Automatic Iterative Varible Naming

I am working with a lot of images and my workflow has been designed to load up single images, manipulate the image, and write the image back out to a .jpg file. Unfortunatly I recently realised that .jpg is not a loss-less format and I am currently trying to write my image files to .mat variables.

The image write command was useful since I could append text to the file names. Example: load image1.jpg, cropp image1, save as croppedimage1.jpg.

I would like to restore this functionality to my code usings variable names. It may look something like this....

A = [ 1 2 3 4 5 6 7 8 9 10];
for i = 1:10
    B = A(i);
    C = B*2;
    save (i)C   % where the variable name would be 1C.mat, 2C.mat etc.
end

I am not sure if this even the right approach.

Thanks for any suggestions.

Answer 1

[Fangjun Jiang]

FileName=num2str(i,'C%d.mat')

[Aaron]

I am still missing some functionality. Maybe I am not using the save command correctly. Here is what I did

i = 1;

C = 2;

FileName = num2str(i,'C%d.mat) % This produces FileName = C1.mat

then I save

Save C FileName

This produces the variable filename.mat instead of C1.mat. I was hoping to produce C1.mat, C2.mat, C3.mat etc in my directory.

Any other suggestions would be greatly appreciated.

Thanks!

[Fangjun Jiang]

use the function format, save(FileName)

[Aaron]

Fangjun,Thanks! Works like a Champ.

Answer 2

[Walter Roberson]

.jpg is a lossless format if you specify 'Mode', 'lossless' when you do the imwrite(). However, the JPEG lossless format is not as efficient as some of the other lossless formats around.

[Aaron]

Thanks! I went back and looked at the imwrite Help and sure enough there is the lossless command.

I am working on my thesis but I am not much of a programmer.I am just a dirt and rock engineer with an image problem.

Would using the .mat files be more effecient than the .jpg? What other formats would you recomend.

Thanks,

Aaron

[Image Analyst]

Possibly but no other program, such as Photoshop, or even the operating system to produce thumbnail images, will be able to read them. I'd save them as PNG if I were you - that seems to be becoming the most widespread format for lossless images. It's what I use. You might have to cast the arrays to uint8 of or uint16 if you use don't use a .mat format though.