matlab经典代码大全

哈哈哈

MATLAB

显示正炫余炫图：plot(x,y1,'* r',x,y2,'o b')

定义【0,2π】；t=0:pi/10:2*pi;

定义函数文件：function [返回变量列表]=函数名（输入变量列表）

顺序结构：选择结构

1）if-else-end语句

其格式为：

if 逻辑表达式

程序模块1；

else

程序模块2；

End

图片读取：%选择图片路径

[filename, pathname] = ...

uigetfile({'*.jpg';'*.bmp';'*.gif'},'选择图片');

%合成路径+文件名

str=[pathname,filename];

%为什么pathname和filename要前面出现的位置相反才能运行呢%读取图片

im=imread(str);

%使用图片

axes(handles.axes1);

%显示图片

imshow(im);

边缘检测：

global im

str=get(hObject,'string');

axes (handles.axes1);

switch str

case ' 原图'

imshow(im);

case 'sobel'

BW = edge(rgb2gray(im),'sobel');

imshow(BW);

case 'prewitt'

BW = edge(rgb2gray(im),'prewitt');

imshow(BW);

case 'canny'

BW = edge(rgb2gray(im),'canny');

imshow(BW);Canny算子边缘定位精确性和抗噪声能力效果较好，是一个折中方案

end;

开闭运算：

se=[1,1,1;1,1,1;1,1,1;1,1,1]; %Structuring Element

I=rgb2gray(im);

imshow(I,[]);title('Original Image');

I=double(I);

[im_height,im_width]=size(I);

[se_height,se_width]=size(se);

halfheight=floor(se_height/2);

halfwidth=floor(se_width/2);

[se_origin]=floor((size(se)+1)/2);

image_dilation=padarray(I,se_origin,0,'both'); %Image to be used for dilation

image_erosion=padarray(I,se_origin,256,'both'); %Image to be used for erosion %%%%%%%%%%%%%%%%%%

%%% Dilation %%%

%%%%%%%%%%%%%%%%%%

for k=se_origin(1)+1:im_height+se_origin(1)

for kk=se_origin(2)+1:im_width+se_origin(2)

dilated_image(k-se_origin(1),kk-se_origin(2))=max(max(se+image_dilation(k-se_origin(1):k+halfh eight-1,kk-se_origin(2):kk+halfwidth-1)));

end

end

figure;imshow(dilated_image,[]);title('Image after Dilation'); %%%%%%%%%%%%%%%%%

%%% Erosion %%%

%%%%%%%%%%%%%%%%%

se=se';

for k=se_origin(2)+1:im_height+se_origin(2)

for kk=se_origin(1)+1:im_width+se_origin(1)

eroded_image(k-se_origin(2),kk-se_origin(1))=min(min(image_erosion(k-se_origin(2):k+halfwidth -1,kk-se_origin(1):kk+halfheight-1)-se));

end

end

figure;imshow(eroded_image,[]);title('Image after Erosion'); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%% Opening(Erosion first, then Dilation) %%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

se=se';

image_dilation2=eroded_image; %Image to be used for dilation

for k=se_origin(1)+1:im_height-se_origin(1)

for kk=se_origin(2)+1:im_width-se_origin(2)

opening_image(k-se_origin(1),kk-se_origin(2))=max(max(se+image_dilation2(k-se_origin(1):k+hal fheight-1,kk-se_origin(2):kk+halfwidth-1)));

end

end

figure;imshow(opening_image,[]);title('Opening Image'); %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%%% Closing(Dilation first, then Erosion) %%% %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

se=se';

image_erosion2=dilated_image; %Image to be used for erosion

for k=se_origin(2)+1:im_height-se_origin(2)

for kk=se_origin(1)+1:im_width-se_origin(1)

closing_image(k-se_origin(2),kk-se_origin(1))=min(min(image_erosion2(k-se_origin(2):k+halfwidt h-1,kk-se_origin(1):kk+halfheight-1)-se));

end

end

figure;imshow(closing_image,[]);title('Closing Image');

Warning: Image is too big to fit on screen; displaying at 31% scale.

> In truesize>Resize1 at 308

In truesize at 44

In imshow at 161

图像的直方图归一化：

I=imread(‘red.bmp’);%读入图像

figure;%打开新窗口

[M,N]=size(I);%计算图像大小

[counts,x]=imhist(I,32);%计算有32个小区间的灰度直方图

counts=counts/M/N;%计算归一化灰度直方图各区间的值

stem(x,counts);%绘制归一化直方图

图像平移：

I=imread('shuichi.jpg');

se=translate(strel(1),[180 190]);

B=imdilate(I,se);

figure;subplot(1,2,1),subimage(I);title('原图像');

subplot(1,2,2),subimage(B);title('平移后图像');

图像的转置；

A=imread('nir.bmp');

tform=maketform('affine',[0 1 0;1 0 0;0 0 1]);

B=imtransform(A,tform,'nearest');