Digital-watermarking-technology

一个很好的matlab中文帮助文档，希望对学matlab的人有所帮助(A very good Chinese matlab help document, in the hope that people learn matlab help)

说明：  图像处理（验证码识别）程序 内含事例(Image processing (validation code identification) program contains examples of)

HCL Test Paper Pattern (HR Interview, Techincal And Aptitude) Aptitude is an online round. There were only 2 rounds for us. 1.Aptitude(2 Apps for IT and CSE) A. General aptitude(60 que in 50 min) B. Technical Aptitude(Data Structures,C,OS)[25 que in 20 min]

振动分析matlab程序，用于固有频率振型求取。(vibration analysis matalb code)

使用MATLAB，实现以下四个功能 一、获取图片RGB值：给定一张图片，获取点(x,y)，以及(x,y)周围8个点的R、G、B值。 二、实现rgb2gray函数：使用matlab实现rgb2gray的功能，并能计算出转换后灰度图片的方差。 三、灰度图对比度增强：分别使用灰度拉伸和直方图均衡化，增强给定图的对比度。 四、图像去噪：对给定图片加椒盐噪声，并选择两个去噪算法去除椒盐噪声。 (Using MATLAB, to achieve the following four functions First, access to image RGB value: Given a picture, get the point (x, y), and (x, y) around 8 o clock in the R, G, B values. Second, the realization rgb2gray function: using matlab realize rgb2gray functions, and can calculate the variance after the conversion of grayscale image. Third, the grayscale contrast enhancement: namely, the use of gray stretch and histogram equalization, contrast enhancement given graph. Fourth, the image denoising: for a given image add salt and pepper noise, and you know at least two denoising algorithm to remove salt and pepper noise. )

filteirng that can be done where ever possible with compression

约束优化问题： minRosen(Rosen梯度法求解约束多维函数的极值)(算法还有bug) minPF(外点罚函数法解线性等式约束) minGeneralPF(外点罚函数法解一般等式约束) minNF(内点罚函数法) minMixFun(混合罚函数法) minJSMixFun(混合罚函数加速法) minFactor(乘子法) minconPS(坐标轮换法)(算法还有bug) minconSimpSearch(复合形法)(Constrained optimization problem: minRosen (Rosen gradient method for solving constrained multi-dimensional function of extremes) (algorithm also bug) minPF (solving linear equations outside the penalty function method constraints) minGeneralPF (outside the penalty function method for solving general equality constraints) minNF (internal penalty function method) minMixFun (mixed penalty function method) minJSMixFun (mixed penalty function acceleration method) minFactor (multiplier method) minconPS (coordinate rotation method) (algorithm also bug) minconSimpSearch (complex method))

说明：  运动方程中的速度向量和加速度向量用位移的某种组合来表示，将微分方程组的求解问题转化为代数方程组的求解问题，并在时间区间内求得每个微小时间区间的递推公式，进而求得整个时程的反应。 中心差分法是一种显示的积分法，它基于用有限差分代替位移对时间的求导（即速度和加速度）。(Velocity vectors and acceleration vectors in motion equations are expressed by a combination of displacements. The problem of solving differential equations is transformed into the problem of solving algebraic equations. The recurrence formulas of each small time interval are obtained in the time interval, and then the response of the whole time interval is obtained. The central difference method is a display integration method, which is based on the finite difference method instead of the displacement derivative of time (i.e. velocity and acceleration).)

This is the source code about OFDM under the condition of QPSK and perfect compensation.

数字信号处理第九章 IIR滤波器的设计 代码实现(Digital Signal Processing Chapter IX IIR filter design code)