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batch-filecmdffmpeg

Redirecting ffmpeg output to a file

I Want to make a script that using ffmpeg looks for errors in files. But I can't redirect the output of ffmpeg to a file, it always displays errors in the console. my script:

@echo off
set LOGFILE=error_check.log
call :LOG > %LOGFILE%
exit /B

:LOG
for /r %%A IN (*.mp4) DO (
    echo "%%A"
    ffmpeg.exe -hwaccel auto -v error -i "%%A" -f null - 
)
exit

I tried redirecting the output of ffmpeg using ">>", but that didn't work either. I also tried using the option -report together with -loglevel error in ffmpeg, but it outputs way too much I only want error information.

Solution

  • > is an abbreviation for 1>, which redirects STDOUT.

    Errors usually are printed to STDERR, which is stream 2. To redirect STDERR, use 2>.

    To redirect both, use 1>... 2>&1 (STDOUT to ..., STDERR to wherever STDOUT is redirected to)

    A fully detailed description is available at SS64