Remove White border from Image

How do i remove white border from image as my output image when merging images display an output with a white border.

or is there a way to remove white border from images?

Any expert can offer me guidance how to remove white border from images

Thanks.

[LinusL]

i using gcf to save the image but when it display it show a white border

saveas(gcf, 'setCombine/Pokemon#' + count + '.png')

Answer 1

[Simon Chan]

Try function imcrop

[LinusL]

is there a way to automatic crop, since imcrop need specific axis

[Simon Chan]

Now I understand, the accepted answer in this Link may help you.

Answer 2

[Kristin Habersang]

https://de.mathworks.com/matlabcentral/answers/272409-how-to-cut-an-area-of-image

maybe this can help you.

[LinusL]

it does not help me

Answer 3

[Image Analyst]

Try this:

% Demo by Image Analyst, August, 2021.
clc;    % Clear the command window.
close all;  % Close all figures (except those of imtool.)
clearvars;
workspace;  % Make sure the workspace panel is showing.
format long g;
format compact;
fontSize = 16;
fprintf('Beginning to run %s.m ...\n', mfilename);

%-----------------------------------------------------------------------------------------------------------------------------------
% Read in image.
folder = [];
baseFileName = 'image.PNG';
fullFileName = fullfile(folder, baseFileName);
% Check if file exists.
if ~isfile(fullFileName)
	% The file doesn't exist -- didn't find it there in that folder.
	% Check the entire search path (other folders) for the file by stripping off the folder.
	fullFileNameOnSearchPath = baseFileName; % No path this time.
	if ~exist(fullFileNameOnSearchPath, 'file')
		% Still didn't find it.  Alert user.
		errorMessage = sprintf('Error: %s does not exist in the search path folders.', fullFileName);
		uiwait(warndlg(errorMessage));
		return;
	end
	fullFileName = fullFileNameOnSearchPath;
end
rgbImage = imread(fullFileName);
[rows, columns, numberOfColorChannels] = size(rgbImage)
% Display the image.
subplot(2, 2, 1);
imshow(rgbImage, []);
axis('on', 'image');
caption = sprintf('Original Image : "%s"', baseFileName);
title(caption, 'FontSize', fontSize, 'Interpreter', 'None');
drawnow;
hp = impixelinfo(); % Set up status line to see values when you mouse over the image.

% Set up figure properties:
% Enlarge figure to full screen.
hFig1 = gcf;
hFig1.Units = 'Normalized';
hFig1.WindowState = 'maximized';
% Get rid of tool bar and pulldown menus that are along top of figure.
% set(gcf, 'Toolbar', 'none', 'Menu', 'none');
% Give a name to the title bar.
hFig1.Name = 'Demo by Image Analyst';

%--------------------------------------------------------------------------------------------------------
% Threshold the image.
grayImage = rgb2gray(rgbImage);
% Display the image.
subplot(2, 2, 2);
% imhist(grayImage);
imshow(grayImage, []);
axis('on', 'image');
caption = sprintf('Gray Scale Image');
title(caption, 'FontSize', fontSize, 'Interpreter', 'None');
drawnow;
hp = impixelinfo(); % Set up status line to see values when you mouse over the image.

mask = grayImage < 230; % Determined from impixelinfo or histogram.
% Take largest blob only.
mask = bwareafilt(mask, 1);
% Display the image.
subplot(2, 2, 3);
imshow(mask, []);
axis('on', 'image');
caption = sprintf('Mask Image');
title(caption, 'FontSize', fontSize, 'Interpreter', 'None');
drawnow;
hp = impixelinfo(); % Set up status line to see values when you mouse over the image.

% Get bounding box
props = regionprops(mask, 'BoundingBox');
% Crop the image.
croppedImage = imcrop(rgbImage, props.BoundingBox);
% Display the image.
subplot(2, 2, 4);
imshow(croppedImage, []);
axis('on', 'image');
caption = sprintf('Cropped Image ');
title(caption, 'FontSize', fontSize, 'Interpreter', 'None');
drawnow;
hp = impixelinfo(); % Set up status line to see values when you mouse over the image.