I have read several posts here on Stackoverflow about binding a variable during a FOR loop. While I figure most of the help provided here has been for Linux/Unix, I'm reaching out for help with batch scripting in Windows. My main goal is to extract the "date created" from a mp4-file and "overlay the date on my video" using ffmpeg (and or ffprobe).
I have experimented a lot, but my latest attempt has been trying to bind the result from ffprobe onto a variable, and use the variable later. My latest and simplest attempt looks like this:
SETLOCAL ENABLEDELAYEDEXPANSION
for %%a in ("*.mp4") do (
for /F "tokens=*" %%G in ('ffprobe -v quiet %%a -print_format compact -show_entries format_tags=creation_time') do (
set DateC=%%G
echo !DateC!)
)
I was hoping to be able to print the tag result from ffprobe using that code, but apparently not. So helping me bind that variable, and how to call it again later inside the following code snippet in Windows, would be deeply appreciated:
ffmpeg -i %%a -filter_complex "drawtext=fontfile=/Windows/Fonts/Arial.ttf:x=28:y=650:fontsize=45:fontcolor=white:box=1:boxcolor=black#0.4:text='!DateC!'" -c:a copy output.mp4
I must also mention I've seen the following code on StackOverflow:
ffmpeg -i %%a -filter_complex "drawtext=fontfile=/Windows/Fonts/Arial.ttf:x=28:y=650:fontsize=45:fontcolor=white:box=1:boxcolor=black#0.4:text='%{metadata\:creation_time}'" -c:a copy output.mp4
But I have the same problem making Windows recognize and print the metadata.
I am certain the file in question contains this metadata.
I suggest this not tested code for the batch file:
#echo off
setlocal EnableExtensions EnableDelayedExpansion
for %%a in ("*.mp4") do (
for /F "delims=" %%G in ('ffprobe.exe -v quiet "%%a" -print_format compact -show_entries format_tags^=creation_time 2^>^&1') do (
set "DateC=%%G"
echo !DateC!
)
)
endlocal
The inner FOR runs in a separate command process started with cmd /C the command line:
ffprobe.exe -v quiet "%%a" -print_format compact -show_entries format_tags=creation_time 2>&1
"%%a" is already replaced by name of current *.mp4 file. The double quotes are necessary in case of current *.mp4 file name contains a space or one of these characters &()[]{}^=;!'+,`~.
It is necessary to escape the equal sign with ^ in arguments list to get the command line correct passed to cmd.exe started by FOR in background.
2>&1 results in redirecting output written to handle STDERR to handle STDOUT because of FOR captures only everything written to STDOUT of the started command process.
The redirection operators > and & must be escaped with caret character ^ on FOR command line to be interpreted as literal characters when Windows command interpreter processes this command line before executing command FOR which executes the embedded ffprobe.exe command line in the separate command process started in background.
I don't have ffprobe.exe and ffmpeg.exe installed, but I think those console applications write information about files to handle STDERR (standard error) instead of STDOUT (standard output) which is the reason for using 2>&1 to get the wanted information captured by FOR and assigned to an environment variable.
"tokens=*" is the same as "delims=". Both result in getting the entire line captured by FOR assigned to loop variable G without splitting it up into substrings (tokens) using space/tab as delimiters, except the line starts with a semicolon in which case FOR would ignore that line completely for processing because of internal default eol=;.
I'm using ffmpeg to merge videos, I have a bunch *.mp4 and *.m4a with the same name, the manual way to do the conversion is to type the ffmpeg command with the quoted name of the files, I tried to automate and drag and drop both files to merge but I've not being able to pass the file names to variables and then to ffmpeg, I tried this code with quotes, with ! instead of % but no luck, someone know what I'm doing wrong?
#echo off
setlocal ENABLEDELAYEDEXPANSION
set "params=!cmdcmdline!"
set "params=!params:~0,-1!"
set "params=!params:*" =!"
set count=0
for %%G IN (!params!) do (
if %%~xG==.m4a (
set myaudio=%%~G)
if %%~xG==.mp4 (
set myvideo=%%~G )
)
C:\ffmpeg\bin\ffmpeg.exe -y -i "%myaudio%" -i "%myvideo%" -c copy "%myvideo%_new.mp4"
pause
exit
edit: I had wrong syntaxis, as stated on the comments, removing the extra spaces solved the problem
Okay, a brief explanation of what I am doing: I use Windows Media Center (Windows 7) to record Jeopardy every evening. I then use Handbrake to convert the .wtv files to .mkv files and then transfer them to my NAS so I can watch them later using Plex Media Server/Center. Rather than doing this "by hand", I'm trying to automate the process using a batch file as a scheduled task. Initially, I had set up a script so that I could right-click > Send To > convert.bat and it would initiate the command-line interface for Handbrake and convert the file, move the output to my NAS, and delete the original file (worked great).
