Imwrite() problem with saving sequence images

First, i try to load .mat file into my workspace files = dir('*.mat'); for i = 1:numel(files) load(files(i).name);

Second, i want to read the images in work space and save it as following for k=0:10 output_folder = 'C:\Users\Tossaworn\Desktop'; outputFileName = fullfile(output_folder, ['test' num2str(k) '.tif']);

imwrite(IR0000__,outputFileName); end

IR0000__ is 1 image, but i want IR0001__,IR0002__, ...and output test0,1,2,... . Now output can run, but i have no idea to read the input images. please suggest, Thank you.

Answer 1

[Guillaume]

Here is how I would do it:

 output_folder = 'C:\Users\Tossaworn\Desktop';

 files = dir('*.mat'); 
 for fidx = 1:numel(files)
    matcontent = load(files(fidx).name);  %load into structure
    filenumber = regexp(files(fidx).name, '\d+', 'match', 'once');  %get numeric part of filename
    imagename = sprintf('IR%s__', filenumber);   %build variable name
    assert(isfield(matcontent, imagename), 'mat file %s does not contain image %s', files(fidx).name, imagename);
    outputfilename = fullfile(output_folder, sprintf('test%s.tif', filenumber));
    imwrite(matcontent.(imagename), outputfilename);
  end

[Tossawon Ngamnet]

Oh, many thanks. Its work perfectly.

thank you so much

[Tossawon Ngamnet]

I have written this code to create multiple .tif to be avi video, but something wrong with my code. Could you help me to solve this?

[Guillaume]

Please don't post screenshots of code, it's impossible to copy and paste from a screenshot.

If your tiff images are 16-bit then imread should already return a uint16 array, hence your conversion to uint16 is redundant. To convert a uint16 image to double use im2double, which rescale the intensities to the range 0-1. So

I = imread(filename);
writeVideo(outputVideo, im2double(I));

[Tossawon Ngamnet]

Sorry for my careless. I did the code follow your suggestion. Its work, but the avi file cannot open. Code below:

outputVideo = VideoWriter('newvideo.avi');
outputVideo.FrameRate = 30;
outputVideo.Quality = 100;
open(outputVideo);

srcFiles = dir('C:\Users\Tossaworn\Desktop\testTIFfiles\*.tif');  
for k = 1 : length(srcFiles)
    filename = strcat('C:\Users\Tossaworn\Desktop\testTIFfiles\',srcFiles(k).name);
I = imread(filename);
writeVideo(outputVideo, im2double(I));
end

Is that due to unspecified size?

[Guillaume]

You're missing a

close(outputVideo);

at the end. If that's not the reason for the problem, then I don't know. Try a different video player which may give more insight.