How do I make an image name contain another image's name?

I have

 ima1 = 'oranges.png';
ima2 = 'tangerines.png';

but I need to create a new image where the name is 'oranges_vs_tangerines.png'. I am using imwrite, but I don't understand what to put to show the images names. I left it at

   imwrite(nim,'<ima1>_vs_<ima2>.png.')

Then I have to insert the answer into my output

out = 'The RBG values are different: see %s<ima1>_vs_<ima2>.png.'

But I'm writing a function so I can't just put %soranges_vs_tangerines.png. How do I call up the name of the file afterwards? Can I store it in a variable?

Answer 1

[Image Analyst]

Try this:

ima1 = 'oranges.png';
ima2 = 'tangerines.png';
[folder1, baseFileName1, ext1] = fileparts(ima1)
[folder2, baseFileName2, ext2] = fileparts(ima2)
outputBaseFileName = sprintf('%s_vs_%s.png', baseFileName1, baseFileName2)
folder = pwd; % Whatever.....
fullOutputFileName = fullfile(folder, outputBaseFileName);
imwrite(nim, fullOutputFileName)
fprintf('The RGB values are different:\nsee %s\n', fullOutputFileName)

[Danielle]

I did this:

r = im1(:,:,1) == im2(:,:,1);
 g = im1(:,:,2) == im2(:,:,2);
 b = im1(:,:,3) == im2(:,:,3);
 nim = cat(3, r, g, b);
 imshow(nim);
 a = strfind(ima1,'.');
 a = a-1;
 aa = ima1(1:a);
 b = '_vs_';
 c = [aa b ima2];
 imwrite(nim,c); 
 x = 'The RGB values are different: see '; 
 out = [x c];

[Image Analyst]

Do you have any more questions? If not, can you mark it as Accepted?

[Stephen23]

Image Analyst gave some excellent advice, for example:

• using fileparts . Consider what would happen in your code if the filename contained a period character, or no file extension.
• using sprintf to join the filename strings together.
• using fullfile to create a new filename.

You should consider reviewing Image Analyst's code, it really contains some good ideas for your work... and good ways to use MATLAB.

Also note that your code

r = im1(:,:,1) == im2(:,:,1);
g = im1(:,:,2) == im2(:,:,2);
b = im1(:,:,3) == im2(:,:,3);
nim = cat(3, r, g, b);

is simply equivalent to (and could be replaced by):

nim = im1==im2;

Answer 2

[Stephen23]

This is the core code that you need:

>> ima1 = 'oranges.png';
>> ima2 = 'tangerines.png';
>> [~,nam1] = fileparts(ima1);
>> [~,nam2] = fileparts(ima2);
>> ima3 = sprintf('%s_vs_%s.png',nam1,nam2)
ima3 =
oranges_vs_tangerines.png