matlab为图像加模糊

运动模糊

I = imread(‘5.jpg');

>> PSF = fspecial('motion',20,15);

 J = imfilter(I,PSF,'conv','circular');

figure(2),imshow(J);

imwrite(J, ’55.jpg', 'jpg');

'motion'motion filter

为运动模糊算子，有两个参数，表示摄像物体逆时针方向以theta角度运动了len个像素，len的默认值为9，theta的默认值为0；

H = FSPECIAL('motion',LEN,THETA) returns a filter to approximate, once convolved with an image, the linear motion of a camera by LEN pixels,

with an angle of THETA degrees in a counter-clockwise direction. The filter becomes a vector for horizontal and vertical motions.

The default LEN is 9, the default THETA is 0, which corresponds to a horizontal motion of 9 pixels.

散焦模糊

'disk'

circular averaging filter

为圆形区域均值滤波，参数为radius代表区域半径，默认值为5.

H = FSPECIAL('disk',RADIUS) returns a circular averaging filter (pillbox) within the square matrix of side 2*RADIUS+1.

The default RADIUS is 5.

clear

clc

'计算中......'

I=imread('Lena256.bmp');

r=10;%散焦半径r

PSF=fspecial('disk',r);   %得到点扩散函数

I1=imfilter(I,PSF,'symmetric','conv');  %实现散焦模糊

%利用拉普拉斯算子对散焦模糊图像进行二阶微分

I1=double(I1);

h=[1 1 1;1 -8 1;1 1 1];

I2=filter2(h,I1);

%对微分图I2进行自相关计算

R=xcorr2(I2);

R=R/max(R(:));

figure,surfc(R);