how to remove the background from an image ?

i want to remove the background from the image so i can get the grapes only ... but i don't know how to... pls help :) .. i attached the image..... thanks in advance :)

Answer 1

[Image Analyst]

Very easy. Just use the Color Thresholder on the Apps tab.

1. Load the Color Thresholderapp
2. Load the image
3. choose hsv color space.
4. Adjust thresholds for green
5. Click the Export Function button.

See attached m-file

If you want, you can use find() or regionprops() to find the bounding box of the mask and crop the image to the bounding box.

Answer 2

[yanqi liu]

clc; clear all; close all;
im = imread('https://www.mathworks.com/matlabcentral/answers/uploaded_files/785503/image.jpeg');
jm = rgb2lab(im);
vm = mat2gray(jm(:,:,3));
bw = im2bw(vm);
im2 = im;
im2(~cat(3,bw,bw,bw)) = 255;
figure; imshow(mat2gray(im2));

Answer 3

[Chunru]

There are many image segmentation techniques availble in image processing toolbox. Search "image segmentation" in documentation. Below is one technique:

RGB = imread("image.jpeg");
imshow(RGB);
L = superpixels(RGB, 500);

% foreground
f = drawrectangle(gca, 'Position', [2000 1000 1500 600], 'Color', 'g');
foreground = createMask(f, RGB);

% background
b = drawrectangle(gca, 'Position', [10 10 4500 600], 'Color', 'r');

background = createMask(b, RGB);

% Segmentation
BW = lazysnapping(RGB, L, foreground, background);

RGBseg = RGB;
RGBseg(repmat(~BW, [1 1 3])) = 0;

figure
imshow(RGBseg)