Dateigröße von Bildern per Batch anpassen?

for /f "delims=" %%i in ('dir /b /a-d "D:\Dein Bilderordner\klein\*.jpg"') do if %%~zi gtr 51200 echo Zu verkleinern: %%i (derzeit: %%~zi Bytes)

:: schnipp----- ResizePics.cmd ----
@echo off&setlocal

set "iPath=%ProgramFiles%\IrfanView\i_view32.exe"  

set "CurrentPictPath=E:\Pics\"  

set "CurrentPict=*.jpg"  

:: Darf nicht im Selben Verzeichnis sein wie die Quelle
set "ResizedPath=E:\ResPics\"  


:: Maximale Auflösung einstellen
:: "ResDimMax="    -> Keine Obere Auflösungsgrenze 
:: "ResDimMax=50"  -> Gibt den Wert der Größten möglichen Auflösung an 

set "ResDimMax=800"  

:: Minimale Auflösung einstellen 
:: "ResDimMin=" -> Qualitäts einstellung hat Vorrang 
:: "ResDimMin=0"   -> Qualitäts Einstellung Bleibt 100% 
:: "ResDim=50"  -> Qualität wird ab dieser Auflösung Heruntergesetzt 

set "ResDimMin=800"  


:: Einheit der Dateigröße (B, KB, MB)
set "SizBits=KB"  

:: Maximale Dateigröße einstellen 
set "ResSizMax=50"  

:: Minimale Dateigröße einstellen (in KB)
:: sollte wenigstens 500 bytes kleiner als ResSizMax sein (wird automatisch ausgerechnet wenn gleich)

set "ResSizMin=50"  

:: Minimale mögliche Bildqualität einstellen (Minimal 25 empfohlen)

set "ResQuaMin=30"  



:: Ende Einstellungen
::
set "CurrentPicDat=%Temp%\CPictdat"  
if /i "%SizBits%" == "B"  set /a SizBits = 1  
if /i "%SizBits%" == "KB" set /a SizBits = 1024  
if /i "%SizBits%" == "MB" set /a SizBits = 1048576  

if defined ResSizMax set /a ResSMax = ResSizMax * SizBits
if defined ResSizMin set /a ResSMin = ResSizMin * SizBits
if defined ResSizMin if "%ResSMin%" geq "%ResSMax%" set /a ResSMin - = 500  
for %%i in ("%CurrentPictPath%%CurrentPict%") do echo Bearbeite "%ResizedPath%%%~nxi"&set "CurrentPict=%%~nxi"&set "CurPict=%%~i"& call :dimensons  

pause
goto :eof

:dimensons
set "LongSize=0"  
"%iPath%" "%CurPict%" /info="%CurrentPicDat%"  
if not "%OS%" == "!OS!" setlocal enabledelayedexpansion  
for /f "tokens=4,6" %%j in ('findstr /b /c:"Image dimensions =" "%CurrentPicDat%"') do (  
	for %%l in (%%j %%k) do (
		if !LongSize! lss %%l set "LongSize=%%l"  
)	)
for %%i in ("%CurPict%") do set /a PictSize = %%~zi  
if not defined ResDimOld if not defined ResDimOld (set "ResDimOld=%ResDimMax%") else set "ResDimOld=%LongSize%"  
if not defined ResQua (set "AQuali=100") else set "AQuali=%ResQua%"  
if defined Test goto :SizeMax
:DimMax
if not defined ResDimMax goto :DimMin
if %ResDimMax% leq %LongSize% (set "Resolution=/resize=(%ResDimMax%,%ResDimMax%)"&goto :Quali)  
:DimMin
if not defined ResDimMin goto :Quali
if %ResDimMin% geq %LongSize% (set "Resolution=/resize=(%ResDimMin%,%ResDimMin%)")  
:Quali
if defined ResQua set "Qualit=/jpgq=%ResQua%"  
if not defined Test goto :Picture
:SizeMax
if not defined ResSizMax goto :SizeMin
if %ResSMax% leq %PictSize% goto :Kleiner
if not defined ResSizMin echo %LongSize%x, %AQuali%%%, %PictSize% byte&echo.&endlocal&goto :eof
:SizeMin
if not defined ResSizMin goto :Picture
if %ResSMin% geq %PictSize% goto :groesser
echo %LongSize%x, %AQuali%%%, %PictSize% byte&echo.&endlocal&goto :eof
:Picture
"%iPath%" "%CurrentPictPath%%CurrentPict%" %Qualit% %Resolution% /aspectratio /resample /convert="%ResizedPath%%CurrentPict%"  
if defined Test if not defined ResSizMax (echo %LongSize%x, %AQuali%%%, %PictSize% byte&echo.&endlocal&goto :eof)
set "CurPict=%ResizedPath%%CurrentPict%"  
set "Test=1"&goto :dimensons  
:kleiner
if not defined Test goto :SizeMin
if defined ResDimMax (
	set /a "ResDim= ResDimMax - ( ResDimMax / 20 )"  
) else set /a "ResDim= LongSize - ( LongSize / 20 )"  
if defined ResDimMin (
	if !ResDimMin! leq %ResDim% (
		set "ResDimMax=%ResDim%"  
	) else if not !ResDimMin! == %LongSize% (
		set "ResDimMax=%ResDimMin%"  
	) else (
		if not defined ResQua (
			set "ResQua=95"  
		) else set /a ResQua - = 5
	)
) else (
	if not defined ResQua (
		set "ResQua=95"  
	) else set /a ResQua - = 5
)
if defined ResQua (
	if defined ResQuaMin (
		if !ResQuaMin! leq %ResQua% (set "ResQua=%ResQua%") else echo Quali minimum erreicht&echo %LongSize%x, %AQuali%%%, %PictSize% byte&echo.&goto :eof  
	) else set "ResQua=%ResQua%"  
)
set "Test=" & goto :DimMax  
:groesser
if not defined Test goto :Picture
if defined ResDimMax (
	set /a "ResDim= ResDimMax + ( ResDimMax / 25 )"  
) else set /a "ResDim= LongSize + ( LongSize / 30 )"  

if %ResDimOld% geq %ResDim% (
	set "ResDimMax=%ResDim%"  
	set "LongSize=%ResDim%"  
	set "ResQua="  
) else (if defined ResQua (
		set "ResQua="  
		) else echo Maximum Dimension erreicht&echo %LongSize%x, %AQuali%%%, %PictSize% byte&echo.&goto :eof
	)
)
set "Test=" & goto :DimMax  
:: schnapp----- ResizePics.cmd ----