如何将信号规范化为零均值和单位方差?

I am new to MATLAB and I am trying to built a voice morphing system using MATLAB.

我是MATLAB的新手，我正在尝试用MATLAB构建一个语音变形系统。

So I would like to know how to normalize a signal to zero mean and unit variance using MATLAB?

所以我想知道如何用MATLAB将一个信号规范化为零均值和单位方差?

5 个解决方案

#1

if your signal is in the matrix X, you make it zero-mean by removing the average:

如果你的信号是在矩阵X中，你把它的平均值去掉:

X=X-mean(X(:));

and unit variance by dividing by the standard deviation:

单位方差除以标准差:

X=X/std(X(:));

#2

If you have the stats toolbox, then you can compute

如果你有stats工具箱，那么你可以计算。

Z = zscore(S);

#3

You can determine the mean of the signal, and just subtract that value from all the entries. That will give you a zero mean result.

你可以确定信号的均值，然后从所有的项中减去那个值。这会给你一个零均值的结果。

To get unit variance, determine the standard deviation of the signal, and divide all entries by that value.

为了得到单位方差，确定信号的标准偏差，并按该值除以所有项。

#4

It seems like you are essentially looking into computing the z-score or standard score of your data, which is calculated through the formula: z = (x-mean(x))/std(x)

看起来你基本上是在计算你的数据的z分数或标准分数，这是通过公式计算出来的:z = (x-均值(x))/std(x)

This should work:

这应该工作:

%% Original data (Normal with mean 1 and standard deviation 2)
x = 1 + 2*randn(100,1);
mean(x)
var(x)
std(x)

%% Normalized data with mean 0 and variance 1
z = (x-mean(x))/std(x);
mean(z)
var(z)
std(z)

#5

To avoid division by zero!

为了避免除法零!

function x = normalize(x, eps)
    % Normalize vector `x` (zero mean, unit variance)

    % default values
    if (~exist('eps', 'var'))
        eps = 1e-6;
    end

    mu = mean(x(:));

    sigma = std(x(:));
    if sigma < eps
        sigma = 1;
    end

    x = (x - mu) / sigma;
end

#1