dimensionality_reduction

说明：  】利用混沌动力学系统中logistic 映射先对水印图像进行置乱预处理以增强其鲁棒性, 在小波域中将原始音频信号按比例分段, 此比例为原始音频信号低频部分与水印信号个数之比, 然后将水印信号加入到音频信号的 低频部分。用StirMark 攻击后的实验结果表明, 该算法对StirMark 的部分攻击具有一定的鲁棒性。(The logistic- map sequences to encrypt the watermark are used. The original audio signal in DWT (Discrete Wavelet Transform) domain is seperated into some pieces determined by the ratio between the length of the low frequency parts and the length of the encrypted watermark. Every bit of the watermark is added into the relevant pieces of the low frequency parts in the DWT domain. Experimental results show that the algorithm is robust against some StirMark attacks.)

说明：  设基带码元传输间隔为0.1秒，FSK调制参数分别设置频率间隔为5Hz和20Hz，相位分别设置为不连续的和连续的两种。试对比观察4元FSK调制输出等效低通信号的功率频谱。(Let the baseband symbol transmission interval is 0.1 seconds, FSK modulation parameters are set the frequency interval of 5Hz and 20Hz, respectively, set to the discontinuous phase and continuous two. Observation of test 4 yuan FSK modulation output equivalent low pass signal of the power spectrum.)

matlab code for M-code LaTeX Package

how to use a webcam in matlab?

it is nonlinear method for blind source seperation using matlab

Edge detection result should be enhanced using linear method like Median filter to remove the garbage around the pupil to gain clear pupil to determine perfect centre. Get the centre of the pupil by counting the number of black pixels (zero value) of each column and row. Then get each row and column that has the maximum number of these black pixels. Then determine the center by simple calculation according to the image coordinate to set it correct on the image, consequently we can determine the radius of the pupil. Thus we can find the pupillary boundary (inner). A similar procedure is extended by using a coarse scale to locate the outer boundary (limbus) which can be apparent by using the mid-point algorithms of circle and ellipse.

用粒子群思想解决光谱分析问题,对学习光学知识的人很有帮助的，希望对大家有用(Idea of particle swarm to solve the spectrum problem, learning optical knowledge is helpful, and the hope that useful)

利用谱减法进行语音信号的降噪处理，适用于语音增强领域(Using spectral subtraction to reduce the noise of speech signal, it is suitable for the field of speech enhancement)

Audio Stegnography by using LSB Agorithms...

说明：  非线性李雅普诺夫指数计算，PPT，大学教程，可用那个matlab编程计算(The nonlinear LYAPUNOV index)