How do I change image background to black?

Hello! Is there a code that substitutes the image background with a black background?

I brought a picture as an example!

Answer 1

[DGM]

For a crude binary masking:

inpict = imread('https://www.mathworks.com/matlabcentral/answers/uploaded_files/938679/image.jpeg');

hsvpict = rgb2hsv(inpict); % convert to hsv
mask = hsvpict(:,:,2) <= 0.25; % look for low-saturation regions
mask = bwareafilt(mask,1); % pick the largest object (the background)

outpict = inpict;
outpict(mask(:,:,[1 1 1])) = 0; % fill background with black

imshow(outpict)

It can be more complicated, but that's a basic approach. If you want to figure out what thresholds to use, you can try to open your image in the Color Thresholder app and explore the options.