msrcr算法matlab代码
时间: 2023-07-28 07:07:27 浏览: 72
以下是 MSRCR 算法的 MATLAB 代码:
```matlab
function imOut=MSRCR(im,sigmaSpatial,sigmaRange,lambda,offset)
%MSRCR Multi-Scale Retinex with Color Restoration
% imOut=MSRCR(im,sigmaSpatial,sigmaRange,lambda,offset) applies the
% Multi-Scale Retinex with Color Restoration algorithm to the input
% image im, using the specified parameters.
%
% sigmaSpatial: the spatial standard deviation of the Gaussian filter
% used in the algorithm (default = 10).
% sigmaRange: the range standard deviation of the Gaussian filter
% used in the algorithm (default = 0.05).
% lambda: parameter used in the color restoration algorithm
% (default = 0.1).
% offset: offset added to the logarithm in the algorithm
% (default = 1e-10).
%
% Example:
% im=imread('peppers.png');
% imOut=MSRCR(im);
% figure;imshow(im);title('Original Image');
% figure;imshow(imOut);title('Processed Image');
%
% Reference:
% Jobson, D. J., Rahman, Z., & Woodell, G. A. (1997).
% Multiscale Retinex for color image enhancement.
% IEEE Transactions on Image Processing, 6(3), 451-462.
if nargin<2
sigmaSpatial=10;
end
if nargin<3
sigmaRange=0.05;
end
if nargin<4
lambda=0.1;
end
if nargin<5
offset=1e-10;
end
% Convert the image to double
im=im2double(im);
% Apply the MSRCR algorithm
imOut=zeros(size(im));
for i=1:size(im,3)
imOut(:,:,i)=MSRCR_Channel(im(:,:,i),sigmaSpatial,sigmaRange,lambda,offset);
end
end
function imOut=MSRCR_Channel(im,sigmaSpatial,sigmaRange,lambda,offset)
% Apply the MSRCR algorithm to a single channel of the image
% Compute the logarithm of the image
imLog=log(im+offset);
% Compute the Laplacian of the logarithm
imLogLaplacian=imfilter(imLog,fspecial('laplacian'),'symmetric');
% Compute the standard deviation of the Laplacian
sigmaLaplacian=std2(imLogLaplacian);
% Compute the scale space
scaleSpace=zeros(size(im,1),size(im,2),5);
for i=1:5
scaleSpace(:,:,i)=imfilter(imLog,fspecial('gaussian',[i*2+1 i*2+1],sigmaSpatial),'symmetric');
end
% Compute the range filter
rangeFilter=zeros(size(im,1),size(im,2),5);
for i=1:5
rangeFilter(:,:,i)=max(scaleSpace(:,:,1:i),[],3)-min(scaleSpace(:,:,1:i),[],3);
end
rangeFilter=max(rangeFilter,[],3);
% Compute the range standard deviation
sigmaRangeFilter=std2(rangeFilter);
% Compute the output
imOut=exp(lambda*(imLog-sigmaRange^2./sigmaLaplacian.*(rangeFilter-imLogLaplacian./sigmaLaplacian)))-offset;
% Clip the output to the range [0,1]
imOut=min(max(imOut,0),1);
end
```
使用方法:
使用 `MSRCR` 函数来对图像进行处理。例如,可以使用以下代码来读取图像并使用 MSRCR 算法进行处理:
```matlab
im=imread('peppers.png');
imOut=MSRCR(im);
figure;imshow(im);title('Original Image');
figure;imshow(imOut);title('Processed Image');
```
其中,`peppers.png` 是一个示例图像文件名。