how to design 3x3 low pass filter in matlab ?

[rahul.achates]

Hi

I am new to MATLAB and just started learning the thing.

how to design 3x3 loww pass filter with custom coefficient ? and how to apply that filter on image ?

 

[rahul.achates]

Some one please reply ... I am interested in learning this stuff .. if anyone have some link to understand this .. please post it here.

It will be great help to me ..

 

[helpmejerry]

What exactly do you mean by 3x3?

BR Jerry

 

[rahul.achates]

below is the question -

Create a 3×3 low-pass filter with all coefficients equal to 1/9, i.e., create a 3×3 MATLAB array with all elements equal to 1/9.

I tried to figure out , but not able to dig much in deep.

 

[sreevenkjan]

if I understand your question clearly...are you saying how to create a filter kernel 3x3 then its very simple.just follow the below Matlab commands which I have written below

matrix = ones(3,3);
weight = 1/9;
filter=matrix.*weight;
output=filter2(filter,input);

here you need to give your input signal.you can also try checking by using different co-efficient values and also by increasing the size of the filter.

 

[rahul.achates]

Thanks sreevenkjan

I will try that code in matlab ..

input ..I have image file which I am reading it MATLAB.

Rahul

 

[sreevenkjan]

Hi Rahul

you need to use a 2D image not a 3D image(color image)...try giving different values and check how the filter affect the image.

Sreeni