Can't view binary image

Dear all, I couldn't view the binary image after runing this code

    fab_img = imread('fabric.png');
    Img = rgb2gray(fab_img);
    BW1 = edge(Img,'sobel');
    figure (500)  
    fig500 = gcf;
    ax2 = subplot(1,1,1, 'Parent', fig500);
    image(ax2, (BW1));

Any idea how to solve it without using imshow function?

Meshoo

Answer 1

[Image Analyst]

I would use imshow also. But if you insist on using image you can do it if you multiply the logical matrix by 255:

fab_img = imread('fabric.png');
Img = rgb2gray(fab_img);
BW1 = edge(Img,'sobel');
image(255 * BW1);

[Mesho]

Thank you Image Analyst. I want a solution to the 'image' function properties such that it can show a binary image (not by changing my binary image to another a color or gray image).

[Image Analyst]

Sorry we can't help you. We offered solutions and for some baffling reason you rejected all of them. "The idea here is not to use imshow function."

fab_img = imread('fabric.png');
subplot(2, 2, 1);
imshow(fab_img);
Img = rgb2gray(fab_img);
BW1 = edge(Img,'sobel');
% Option 1
subplot(2, 2, 2);
imshow(BW1);
% Option 2
subplot(2, 2, 3);
image(255 * BW1);
% Option 3 leave as binary but must convert to 3-D RGB image
subplot(2, 2, 4);
image(cat(3, BW1, BW1, BW1));

The display is just for your viewing pleasure. It doesn't have anything to do with the analysis of the image. I don't know how the image is displayed is of such great concern to you. Just pick one and go with it.

Answer 2

[Praveen Reddy]

Hi Mustafa,

I understand that you want to display binary image in a figure. You can use "imshow" method to display binary image.Refer to the following modified code.

fab_img = imread('fabric.png');
Img = rgb2gray(fab_img);
BW1 = edge(Img,'sobel');
figure (500)  
fig500 = gcf;
ax2 = subplot(1,1,1, 'Parent', fig500);
imshow(BW1);

To know more about "imshow" method, please refer to the following MATLAB documentation

https://www.mathworks.com/help/matlab/ref/imshow.html

[Mesho]

Thank you Praveen. The idea here is not to use imshow function.

I need to call the figure. The above code works for rgb images but not for binary images and I wonder if there is any way to solve it.