Startconvert.bat and Convert-to-MP4.bat

Startconvert.bat
for %%i IN (*.mpg) DO (convert-to-mp4.bat "%%i")
pause

Convert-to-MP4.bat
IF EXIST "%1.mp4" GOTO exit

@echo Conversion for %1 started on %DATE% %TIME%
ffmpeg -i %1 -c:v libx264 -preset slow -crf 18 -c:a aac -strict experimental -b:a 128k %1.mp4

:exit
@echo %1.mp4 already exists