How to remove background from an image?

Hello,

I'm doing project on object recognition, and in one of my module, i need to extract the feature but for that removal of background is necessary.. so how can i do this?? please help me!

The link for database which i am referring is as mentioned below, http://www.imageprocessingplace.com/downloads_V3/root_downloads/image_databases/MPEG7_CE-Shape-1_Part_B.zip

Thanks!

Answer 1

[Walter Roberson]

In every one of the images in that .zip file, the background has already been removed.

Removal of background is what you do when you have a picture of a real object, or at least a model of that object whose picture has been taken. For example if you had a picture of an apple sitting on a plate, you would need to remove the plate (and the table and everything else that was not the object of interest.)

[Nikhil]

sir here all the images contains only one object!! i just need to remove that black background, so i would like to know, how can i do this??

[Walter Roberson]

What would you like to replace the black background with?

[Image Analyst]

Oh no, here we go all over again!

[Nikhil]

black background with nothing!! i just want to remove that.

[Walter Roberson]

Wait... I think I may finally have it:

C = num2cell(YourImage);
C(~YourImage) = {};

This will give you a cell array in which there are empty cells ("nothing") where the background was, and cells containing [1] where the foreground was.

[Nikhil]

sir it gave me an error 2nd line.

The error is " In an assignment A(:) = B, the number of elements in A and B must be the same."

[Walter Roberson]

C = num2cell(YourImage);
C(~YourImage) = {{}};

[Nikhil]

yes sir it worked but sir how can i make it visible??

[Walter Roberson]

Oh, if you want to make it visible, you use the technique I told you to use before:

imagesc(YourImage, 'AlphaData', YourImage)
colormap(gray)
set(gca, 'color', 'none')

Depending on what you have done before in that session you might need to add

set(gcf, 'renderer', 'opengl')

[Nikhil]

It worked!!

Thanks a ton sir, you helped me through out! Thanks once again!

[Subha]

Sir with this code i implemented to my histopathological image.... now i need to calculate statistical and textural features... how can i process it again.. i have segmented cell as in color cell segmentation in matlab.. now with this code removed the black color... but hw can i proceed with further processing. give ur suggestion sir.. i've tried cell2mat ,, but its not supporting...

[Image Analyst]

Please start your own question. Upload your image , then tell us where it is. You also would need to explain, in that new question, what exactly "further processing" means because that is way too vague to answer.

[muthu selvam]

Sir i doing Pattern recognition Letters Project.. I see the lot math works web page . But i have don't collect How to Remove background from image? I need the coding for remove background from the image..... Advance Thanks...

[Sneha Rauniyar]

sir i am doing dust particle monitoring project for this i have to remove all background expect dust particle from the image... What should i do? Could you suggest me some matlab codes?

[Walter Roberson]

Sneha Rauniyar I recommend you start a new Question, and post a couple of images. You will need to clarify how you know whether a particular dust particle is a foreground dust particle to be kept, or a background dust particle to be removed.