,共9页
Acta Automatica Sinica
基金
国家自然科学基金(61602213
61170320
61402201)
浙江大学CAD&CG国家重点实验室开放课题(A1609)
中央高校基本科研业务费专项资金(JUSRP11416)
国家科技支撑计划(2015BAH54F00)资助~~
