Reduce padding around saved image

I'm trying to save the contours of an image. I want the contours in my image to be white, on a black background.

grayImage = imread('bench.png');
grayImage = imcomplement(grayImage);
he=imcontour(grayImage, 2, '-w');
set(gca,'XColor', 'none','YColor','none', 'Color','k');
set(gcf, 'InvertHardCopy', 'off');
saveas(gca,'benchcontour.png');

The saved image has extra space around it, which creates issues in what I want to do afterwards.

Original image:

Saved image:

How can I get rid of the padding around the plot?

Answer 1

[Bjorn Gustavsson]

If you save your edge-enhanced image with something like

print -dpng your-image.png

you can increase the fraction of your image to fill the entire figure, something like this:

set(gca,'position',[0 0 1 1])

That should remove the padding.

Another way to go about this is to write the edge-enhanced image to an image directly:

imagesc(img_edge_enhanced)
imwrite(img_edge_enhanced,'your-clean-image.png')

That should produce a BW-image if your img_edge_enhanced is scaled between 0 and 1.

HTH

[Aastha Sharma]

To clarify, what exactly is img_edge_enhanced here? The variable assigned to imcontour?

[Bjorn Gustavsson]

Ah, when you use imcontour, I'd go with the first suggestion. Just add the set(gc,'position',[0 0 1 1]) to your script before your saveas-call. The second suggestion was for the case where you'd made a binary image with some edge-detection-method, such a BW-image you could write directly to an image-file using imwrite. Since you plot an acurla contour-plot of your image you'd be better off using the first option.

HTH