Now, what I'm doing is initiating the batch script as a scheduled task and looping through the contents of my "recorded tv" directory and looping through any .wtv files to convert/move/delete them.
The problem lies in the fact that Windows Media Center correctly names the Jeopardy files with the "!" in them (Eg: Jeopardy!_KHQ_2012_12_04_21_12_12.wtv), which completely bricks my script. The "Send To" batch file worked great, but when I loop through the *.wtv files in the directory, it returns all the filenames with the "!" stripped out which means I can't do squat with them. Files without "!" do process without a hitch.
Thanks in advance to anyone who can get me pointed in the right direction! (and if you happen to see any other areas where this script could be improved, that's fine too...)
Here is the basic code that I am attempting to use:
#echo off
setlocal ENABLEDELAYEDEXPANSION
SET count=0
SET getFolder=C:\Users\Public\Recorded TV\
SET ripFolder=C:\Rips\
SET putFolder=Z:\Videos\Recorded TV\
FOR %%F IN ("%getFolder%*.wtv") DO (
SET /A count=!count!+1
REM DETERMINE OUTPUT FILENAME
for /f "tokens=5,6,7,8,9,10 delims=\_" %%a in ("%%F") do (
set show=%%a
set station=%%b
set year=%%c
set month=%%d
set day=%%e
set hour=%%f
REM GENERATE OUTPUT NAMING CONVENTION
set output=!show! s!year!e!month!!day! !hour!
)
REM PROCESS WITH HANDBRAKE CLI
"C:\Program Files\Handbrake\HandBrakeCLI.exe" -i "%%F" -t 1 -c 1 -o %ripFolder%!OUTPUT!.mkv -f mkv --deinterlace="fast" --crop 58:60:2:2 --strict-anamorphic -e x264 -q 20 --vfr -a 1 -E faac -B 160 -6 dpl2 -R Auto -D 0 --gain=0 --audio-copy-mask none --audio-fallback ffac3 -x ref=1:weightp=1:subq=2:rc-lookahead=10:trellis=0:8x8dct=0 --verbose=1
REM MOVE CONVERTED FILE TO NAS
copy "%ripFolder%!OUTPUT!.mkv" "%putFolder%"
REM DELETE ORIGINAL
del "%%F"
REM DELETE LOCAL RIP
del "%ripFolder%!output!.mkv"
)
echo %count% files processed
pause
ENDLOCAL
As you have recognized, the exclamation mark is stripped before you can escape it.
That's because you expand the FOR-loop variable %%F while delayed expansion is enabled, and the exclamation mark tries to expand a variable.
You need to toggle the delayed expansion here, as the variable contents are safe when using with delayed expansion, but to get the value you need the disabled mode.
#echo off
setlocal DisableDelayedExpansion
SET count=0
FOR %%F IN ("%getFolder%*.wtv") DO (
set "orgFile=%%F"
SET /A count+=1
REM DETERMINE OUTPUT FILENAME
for /f "tokens=5,6,7,8,9,10 delims=\_" %%a in ("%%F") do (
set show=%%a
set station=%%b
set year=%%c
set month=%%d
set day=%%e
set hour=%%f
setlocal EnableDelayedExpansion
REM GENERATE OUTPUT NAMING CONVENTION
set output=!show! s!year!e!month!!day! !hour!
)
REM PROCESS WITH HANDBRAKE CLI
"C:\Program Files\Handbrake\HandBrakeCLI.exe" -i "%%F" -t 1 -c 1 -o %ripFolder%!OUTPUT!.mkv -f mkv --deinterlace="fast" --crop 58:60:2:2 --strict-anamorphic -e x264 -q 20 --vfr -a 1 -E faac -B 160 -6 dpl2 -R Auto -D 0 --gain=0 --audio-copy-mask none --audio-fallback ffac3 -x ref=1:weightp=1:subq=2:rc-lookahead=10:trellis=0:8x8dct=0 --verbose=1
REM MOVE CONVERTED FILE TO NAS
copy "%ripFolder%!OUTPUT!.mkv" "%putFolder%"
REM DELETE ORIGINAL
del "!orgFile!"
