Remove double prefix from filenames

Question

I have files nested in folders. In case the filename starts with a string that is repeated twice, I would like to change the filename to a name such that this string appears only once.

For example:

Rename "Dirty Projectors - Dirty Projectors - Search For Life.mp3" to "Dirty Projectors - Search For Life.mp3"
Rename "Eefje de Visser - Eefje de Visser - Bitterzoet.mp3" to "Eefje de Visser - Bitterzoet.mp3"
Keep "Feng Suave - Maybe Another Time.mp3" as it is.

How can I do this using command-line in Linux?

If you have the Perl `rename` command, you can use a regular expression that matches a string followed by the same string, by using back-references. — Barmar, May 05 '20 at 14:52
`s/^(.*)\1/\1/` will replace a duplicate string at the beginning of a filename. — Barmar, May 05 '20 at 14:52
Note that this means that if the filename begins with `ee` it will change to `e`. If you want the match to end with `-` you need to be more specific. — Barmar, May 05 '20 at 14:53
@Barmar, do you mean something like `perl-rename 's/^(.*)\\1/\\1/' *.mp3`? — sryscad, May 05 '20 at 20:54

score 1 · Accepted Answer · answered May 06 '20 at 17:41

I combined the regex of @Barmar and the shell script of @U880D to remove any duplicate prefix in the filenames recursively. There was a problem with using find and perl-rename, so I had to do it like this:

#!/bin/bash
shopt -s globstar;
for DIR in ${PWD}/**/; do
    cd "${DIR}"
    for FILENAME in *.mp3 ; do
        NEWFILENAME=$(echo "${FILENAME}" | perl -pe 's/^(.*)\1/\1/')
        if [ "${FILENAME}" != "${NEWFILENAME}" ] ; then
            mv "${FILENAME}" "${NEWFILENAME}"
        fi
    done
done

U880D · Answer 2 · 2023-03-17T10:38:49.657

0

How can I do this using command-line in Linux?

After some research it seems to be a bit more complex. Therefore it will probably end up in a script.

renameMusic.sh

#!/bin/bash

DIRECTORY=$1
cd ${DIRECTORY}
echo "Normalize filenames in $(pwd)"

for FILENAME in *; do
  echo
  echo "Checking file ${FILENAME}"

  # Count number of dash (-)
  NUMBER=$(grep -o '-' <<< ${FILENAME} | wc -l)
  echo "Found ${NUMBER} of dash (-)"
  
  # Check if the artist name seems to be there twice
  if [[ "${NUMBER}" -eq 2 ]]; then
    # If so, remove the double part
    NEWFILENAME=$(echo "${FILENAME}" | cut -d "-" -f 2- | sed -e 's/^[[:space:]]*//')
    echo "Going to move to new name ${NEWFILENAME}"

    # mv ${FILENAME} ${NEWFILENAME}

  fi

done

Thanks to

edited Mar 17 '23 at 10:38

answered May 05 '20 at 16:19

U880D

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Please take note that I've commented out the renaming part so that it will be possible to have a dry run. I my test setup and test run it worked well. Since you have mentioned that "_I have files nested in folders._", I will leave that part to you. – U880D May 05 '20 at 16:22
Thank you, this works in case I put quotes around the arguments of the mv command. – sryscad May 05 '20 at 19:32
1

You should always quote your variables unless you have a good reason not to. – Barmar May 05 '20 at 21:50
@U880D, Actually It does not work in case the folder name contains a dash. I have tried to write `find -name "*.mp3" -type f -printf '%P\n' | xargs perl-rename 's/^(.*)\1/\1/'` but it does not change the names. It only works when I use it without the find. – sryscad May 05 '20 at 21:51
Thanks for the hint [When to wrap quotes around a shell variable?](https://stackoverflow.com/questions/10067266/). I'll put it into the credits. – U880D May 06 '20 at 04:52
@sryscad, you may take advantage from [How to loop through file names returned by find?](https://stackoverflow.com/questions/9612090/). So by enhancing the script with `# Make sure globstar is enabled shopt -s globstar for i in **/*.mp3; do # Whitespace-safe and recursive` it would work. At least it did in my test setup. – U880D May 06 '20 at 05:14

Remove double prefix from filenames

2 Answers2