imread file does not exist - Unable to read file with multiple images

I am trying the following code which reads a file containing multiple images -

clc; clear all; 
% Specify the filename containing images
filename = 'D:\BMPtoPNG'
% Read all images from the file
images = imread(filename); ......

But the command prompt shows -

Error using imread

File "D:\BMPtoPNG" does not exist.

Please let me know how to solve this error.

[Walter Roberson]

It would be rare that you have an image file directly underneath the drive letter (instead of in a folder).

It would be rare that your image file would not include a file extension.

It would be more likely that you have something like

filename = 'D:\BMPtoPNG\asg240311.bmp';

[Vishnu Sree Shanthanu]

Thank you for the response.

The Folder name is - BMPtoPNG

Multiple Image files are inside this folder and I want to read the folder.

[DGM]

That's not how imread() works. If you want to read everything in a directory, you have to read each file individually.

https://www.mathworks.com/matlabcentral/answers/364209-how-to-read-all-types-images-from-the-folder-regardless-of-file-extension

https://www.mathworks.com/matlabcentral/answers/62399-how-to-load-multiple-images-and-processing-the

https://www.mathworks.com/matlabcentral/answers/320689-get-path-to-all-files-in-a-folder-of-images

https://www.mathworks.com/matlabcentral/answers/?search_origin=ans_leaf&term=read+images+folder

[Stephen23]

https://www.mathworks.com/help/matlab/ref/matlab.io.datastore.imagedatastore.html

Answer 1

[Walter Roberson]

% Specify the filename containing images
foldername = 'D:\BMPtoPNG';

% Read all images from the file
dinfo = dir(foldername);
dinfo([dinfo.isfolder]) = [];   %get rid of all subfolders including . and ..
filenames = fullfile({dinfo.folder}, {dinfo.name});

nfile = numel(filenames);
images = cell(nfile,1);
for K = 1 : nfile
  this_image = imread(filenames{K});
  images{K} = this_image;
end

%now images is a cell array of image contents

Answer 2

[Image Analyst]

To process a sequence of files in a folder, see code snippets in the FAQ:

https://matlab.fandom.com/wiki/FAQ#How_can_I_process_a_sequence_of_files?