Sorting files by date

My phone saves pictures with names in the format

IMG_YYYYMMDD_HHMMSS.jpg

I upload all images to my machine in a single directory, but I want to sort them by date. I use the following commands to sort them, in two phases :

First, create the directories

ls|cut -d_ -f2|sort -u|while read date; do
mkdir -p /data/pictures/${date:0:4}/${date:0:4}-${date:4:2}-${date:6:2};
done

• ls gives all image names
• cut -d_ -f2 extracts the date of each picture
• sort -u removes duplicate dates with the -u (unique) option
• while read date loops on all dates to run the next command
• mkdir -p creates the directory for the date, and eventually the year
• The syntax ${date:0:4} extract parts of the date. In this case the year

Then move images into directories

ls|cut -d_ -f2|sort -u|while read date; do
mv *$date* /data/pictures/${date:0:4}/${date:0:4}-${date:4:2}-${date:6:2};
done

Only the command inside the loop is different :

• mv *$date* moves all pictures of the same day in the target directory

If the date is not in the file name, but is available in the directory, you can get it with the command ls --full-time and parse the output, or you can use the command stat to get exactly what you want, as it gives you full control on the output.