@echo off
setlocal enabledelayedexpansion

set ext=avi
set bit_rate=133K

set dir_vid_scr=C:\Users\yura\Downloads\Video\



set file1=video1
set file2=video2
set file3=video3
set file4=video4
set file5=video5
set file6=video6
set file7=video7
set file8=video8
set file9=video9
set file10=video01
set file11=video11
set file12=video12
set file13=video13
set file14=video14
set file15=video15
set file16=video16
set file17=video17
set file18=video18
set file19=video19
set file20=video20
set file21=video21
set file22=video22
set file23=video23
set file24=video24
set file25=video25
set file26=video26
set file27=video27
set file28=video28
set file29=video29
set file30=video30
set file31=video31
set file32=video32
set file33=video33
set file34=video34
set file35=video35
set file36=video36
set file37=video37
set file38=video38
set file39=video39
set file40=video40

cd "%dir_vid_scr%"



if /i exist "%file1%.%ext%" (goto :recompress_file1) else (
echo "%file1%.%ext%" NOT EXISTS!
goto :if_after_file1_exists )

:if_after_file1_exists
if /i exist "%file2%.%ext%" (goto :recompress_file2) else (
echo "%file2%.%ext%" NOT EXISTS!
goto :if_after_file2_exists )

:if_after_file2_exists
if /i exist "%file3%.%ext%" (goto :recompress_file3) else (
echo "%file3%.%ext%" NOT EXISTS!
goto :if_after_file3_exists )

:if_after_file3_exists
if /i exist "%file4%.%ext%" (goto :recompress_file4) else (
echo "%file4%.%ext%" NOT EXISTS!
goto :if_after_file4_exists )

:if_after_file4_exists
if /i exist "%file5%.%ext%" (goto :recompress_file5) else (
echo "%file5%.%ext%" NOT EXISTS!
goto :if_after_file5_exists )

:if_after_file5_exists
if /i exist "%file6%.%ext%" (goto :recompress_file6) else (
echo "%file6%.%ext%" NOT EXISTS!
goto :if_after_file6_exists )

:if_after_file6_exists
if /i exist "%file7%.%ext%" (goto :recompress_file7) else (
echo "%file7%.%ext%" NOT EXISTS!
goto :if_after_file7_exists )

:if_after_file7_exists
if /i exist "%file8%.%ext%" (goto :recompress_file8) else (
echo "%file8%.%ext%" NOT EXISTS!

и т.д до 40
........................
.........................
.........................

:if_after_file37_exists
if /i exist "%file38%.%ext%" (goto :recompress_file38) else (
echo "%file38%.%ext%" NOT EXISTS!
goto :if_after_file38_exists )

:if_after_file38_exists
if /i exist "%file39%.%ext%" (goto :recompress_file39) else (
echo "%file39%.%ext%" NOT EXISTS!
goto :if_after_file39_exists )

:if_after_file39_exists
if /i exist "%file40%.%ext%" (goto :recompress_file40) else (
echo "%file40%.%ext%" NOT EXISTS!
goto :exit )







:recompress_file1
echo Processing file1 '%file1%.%ext%' in folder '%dir_vid_scr%'
echo.
ffmpeg -loglevel error -i %file1%.%ext% -c:v libx264 -c:a copy -b:v %bit_rate% -maxrate %bit_rate% -bufsize %bit_rate% %file1%_rcm.%ext%
echo Checking video duration for '%file1%.%ext%'
echo.

for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file1%.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_orig_file1=%%i
for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file1%_rcm.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_rcm_file1=%%i

echo original file duration: %dur_orig_file1% sec.
echo recompressed file duration: %dur_rcm_file1% sec.
if %dur_orig_file1% == %dur_rcm_file1% (
echo GREAT. files have same duration. Will remove original video '%file1%.%ext%'
del "%file1%.%ext%"
echo removed ok.
)
echo ----------------------------------------------------------------
echo.
goto :if_after_file1_exists

:recompress_file2
echo Processing file2 '%file2%.%ext%' in folder '%dir_vid_scr%'
echo.
ffmpeg -loglevel error -i %file2%.%ext% -c:v libx264 -c:a copy -b:v %bit_rate% -maxrate %bit_rate% -bufsize %bit_rate% %file2%_rcm.%ext%
echo Checking video duration for '%file2%.%ext%'
echo.

for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file2%.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_orig_file2=%%i
for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file2%_rcm.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_rcm_file2=%%i

echo original file duration: %dur_orig_file2% sec.
echo recompressed file duration: %dur_rcm_file2% sec.
if %dur_orig_file2% == %dur_rcm_file2% (
echo GREAT. files have same duration. Will remove original video '%file2%.%ext%'
del "%file2%.%ext%"
echo removed ok.
)
echo ----------------------------------------------------------------
echo.
goto :if_after_file2_exists