REM DELETE LOCAL RIP
del "%ripFolder%!output!.mkv"
endlocal
)
I have 3 text files like this
file1.txt
AAA1
AAA2
AAA3
...
...
file2.txt
BBB1
BBB2
BBB3
..
..
file3.txt
CCC1
CCC2
CCC3
..
..
I want to have output.txt like this
AAA1:BBB1:CCC1
AAA2:BBB2:CCC2
..
...
now I can do this by making a loop reading a line from each file but I want to do this using sed , grep or any similar tools but I dont know how.
thanks
Use paste:
paste -d ':' file1.txt file2.txt file3.txt
paste is well suited to this task. Try:
paste -d ":" file1.txt file2.txt file3.txt > output.txt
The paste answer sounds like a perfect solution.
But someone (not the OP) might want a native solution that does not require downloading an executable. Something like this really should be done with a more powerful scripting language like VBScript or JScrpt.
But, since I like the challenge of solving things with batch, I thought I'd take a stab at a native batch solution, just for fun.
The OP said "now I can do this by making a loop reading a line from each file". That is easier said than done using batch!
Normally files are read using FOR /F, but there is no good way to interleave reads from multiple files using FOR /F. The only other native alternative is to use SET /P with redirected input. This technique imposes the following limitations:
The input files must use Windows style line terminators: <carriage return><line feed>
No input line can exceed 1021 bytes in length (disregarding the line terminators)
Trailing control characters are stripped from each input line
In addition, each final merged line must not exceed the batch variable length limit of ~8k bytes.
One last restriction - the script can only handle up to 7 input files. The script will fail if more than 7 files are specified - I did not include any error checking.
So here is a working batch script - call it "merge.bat". Note - this batch solution is MUCH slower than other solutions like paste or scripts written in VBScript or JScript. But it does work :-)
#echo off
setlocal disableDelayedExpansion
::Initialization
set "inputRedirection="
set "files=2"
set "lines=0"
for %%F in (%*) do call :setInputRedirection
setlocal enableDelayedExpansion
set "inputRedirection=!inputRedirection:::=<!"
::Merge the files
%inputRedirection% (
for /l %%N in (1 1 %lines%) do (
set "ln="
for /l %%I in (3 1 %files%) do (
call :readLine %%I
if %%I neq %files% (
set "ln=!ln!!input!:"
) else (
echo(!ln!!input!
)
)
)
)
exit /b
:setInputRedirection
set /a "files+=1"
for %%A in (1) do (
set inputRedirection=%files%::"%%~F" %inputRedirection%
for /f %%N in ('find /c /v "" ^<"%%~F"') do if %%N gtr %lines% set "lines=%%N"
)
exit /b
:readLine fileHandle
set "input="
<&%1 set /p "input="
exit /b
To merge your files you would do:
merge.bat file1.txt file2.txt file3.txt >output.txt
This question already has answers here:
Set output of a command as a variable (with pipes) [duplicate]
(6 answers)
Closed 7 years ago.
I need to run a simple find command and redirect the output to a variable in a Windows Batch File.
I have tried this:
set file=ls|find ".txt"
echo %file%
But it does not work.
If I run this command it works without problems:
set file=test.txt
echo %file%
So obviously my command output is not being set to my variable. Can anyone help? Thanks
I just find out how to use commands with pipes in it, here's my command (that extracts the head revision of an svn repo) :
SET SVN_INFO_CMD=svn info http://mySvnRepo/MyProjects
FOR /f "tokens=1 delims=" %%i IN ('%SVN_INFO_CMD% ^| find "Revision"') DO echo %%i
First of all, what you seem to expect from your question isn't even possible in UNIX shells. How should the shell know that ls|find foo is a command and test.txt is not? What to execute here? That's why UNIX shells have the backtick for such things. Anyway, I digress.
You can't set environment variables to multi-line strings from the shell. So we now have a problem because the output of ls wouldn't quite fit.
What you really want here, though, is a list of all text files, right? Depending on what you need it's very easy to do. The main part in all of these examples is the for loop, iterating over a set of files.
If you just need to do an action for every text file:
for %%i in (*.txt) do echo Doing something with "%%i"
This even works for file names with spaces and it won't erroneously catch files that just have a .txt in the middle of their name, such as foo.txt.bar. Just to point out that your approach isn't as pretty as you'd like it to be.
