ffmpeg: Transcoding multiple input files to multiple output files with single command

Question

I want to convert three files with a single command. I used the following command:

-i "C:\fil1.mp4" -i "C:\file2.mp4" -i "C:\file3.mp4" -acodec libmp3lame -ab 32k -ar 22050 -ac 2 -b:v 128k -r 20 -s 176x144 -y file1.mp4 -acodec libmp3lame -ab 32k -ar 22050 -ac 2 -b:v 128k -r 20 -s 176x144 -y file2.mp4 -acodec libmp3lame -ab 32k -ar 22050 -ac 2 -b:v 128k -r 20 -s 176x144 -y file3.mp4

but it converts the first files with names fil1.mp4, fil2.mp4, fil3.mp4 but I want all files should be convert with its output file names.

Solution 1

Using -map helps with specifying which input goes with which output.

I used this code to convert multiple audio files:

ffmpeg -i infile1 -i infile2 -map 0 outfile1 -map 1 outfile2

also use -map_metadata to specify the metadata stream:

ffmpeg -i infile1 -i infile2 -map_metadata 0 -map 0 outfile1 -map_metadata 1 -map 1 outfile2

Solution 2

I wrote bash script for it.

You can modify as you want:

#!/bin/sh

BASE_DIR=$HOME/Videos/mov
OUTPUT_DIR=$BASE_DIR/avi
FILES=$(ls $BASE_DIR | grep .MOV)

for FILE in $FILES
do
    FILENAME="${FILE:0:-4}"
    ffmpeg -i $BASE_DIR/$FILE $OUTPUT_DIR/$FILENAME.avi
done

Solution 3

I have tried David Blum's script, there was a problem with spaces in filenames. Here's my modified script that uses basename to remove the file extension from filenames. It operates on the current directory, assuming a subdirectory called 'avi':

#!/bin/sh

OUTPUT_DIR=./avi

#IFS=$'\n'  # split only on newlines
for FILE in *MOV
do
    FILENAME=`basename "${FILE}" .MOV`
    ffmpeg -i  "$FILE" "$OUTPUT_DIR/$FILENAME.avi"
    #echo $FILENAME
done

Solution 4

find ./ -name "*.wav" -exec ffmpeg -i {} -c:a libopus {}.opus \;

View more solutions

Comments

[Matthias Braun]

With Bash you can use brace expansion to run ffmpeg on a range of files: for i in MVI_{2967..2970}.MOV; do ffmpeg -i "$i" -crf 24 ~/"$i"; done

[Abubakar]

Thank you for involvement. cubitouch you can see my command fulfill the criteria which is given in FFMPEG documentation as ffmpeg -i input1 -i input2\ -acodec .. -vcodec .. output1\ -acodec .. -vcodec .. output2\ -acodec .. -vcodec .. output3.

[cubitouch]

@Abubakar Why don't you try factorise the "-acodec libmp3lame -ab 32k -ar 22050 -ac 2 -b:v 128k -r 20 -s 176x144" part, and try parallelize the encodings ?

[Abubakar]

Sorry i could not do that.

[cubitouch]

And what about Parallel Encoding ? (see ffmpeg.org/pipermail/ffmpeg-user/2013-April/014898.html)

[Edmund Rojas]

Is it possible to do this with creating multiple videos from multiple audio files and a single image? -y -i input1.mp3 -i input2.mp3 -f image2 -loop 1 -r 2 -i imagefile.png -shortest -c:a aac -c:v mpeg4 -crf 18 -preset veryfast -movflags faststart -map 0 output1.mp4 -map1 output2.mp4

[Isaac Abramowitz]

Hmm not sure. Probably. If you can't find a question like that already posted, I would suggest posing that question on this site.

[double-beep]

While this code may solve the question, including an explanation of how and why this solves the problem would really help to improve the quality of your post, and probably result in more up-votes. Remember that you are answering the question for readers in the future, not just the person asking now. Please edit your answer to add explanations and give an indication of what limitations and assumptions apply.

[llogan]

Consider checking your (overly complex) script with shellcheck.net. There are several issues to address.

[Hugh W]

The question explicitly states that ffmpeg should only be invoked once. Your solution invokes it once per input file.

[Matthias Braun]

This might help you simplify this command.