:recompress_file3
echo Processing file3 '%file3%.%ext%' in folder '%dir_vid_scr%'
echo.
ffmpeg -loglevel error -i %file3%.%ext% -c:v libx264 -c:a copy -b:v %bit_rate% -maxrate %bit_rate% -bufsize %bit_rate% %file3%_rcm.%ext%
echo Checking video duration for '%file3%.%ext%'
echo.

for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file3%.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_orig_file3=%%i
for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file3%_rcm.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_rcm_file3=%%i

echo original file duration: %dur_orig_file3% sec.
echo recompressed file duration: %dur_rcm_file3% sec.
if %dur_orig_file3% == %dur_rcm_file3% (
echo GREAT. files have same duration. Will remove original video '%file3%.%ext%'
del "%file3%.%ext%"
echo removed ok.
)
echo ----------------------------------------------------------------
echo.
goto :if_after_file3_exists

:recompress_file4
echo Processing file4 '%file4%.%ext%' in folder '%dir_vid_scr%'
echo.
ffmpeg -loglevel error -i %file4%.%ext% -c:v libx264 -c:a copy -b:v %bit_rate% -maxrate %bit_rate% -bufsize %bit_rate% %file4%_rcm.%ext%
echo Checking video duration for '%file4%.%ext%'
echo.

for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file4%.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_orig_file4=%%i
for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file4%_rcm.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_rcm_file4=%%i

echo original file duration: %dur_orig_file4% sec.
echo recompressed file duration: %dur_rcm_file4% sec.
if %dur_orig_file4% == %dur_rcm_file4% (
echo GREAT. files have same duration. Will remove original video '%file4%.%ext%'
del "%file4%.%ext%"
echo removed ok.
)
echo ----------------------------------------------------------------
echo.
goto :if_after_file4_exists

:recompress_file5
echo Processing file5 '%file5%.%ext%' in folder '%dir_vid_scr%'
echo.
ffmpeg -loglevel error -i %file5%.%ext% -c:v libx264 -c:a copy -b:v %bit_rate% -maxrate %bit_rate% -bufsize %bit_rate% %file5%_rcm.%ext%
echo Checking video duration for '%file5%.%ext%'
echo.

for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file5%.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_orig_file5=%%i
for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file5%_rcm.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_rcm_file5=%%i

echo original file duration: %dur_orig_file5% sec.
echo recompressed file duration: %dur_rcm_file5% sec.
if %dur_orig_file5% == %dur_rcm_file5% (
echo GREAT. files have same duration. Will remove original video '%file5%.%ext%'
del "%file5%.%ext%"
echo removed ok.
)
echo ----------------------------------------------------------------
echo.
goto :if_after_file5_exists




и т.д до 40

--------------------------
-----------------------------
-----------------------------




:recompress_file39
echo Processing file39 '%file39%.%ext%' in folder '%dir_vid_scr%'
echo.
ffmpeg -loglevel error -i %file39%.%ext% -c:v libx264 -c:a copy -b:v %bit_rate% -maxrate %bit_rate% -bufsize %bit_rate% %file39%_rcm.%ext%
echo Checking video duration for '%file39%.%ext%'
echo.

for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file39%.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_orig_file39=%%i
for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file39%_rcm.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_rcm_file39=%%i

echo original file duration: %dur_orig_file39% sec.
echo recompressed file duration: %dur_rcm_file39% sec.
if %dur_orig_file39% == %dur_rcm_file39% (
echo GREAT. files have same duration. Will remove original video '%file39%.%ext%'
del "%file39%.%ext%"
echo removed ok.
)
echo ----------------------------------------------------------------
echo.
goto :if_after_file39_exists

:recompress_file40
echo Processing file40 '%file40%.%ext%' in folder '%dir_vid_scr%'
echo.
ffmpeg -loglevel error -i %file40%.%ext% -c:v libx264 -c:a copy -b:v %bit_rate% -maxrate %bit_rate% -bufsize %bit_rate% %file40%_rcm.%ext%
echo Checking video duration for '%file40%.%ext%'
echo.

for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file40%.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_orig_file40=%%i
for /f %%i in ('"ffprobe.exe -v error -show_entries format=duration %file40%_rcm.%ext% -of default=noprint_wrappers=1:nokey=1"') do set dur_rcm_file40=%%i

echo original file duration: %dur_orig_file40% sec.
echo recompressed file duration: %dur_rcm_file40% sec.
if %dur_orig_file40% == %dur_rcm_file40% (
echo GREAT. files have same duration. Will remove original video '%file40%.%ext%'
del "%file40%.%ext%"
echo removed ok.
)
echo ----------------------------------------------------------------
echo.
goto :exit







:exit
echo PLEASE GOOD BYE!

Укажите свой путь и свой список файлов

451P_895K_63403191.avi
fk_653_242k_46547292.avi
bolshaya-igra-2017.flv
voyna-2017.flv