Displaying a set of images from a folder

Hello. I need to place a button in my app that displays all the images from a folder one after another with a time delay on a UIAxes and another button that opens a figure. I'm having problems with understanding the process behind opening files via code in matlab. Can anyone help me a bit in this matter?

Answer 1

[Walter Roberson]

projectdir = 'path/to/image/directory';
ext = '.png';  %adjust according to kind of images
dinfo = dir( fullfile( projectdir, "*"+ext) );
fullnames = fullfile({dinfo.folder}, {dinfo.name});
nfiles = length(fullnames);

ax = app.axes1;   %place you want the image to be shown
h = image(ax, []);  %create image object with empty content

for K = 1 : nfiles
   thisfile = fullnames{K};
   [thisimg, thismap] = imread(thisfile);  %handles pseudocolor and rgb both
   h.CData = thisimg;  %update the existing image object with the new image
   if ~isempty(thismap); colormap(ax, thismap); end  %if needed, update colormap
   pause(0.2);
end

The above code does not, however, account for true grayscale images. You would detect those as thismap being empty and ndims(thisimg) is 2 .

[Filip Juchnicki]

Where is ext variable used?

[Walter Roberson]

ext is used in

dinfo = dir( fullfile( projectdir, "*"+ext) );

So for example from .png it would construct the string "*.png" and that becomes the pattern that dir() is to search for -- files with that extension.

Answer 2

[Image Analyst]

FAQ:

https://matlab.fandom.com/wiki/FAQ#How_can_I_process_a_sequence_of_files.3F