batch merge

echo off
setlocal enabledelayedexpansion enableextensions
set EXT=.srt
set LIST=
for %%x in (%2\*%EXT%) do (
    set NAME=%%x
    set NAME=!NAME:%2\=!
    set NAME=!NAME:%EXT%=!
    set LIST=!LIST! --track-name "0:!NAME!" "%%x"
)
set LIST=%LIST:~1%
c:\video\mkvtoolnix\mkvmerge.exe -o "%3" "%1" %LIST%