How do I perform string operations on variables in a for loop?

Question

This sounds dumb, but I can\'t get it to work. I think i just dont\' understand the difference between %%v, %v% and %v

Here\'s what I\'m trying to do:

Answer 1

Yet another way that I prefer is to create a sub-routine (:processMpeg) that I call for each element in the For loop, to which I pass the %%v variable.

for %%v in (*.flv) do call :processMpeg "%%v"
goto :eof

:processMpeg
  set fileName=%~n1
  echo P1=%1  fileName=%fileName%  fullpath=%~dpnx1
  ffmpeg.exe -i "%~1" -y -f mjpeg -ss 0.001 -vframes 1 -an "%filename%.jpg"
  goto :eof