How can I strip the audio track out of a video file with FFmpeg?
5 Answers
You remove audio by using the -an
flag:
input_file=example.mkv
output_file=example-nosound.mkv
ffmpeg -i $input_file -c copy -an $output_file
This ffmpeg flag is documented here.
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3I'm a
bash
andffmpeg
newbie but I put this answer together with some other pieces to createfunction ffsilent { ffmpeg -i $1 -c copy -an "$1-nosound.${1#*.}" }
which you can use in your profile to quickly create a silent version of any video file.– AaronDec 16, 2019 at 15:18 -
7@Aaron nice, but should be
function ffsilent { ffmpeg -i "$1" -c copy -an "${1%.*}-nosound.${1#*.}" }
or you'll end up with "file.mp4-nosound.mp4" when using it on "file.mp4". Jul 7, 2020 at 8:52 -
1
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Using
-c copy -an
works on most video files but it won't strip audio from SWF (Shockwave Flash) files. The solution is to shorten it to just-an
then it works.– bat_cmdApr 4, 2021 at 0:18 -
3@rlittles Yes,
-c copy
always avoids re-encoding, If it can't it will fail with an error. Jul 10, 2022 at 0:35
You probably don't want to reencode the video (a slow and lossy process), so try:
input_file=example.mkv
output_file=example-nosound.mkv
ffmpeg -i $input_file -vcodec copy -an $output_file
(n.b. some Linux distributions now come with the avconv fork of ffmpeg)
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2This didn't make any difference to me compared to the accepted solution.– nidiDec 29, 2017 at 0:49
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6vcodec is an alias for
-c:v
, so specifically it'd copy the video stream only. The only data you're preventing with this would be subtitles, metadata, etc from what I can see.– RogueMar 8, 2018 at 15:48 -
3In other words, this solution can conceivably lose more information than the accepted solution.– AlexFeb 25, 2020 at 15:12
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2
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2I agree: This here is the "copy video only" solution, whereas the accepted answer is the "copy everything but audio" solution.– porgNov 9, 2022 at 19:03
avconv -i [input_file] -vcodec copy -an [output_file]
If you cannot install ffmpeg
because of existing of avconv
try that .
I put together a short code snippet that automates the process of removing audio from videos files for a whole directory that contains video files:
FILES=/{videos_dir}/*
output_dir=/{no_audio_dir}
for input_file in $FILES
do
file_name=$(basename $input_file)
output_file="$output_dir/$file_name"
ffmpeg -i $input_file -c copy -an $output_file
done
I hope this one helps!
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Out of interest, how would I use this snippet when there are spaces in the video dir (and output dir)? Aug 12, 2022 at 14:26
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@PaulSkinner adding quotes should be enough eg:
file_name=$(basename "$input_file")
– GeorgeJan 6 at 13:27
I have taken @apolak's answer and turned it in to a recursive loop for all folders underneath the input folder. It will retain the directory layout of the input folder, and you can set a max-depth for it to recurse through. The output directory must not be a child of the input directory or it will error, to stop accidental infinite recursion. It should also be fine with spaces in filenames and paths.
NOTE: all files within the input directory will be attempted to be processed, so make sure they're all video files.
#!/bin/bash
process_files() {
local current_dir="$1"
local output_dir="$2"
local max_depth="$3"
local depth="${4:-0}" # Set default value of 0 if $4 is not set
if [ "$depth" -gt "$max_depth" ]; then
return
fi
# Check if output directory is a subdirectory of the input directory and error
# This should stop accidental recursive loops
if [[ "$output_dir" == "$current_dir"* ]]; then
echo "Error: Output directory is a subdirectory of the input directory"
exit 1
fi
mkdir -p "$output_dir"
for input_file in "$current_dir"/*
do
if [ -d "$input_file" ]; then
# If the input file is a directory, recurse into it
process_files "$input_file" "$output_dir/$(basename "$input_file")" "$max_depth" "$((depth+1))"
elif [ -f "$input_file" ]; then
# If the input file is a regular file, process it
local file_name=$(basename "$input_file")
local output_file="$output_dir/$file_name"
ffmpeg -i "$input_file" -c copy -an "$output_file"
fi
done
}
# Call function with input and output directories and maximum depth
process_files "/Volumes/Storage/ORIGINAL" "/Volumes/Storage/MUTED" 2 # Set the maximum recursion depth to 2