How to batch rename images, in reverse numerical order?

Solution 1:

You can use an Automator Workflow.

Something like this:

Sort Finder Items step will sort image names descending (IMG_0003.jpg, IMG_002.jpg, IMG_001.jpg).

Make Sequential step will rename them sequentially (IMG_0001.jpg, IMG_0002.jpg, ...).

Copy Finder Items step is optional, just to be sure not to mess with original files.

Solution 2:

Here's another shell script. You can save it as a normal text file and then run bash /path/to/script.sh from Terminal. Remove the echo to actually rename the files.

cd ~/Pictures/
IFS=$'\n' # the input field separators include space by default
i=1
for f in $(ls -r IMG*.jpg); do 
    echo mv "$f" "IMG_$(printf %04d $i)".jpg
    (( i++ ))
done