<EXT> for "-c" option

.jpg vs .JPG

Hi,
Great utility ! I like very much that this little exe file can do a lot of things 😊

My need: Do I have the possibility to use something like <EXT> for -c option?
My purpose: Make some resizings and keep exactly the same file names because they will be used on a Linux machine and I have to use correct extension (ex.: .jpg, .JPG )

LaterEdit:
Another option would be to make -z CaseSensitive, and then I would have the possibility to divide my job in 2 parts: for *.JPG and for *.jpg

Thank you,
Best Regards