For loop recursively through folder in windows cmd for file rename

Question

I'm trying to iterate through folders with images to create thumbnails using ImageMagic, and rename thumbnail files with small_ prefix.

when I execute this in single folder, it works great:

FOR %a in (*.jpg) DO convert %a -thumbnail 30% small_%a

To loop through subfolders, I just need /R flag:

FOR /R %a in (*.jpg) DO convert %a -thumbnail 30% small_%a

This will result into new name for thumbnail small_c:\images\image.jpg which is wrong :)

How can I get small_ prefix into file name while recursing through subfolders in script, i.e. from c:\images\image.jpg to c:\images\small_image.jpg ?

Thanks.

Solution

I think this is may suit your case.

for /R %i in (*.jpg) DO convert %i -thumbnail 30% %~di%~pi%~ni_small%~xi

Comments

[Andrija]

I'll just use small_ in front of file name: for /R %i in (*.jpg) DO convert %i -thumbnail 30% %~di%~pismall_%~ni%~xi

[Peter Perháč]

this would not work for me no matter what, until i found in the manual ss64.com/nt/for.html that the correct syntax is double-%, e.g.: for /R %%i in (*.jpg) DO convert %%i...

[naitsirhc]

The double-% is only necessary if running the command in a batch file. If running the for loop at the command prompt, only a single % is required.