how to draw a diagonal in the given image from the top left corner to the bottom right corner?

i want to draw a diagonal in the given image from the top left corner to the bottom right corner

Answer 1

[Image Analyst]

[rows, columns, numberOfColorChannels] = size(rectangleImage);
x = [1, columns];
y = [1, rows];
line(x,y, 'LineWidth', 4, 'Color', [1, 0, 1]);

Adapt as needed.

[Naishil shah]

I want to remove the top right trianglular portion from the image.How can I do that?

[Image Analyst]

Use poly2mask() to create a binary mask from the 3 triangle vertices. Then blacken the image. I think you may have to do it a color channel at a time

binaryImage = poly2mask(x, y, rows, columns);
% Extract individual color channels.
redChannel = double(rgbImage(:, :, 1));
greenChannel = double(rgbImage(:, :, 2));
blueChannel = double(rgbImage(:, :, 3));
% Now blacken
redChannel(binaryImage) = 0;
greenChannel(binaryImage) = 0;
blueChannel(binaryImage) = 0;
rgbOut = cat(3, redChannel, greenChannel, blueChannel);
imshow(rgbOut);