Hey,
I have plotted few lines in an image and I want to extend these lines until the image borders (end).
I tried to call ''aLine'' command and also use some basics trigonometry, but it did not work for all the lines.
Any idea?
Thanks.
MATLAB: Extend line until the image borders.
image processingImage Processing Toolbox
Related Solutions
To plot in different colors you have to specify a linespec in plot, like
d=plot(t,x, 'r-', 'LineWidth', 2); % Plot red line of width 2.
d=plot(t,x, 'b-', 'LineWidth', 3); % Plot blue line of width 3.
d=plot(t,x, '-', 'LineWidth', 2); % Plot line of width 2 in next default color;
Here's a full demo:
numLines = 10lineColors = jet(numLines);x = linspace(0, 2*pi, 1000);period = pi;legendStrings = cell(numLines, 1);for k = 1 : numLines y = sin(2*pi*x/(k * period)); plot(x, y, '-', 'Color', lineColors(k, :), 'LineWidth', 3); hold on; legendStrings{k} = sprintf('Curve #%d', k);endgrid on;xlabel('x', 'FontSize', 20);ylabel('y', 'FontSize', 20);legend(legendStrings, 'Location', 'southwest');Also see attached m-file for a different demo.
It's just 3 lines. Just mask the original image:
binaryImage = grayImage > 150;maskedImage = zeros(size(grayImage)); % Initialize.
maskedImage(binaryImage) = grayImage(binaryImage);See the full demo below:
% Demo by ImageAnalyst
clc; % Clear the command window.
close all; % Close all figures (except those of imtool.)
clear; % Erase all existing variables.
workspace; % Make sure the workspace panel is showing.
fontSize = 14;% Read in a standard MATLAB gray scale demo image.
folder = fullfile(matlabroot, '\toolbox\images\imdemos');baseFileName = 'coins.png';% Get the full filename, with path prepended.
fullFileName = fullfile(folder, baseFileName);% Check if file exists.
if ~exist(fullFileName, 'file') % File doesn't exist -- didn't find it there. Check the search path for it.
fullFileName = baseFileName; % No path this time.
if ~exist(fullFileName, '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; endendgrayImage = imread(fullFileName);% Get the dimensions of the image.
% numberOfColorBands should be = 1.
[rows columns numberOfColorBands] = size(grayImage);% Display the original gray scale image.
subplot(2, 2, 1);imshow(grayImage, []);title('Original Grayscale Image', 'FontSize', fontSize);% Enlarge figure to full screen.
set(gcf, 'units','normalized','outerposition',[0 0 1 1]);% Give a name to the title bar.
set(gcf,'name','Demo by ImageAnalyst','numbertitle','off') % Let's compute and display the histogram.
[pixelCount grayLevels] = imhist(grayImage);subplot(2, 2, 2); bar(pixelCount);grid on;title('Histogram of original image', 'FontSize', fontSize);xlim([0 grayLevels(end)]); % Scale x axis manually.
yl = ylim();line([150 150], [0 yl(2)], 'Color', 'r');% Threshold at 150
binaryImage = grayImage > 150;% Display the original gray scale image.subplot(2, 2, 3);imshow(binaryImage, []);title('Binary Image', 'FontSize', fontSize);% Mask the image
maskedImage = zeros(size(grayImage)); % Initialize.% Assign values from grayImage that are > 150.
maskedImage(binaryImage) = grayImage(binaryImage);% Display the original gray scale image.subplot(2, 2, 4);imshow(maskedImage, []);title('Masked Image', 'FontSize', fontSize);
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