Generic radial orthogonal moment invariants for invariant image recognition

As the variation of parameters in Jacobi polynomial, Jacobi–Fourier moments can form various types of orthogonal moments: Legendre–Fourier moments, Orthogonal Fourier–Mellin moments, Zernike moments, pseudo-Zernike moments, and so on. In this paper, we present a generic approach based on Jacobi–Fourier moments for scale and rotation invariant analysis of radial orthogonal moments, named Jacobi–Fourier moment invariants (JFMIs). It provides a fundamental mathematical tool for invariant analysis of the radial orthogonal moments since Jacobi–Fourier moments are the generic expressions of radial orthogonal moments. Theoretical and experimental results also show the superiority of the proposed method and its robustness to noise in comparison with some exist methods.     

Tchebichef矩在图像数字水印技术中的应用

提出了一种利用原始图像的Tchebichef矩来增加水印顽健性的方法,即利用原始图像的一个或多个Tchebichef矩的值来估计水印图像所经过的几何变换的参数以及图像增强等图像处理操作的参数,并将这一过程作为水印检测的预处理过程。实验中将多种不同的水印信息在不同的图像处理域(包括DWT、DCT、FFT以及空间域等)实现水印信息的嵌入。为了检测这种估计算法的顽健性,本文实验中的几何攻击是由Stirmark产生的。计算机模拟实验证明这种估计方法简单,估计精度很高,增加了图像水印技术对几何攻击的顽健性,而且可在任何处理域中实现,具有很好的实用价值。1     

Fourier-Mellin矩在图像识别中的应用

为了验证Fourier—Me｜lin矩图像识别中的识别能力,本文研究了其在两种坐标下的计算和重建效果、抗噪性试验。在笛卡尔坐标下,图像重建直接计算,不必转换为极坐标,避免极坐标在了转换时产生的几何和计算误差,试验表明：笛卡尔坐标下,Fourier—Mellin矩的重建比极坐标下更精确,并且OFFM矩对噪声有很好的鲁棒性...     

采用径向Tchebichef矩不变量的飞机型号识别

针对几何矩非正交性对目标描述的不足以及连续正交矩在处理数字图像方面存在离散化误差的缺陷,为了提高识别精度,提出了一种利用离散正交的Tchebichef矩结合全局特征和局部特征的飞机型号识别方法。首先,根据几何矩和Tchebichef矩之间的关系,利用归一化几何中心矩、圆谐函数得到径向Tchebichef矩的旋转、尺度和平移(RST)不变量;然后,利用径向Tchebichef矩提取飞机目标的局部和全局特征构成特征向量;最后,利用Matlab构造了四类飞机的样本集,采用支持向量机(SVM)作为分类器识别测试样本飞机型号,分析了几何矩、Zernike矩和本文方法在识别精度上的差异以及训练样本集大小对识别精度的影响。实验结果表明,本文提出的算法提高了识别精度,并且在训练样本集较小时仍能获得90%以上的识别精度。     

彩色图像中基于Hu矩的手势识别方法研究

手势识别是图像处理中一个主要研究方向,Hu矩由于其良好的不变性被广泛地应用在二值图像中进行图像识别.文中将传统的Hu矩引入到彩色图像中,经过大量的实验,得出了Hu矩在彩色图像中的特性,提出了基于Hu矩的图像旋转识别法,应用在彩色图像的手势识别中.     

Pruned discrete Tchebichef transform for image coding in wireless multimedia sensor networks

After the successful development of the discrete cosine transform (DCT) especially in audio, image and video coding, many state-of-the-arts DCT-based fast algorithms have been developed. However, these algorithms are floating-point and are implemented with high algorithmic complexity and memory intensive. Therefore, they consume large system resources. In particular, those requirements pose a serious limitation on multimedia applications in resource-constrained systems, such as wireless multimedia sensor networks (WMSNs). In this paper we investigate an alternative to DCT transform which known as discrete Tchebichef transform (DTT). Despite its good energy compaction property, low algorithmic complexity and low memory requirements, the DTT is potentially unexploited in the literature. To further reduce its complexity and memory requirements, in this paper we propose a pruned version of DTT (P-DTT). Simulation results show that P-DTT requires a reduced number of arithmetic operations, energy consumption and memory. And it has at the same time competitive compression efficiency compared with Loeffler-DCT and exact DTT. The proposed P-DTT transform is a viable option for image compression and/or communication over WMSNs.