Anyway, if you want a list of files you can use a little trick to create arrays, or something like that:
setlocal enabledelayedexpansion
set N=0
for %%i in (*.txt) do (
set Files[!N!]=%%i
set /a N+=1
)
After this you will have a number of environment variables, named Files[0], Files[1], etc. each one containing a single file name. You can loop over that with
for /l %%x in (1,1,%N%) do echo.!Files[%%x]!
(Note that we output a superfluous new line here, we could remove that but takes one more line of code :-))
Then you can build a really long line of file names, if you wish. You might recognize the pattern:
setlocal enabledelayedexpansion
set Files=
for %%i in (*.txt) do set Files=!Files! "%%i"
Now we have a really long line with file names. Use it for whatever you wish. This is sometimes handy for passing a bunch of files to another program.
Keep in mind though, that the maximum line length for batch files is around 8190 characters. So that puts a limit on the number of things you can have in a single line. And yes, enumerating a whole bunch of files in a single line might overflow here.
Back to the original point, that batch files have no way of capturing a command output. Others have noted it before. You can use for /f for this purpose:
for /f %%i in ('dir /b') do ...
This will iterate over the lines returned by the command, tokenizing them along the way. Not quite as handy maybe as backticks but close enough and sufficient for most puposes.
By default the tokens are broken up at whitespace, so if you got a file name "Foo bar" then suddenly you would have only "Foo" in %%i and "bar" in %%j. It can be confusing and such things are the main reason why you don't ever want to use for /f just to get a file listing.
You can also use backticks instead of apostrophes if that clashes with some program arguments:
for /f "usebackq" %%i in (`echo I can write 'apostrophes'`) do ...
Note that this also tokenizes. There are some more options you can give. They are detailed in the help for command.
set command has /p option that tells it to read a value from standard input. Unfortunately, it does not support piping into it, but it supports reading a value from a first line of existing file.
So, to set your variable to the name of a first *.txt file, you could do the following:
dir /b *.txt > filename.tmp
set /p file=< filename.tmp
del /q filename.tmp
It is important not to add a space before or even after =.
P. S. No fors, no tokens.
Here's a batch file which will return the last item output by find:
#echo off
ls | find ".txt" > %temp%\temp.txt
for /f %%i in (%temp%\temp.txt) do set file=%%i
del %temp%\temp.txt
echo %file%
for has a syntax for parsing command output, for /f "usebackq", but it cannot handle pipes in the command, so I've redirected output to a temporary location.
I strongly recommend, given that you have access to ls, that you consider using a better batch language, such as bash or even an scripting language like python or ruby. Even bash would be a 20x improvement over cmd scripting.
The short answer is: Don't!
A windows shell env var can hold a max of 32 Kb and it isn't safe to save output from programs in them.
That's why you can't. In batch script you must adopt another programming style. If you need all of the output
from the program then save it to file. If you only need to check for certain properties then pipe the output into
a program that does the checking and use the errorlevel mechanism:
#echo off
type somefile.txt | find "somestring" >nul
if %errorlevel% EQU 1 echo Sorry, not found!
REM Alternatively:
if errorlevel 1 echo Sorry, not found!
However, it's more elegant to use the logical operators Perl style:
#echo off
(type somefile.txt | find "somestring" >nul) || echo Sorry, not found!
It's not available in DOS, but in the Windows console, there is the for command. Just type 'help for' at a command prompt to see all of the options. To set a single variable you can use this:
for /f %%i in ('find .txt') do set file=%%i
Note this will only work for the first line returned from 'find .txt' because windows only expands variable once by default. You'll have to enable delayed expansion as shown here.
what you are essentially doing is listing out .txt files. With that, you can use a for loop to over dir cmd
eg
for /f "tokens=*" %%i in ('dir /b *.txt') do set file=%%i
or if you prefer using your ls, there's no need to pipe to find.
for /f "tokens=*" %%i in ('ls *.txt') do set file=%%i
Example of setting a variable from command output:
FOR /F "usebackq" %%Z IN ( `C:\cygwin\bin\cygpath "C:\scripts\sample.sh"` ) DO SET BASH_SCRIPT=%%Z
c:\cygwin\bin\bash -c '. ~/.bashrc ; %BASH_SCRIPT%'
Also, note that if you want to test out the FOR command in a DOS shell, then you need only use %Z instead of %%Z, otherwise it will complain with the following error:
%%Z was unexpected at this time.