Image processing with Matlab : Popular Command & Instruction

 Basic image processing functions:  

• Read an Image : imread() 

The 'imread()' command will read an image into a matrix:

example : img = imread(abc.jpg); 

• Size of an Image :  size() 

example:    size(img) 

It's a 340x650 matrix with 3 RGB channels. 

• Display an image: imshow()

To show our image, we will use imshow() command.

example : imshow(img) 

• Export an Image : imwrite()

imwrite(img,'s.png','png'); 

• Clear the 'command window' in MATLAB? : clc 

We can clear our MATLAB's 'command window' by using this command

• imaqhwinfo()

This will return the information about all the adaptors available on the system.

 

• vid = videoinput ('winvideo',1);
• preview (vid)

Suppose you want to preview your webcam then type

• vid=videoinput('winvideo',1);
• I=getsnapshot(vid);
• save data

Take photos from your webcam 

• vid=videoinput('winvideo',1);
• for i=1:10 

         I=getsnapshot(vid);
         Fname=['Image',num2str(i),'.jpg'];
         imwrite (I,Fname,'jpg');
         pause(1);
     end

Take 10 photos from the webcam and rename them in your formate

• Create a function in Matlab 

function [ output_args ] = functionName( input_args )
imshow(input_args);
end

• Automatic alignment of code lines in editor, do EDIT->Select ALL, then TEXT -> Smart INDENT

• Create Own Photo (Binary)

col=256;

row=256;

img=zeros(row,col);

img(100:100,:)=1.5;

img(:,100:100)=1.5;

imshow(img);

• Crop an Image 

a=imread('abc.jpg');

i=imcrop(a);

imshow(i)

• rotate an image in Matlab and Subplot

a= imread ('abc.jpg');

i = imrotate(a,180,'bilinear');

i2 = imrotate(a,45,'nearest');

subplot(2,1,1)

imshow(i)

subplot(2,1,2)

imshow(i2)