How to save multiple output images with same file type as the original input image?

I am taking multiple input images, and doing active contour segmentation like this:

[B,L]=bwboundaries(tumor,'noholes'); %draw boundaries around the tumor and no holes needed.
for i=1:length(B)
 rows, columns, numberOfColorChannels] = size(imageArray);
 mask = poly2mask(B{i}(:,2),B{i}(:,1),  rows, columns);
end
B0=mask;
img1=activecontour(imageArray,B0,iteration,'edge');

Now, I want to save img1, which is a biinary image, as the same file extension as the original image. If the original image is in png, I want the mask also to be png.

In am using the following to save output,

path = myFolder;   % mention your path 
myfolder = 'Segmented Pictures' ;   % new folder name 
folder = mkdir([path,filesep,myfolder]) ;
path  = [path,filesep,myfolder] ;

    temp=[path,filesep,baseFileName,'.png'];
    saveas(gca,temp);

But here, I have to select the output image type (here it is .png) and the output is like this, with white borders all around(like the output figure in matlab),

I want to input multiple images and want to save the output images in a selected folder, similar like the code above. The output images should look like this(This is not mask for another image):

How do I do it?

Answer 1

[yanqi liu]

sir，please check the follow code to get some information

for more information,you can read the book 《计算机视觉与深度学习实战》

[~,~,filetype] = fileparts('youfile.jpg')

filetype = '.jpg'

clc; clear all; close all;
im = imread('https://www.mathworks.com/matlabcentral/answers/uploaded_files/723174/image.png');
im = im2bw(im);
figure; imshow(im)

im = imclearborder(im);
figure; imshow(im)