查询词典 wavelet

On the basis of wavelet transform and S transform,through popularizing basic wavelet, the basic wavelet containing 4 kinds of unknown parameters (amplitude, energy attenuation rate, energy-delay time and apparent frequency ) was constructed, realizing generalized S transform.

在小波变换和S变换基础上，通过对基本小波的推广，构建含有四类待定参数(振幅、能量衰减率、能量延迟时间及视频率)的基本小波，实现广义S变换。

The main theory results includes:(1) Using the properties of Hilbert transform, perfectly reconstruction and new type of lifting scheme, a new type of dual-tree binary coefficients complex wavelet with linear phase is achieved.(2) For linear systems that can be diagonalized by GFT and DST-II matrices, an efficient MGM method is proposed, convergence is proved.(3) We discuss the algebraic structure when Toeplitz matrix is transformed by multi-band wavelet,show that Toeplitz matrix is composed of generating function is transformed to a band and sparse matrix when wavelet applied to this matrix, based on the above results, an efficient solution of Toeplitz equations is obtained, and the computational complex is O,where N is the order of matrix.

理论成果主要包括：(1)对于对偶树二进制系数复数小波，利用Hilbert变换对性质、完全重构条件并结合新的提升格式构造研究了含参系数多进制小波构造方法，作为特例得到具有线性相位的对偶树二进制系数复数小波构造方法；(2)对于广义离散傅立叶变换与正弦变换对角化系统，提出了高效、快速的多重网格算法，理论上证明了算法的收敛性；(3)研究了Toeplitz矩阵在多进制小波变换下的代数结构，验证了多项式生成函数构成的Toeplitz系统在小波变换下的稀疏带宽性质，从而建立基于小波变换求解Toeplitz系统的快速求解方法，运算量级控制在O，其中N为系统的阶。

Experiment results show that binary tree SPIHT suits to true bidimensional wavelet decomposition and it is testified that in true bidimensional wavelet decomposition, the compression effect is comparable between image decomposed by wavelet FB with low order VMs but good interpolating characteristic and that with higher order VMs.

实验证实了二叉树的编码更适合纯二维小波分解，同时也证实了在纯二维小波分解中内插性能好的低阶消失矩的小波滤波器能够产生与高阶消失矩的小波滤波器相同或更好的压缩效果。

By use of bipartition, the entropy of each wavelet block approximates to the target bit rate of one. 5. An efficient algorithm is presented for constructing quantization tables of wavelet blocks with optimal bit allocations for a given image. The algorithm uses wavelet coefficient distribution statistics in a novel way, and pays attention to the traits of HVS.

该算法首先根据每个小波块所含能量的多少和到每个小波块实际编码所用的比特数，给其分配不同的码率；然后根据二分法，通过调整各小波块的量化因子使得各小波块的熵逼近它的目标比特率。

When seismic wavelet is in non-minimum phase , we can make it have smaller phase by doing exponential weighting . As for nonwhite noise problem of reflection coefficient , we may employ logarithmic power spectrum to estimate the autocorrelation function of seismic wavelet , then obtain seismic wavelet and deconvolution opera .

当地震子波为非最小相位时，可利用指数加权方法使之小相位化；对于反射系数非白噪声问题，本文提出利用对数功率谱来估算地震子波的自相关函数进而求取地震子波以及反褶积算子的方法；对于理想的期望子波，本文采用"宽带雷克子波"作为期望输出子波。

The wavelet time-frequency properties of the uncracked rotor and the cracked rotor were discussed by the continuous wavelet time-frequency analysis algorithm. A new algorithm using the wavelet time-frequency analysis algorithm to detect the crack was proposed. The influence of the sampling frequency on the wavelet time-frequency analysis algorithm was analyzed through the numerical simulation research; the valid sampling frequency was presented.

利用连续小波时频分析方法，讨论了裂纹转子与无裂纹转子的小波时频特性，提出了利用小波时频分析方法识别裂纹的新方法；数值仿真研究了采样频率对小波时频分析方法的准确性和有效性的影响，并给出了建议性的采样频率。

We also study on the coding performance of these wavelet. At last, we investigate the wavelet threshold denosing for image, and present a improved Bayes denosing for image. We also combine the wavelet image coding with image denosing based on wavelet threshold, the noising image is compressed, the noise is de-noised at the same time.

最后，在对小波阈值的图像降噪原理进行分析的基础上，提出了一种改进的贝叶斯图像降噪方法，并将小波图像压缩和图像降噪结合在一起，来实现对噪声图像进行压缩的同时对它进行降噪。

To increase the security of the watermark, a new binary image encryption algorithm based on TD-ERCS map is presented. The watermark is encrypted by a chaos sequence generated by TD-ERCS map; A novel color image watermarking algorithm is proposed based on discrete chaotic map and 2-dimensions discrete wavelet transform. The watermark is encrypted by the new binary image encryption algorithm, and the encrypted watermark is embed into four sub-bands of the most deep level of blue branch of host image by three-level wavelet transform, and the embedded positions are determined by general cat cha otic map; A novel color-image blind detection watermarking algorithm is proposed based on integer wavelet transform and subsampling. The scrambled watermark is encrypted and embed into the low sub-bands after four sub-images of the Y branch of host image is transformed by two-level wavelet transform, and the embedded positions are determined by Logistic chaotic map, this watermarking scheme can realize blind extraction.

为了提高水印图像的安全性，提出了一种基于TD-ERCS混沌映射的二值水印图像的加密算法，该算法利用TD-ERCS映射产生的混沌序列加密水印图像；将离散混沌映射和二维离散小波变换相结合，研究了彩色图像水印新算法，该算法先对混沌序列加密后的水印图像进行小波变换，再嵌入到宿主图像的蓝色分量的最深层的四个子带中，嵌入位置则由广义猫映射确定；将整数小波变换和图像子采样技术应用于数字水印，提出了一种彩色图像盲提取水印算法，水印嵌入时，先对宿主图像在YIQ色彩空间中的Y分量进行子采样，并对得到的四个子图像分别进行二级离散小波变换，然后将置乱并加密后的水印图像嵌入到小波变换后的低频子带中，其嵌入位置由Logistic混沌映射产生的混沌序列确定，实现了水印的盲提取。

The application of noise removal for EEG signals based on wavelet transform is discussed in the paper,And the influence on EEG noise removal using different wavelet basis is introduced,Furthermore the wavelet soft-thresholding method and 1-Dimensional wavelet single-branch reconstruction are used for removing noise in EEG.

摘 要 摘要本文探讨了小波变换在脑电去噪中的应用方法，介绍了不同小波基对脑电去噪的影响，比较了小波软门限法和一维小波单支重构去噪方法的去噪效果。

Firstly, the algorithm decomposes the original images with wavelet analysis and obtains the positions of wavelet coefficients that belong to the edges. Then, the algorithm interpolates intensities and positions of those wavelet coefficients between corresponding wavelet sub-images. So that the new image basically satisfies the requirements of medical image interpolation.

通过对原图进行小波变换，获得图像边缘对应小波系数的位置信息，在断层图像的相应小波系数之间进行强度和位置插值，使新的图像不仅在灰度上，而且在组织形状上，介于原来的断层图像之间，满足了医学图像插值的要求。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。