How to batch rename 40000 files on a folder with number count

Question

I need to batch rename 40000 files on a folder with a number count in the end like this:. something.jpg to something_00001.jpg. I\'d like to work with the rename command, but an

Answer 1

These are powerful commands that will make lots of changes very rapidly - please test on a copy of a small subset of your data.

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Method 1 - Using "rename" (Perl tool)

This should work with rename which you can install on macOS with:

brew install rename

The command would be:

rename --dry-run -N "00001" 's/.jpg$/_$N.jpg/' *jpg

Remove the --dry-run to actually execute the command rather than just tell you what it would do.

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Method 2 - Using GNU Parallel

Alternatively, this should work with GNU Parallel which you can install on macOS with:

brew install parallel

The command would be:

find . -name \*.jpg -print0 | parallel -0 --dry-run mv {} {.}_{#}.jpg

where:

• {} means "the current file",
• {.} means "the current file minus extension", and
• {#} means "the (sequential) job number"

Remove the --dry-run to actually execute the command rather than just tell you what it would do.

You mentioned you wanted an offset, so the following works with an offset of 3:

find . -name \*.jpg -print0 | parallel -0  'printf -v new "%s_%05d.jpg" "{.}" $(({#}+3)); echo mv "{}" "$new"'

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Method 3 - No additional software required

This should work using just standard, built-in tools:

#!/bin/bash

for f in *.jpg; do
   # Figure out new name
   printf -v new "%s_%05d.jpg" "${f%.jpg}" $((cnt+=1))

   echo Would rename \"$f\" as \"$new\"
   #mv "$f" "$new"
done

Remove the # in the penultimate line to actually do the rename.

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Method 4 - No additional software required

This should work using just standard, built-in tools. Note that macOS comes with Perl installed, and this should be faster as it doesn't start a new mv process for each of 40,000 files like the previous method. Instead, Perl is started just once, it reads the null-terminated filenames passed to it by find and then executes a library call for each:

find . -name \*.jpg -print0 | perl -0 -e 'while(<>){ ($sthg=$_)=~s/.jpg//; $new=sprintf("%s_%05d.jpg",$sthg,++$cnt); printf("Rename $_ as $new\n"); }'

If that looks correct, change the last line so it actually does the rename rather than just telling you what it would do:

find . -name \*.jpg -print0 | perl -0 -e 'while(<>){ ($sthg=$_)=~s/.jpg//; $new=sprintf("%s_%05d.jpg",$sthg,++$cnt); mv $_, $new; }'

Answer 2

Here's a solution using renamer.

$ tree
.
├── beach.jpg
├── sky.jpg

$ renamer --path-element name --index-format %05d --find /$/ --replace _{{index}} *

$ tree
.
├── beach_00001.jpg
├── sky_00002.jpg