How to save different images in sequence ?

hello every one, need your help

i have 144 images in my folder starting from image1 to image144. i want to apply different noise on these images and want to save them in sequence with in the same folder..for example i want to add salt & pepper so how it will be possible to save the noised images in the same folder starting from image 145 to image 288.

image_folder='D:\my work\data';

filenames = dir(fullfile(image_folder,'*.jpg'));

total_images = numel(filenames);

for n = 1:total_images

file=sprintf('%d.jpg', n);

f= fullfile(image_folder, file);

our_images = imread(f);

path= fullfile('D:\my work\traindata',['image', num2str(n),'.jpg']);

imwrite(our_images,path);