mjhjmtu

I would like to know if there's a command that can tell me how much storage are the .jpg files (for example). Something like if I do find / -iname "*.jpg" which can add the size of each file found and output a total.

find ./path/to/your/drive -type f -name '*.jpg' -exec du -ch +

Or much faster

find /path/to/your/drive -name "*.jpg" -print0 | du -ch --files0-from=-

Or simply,

du -ch /path/to/your/drive/*.jpg | grep total

Or with help of awk,

find /path/to/your/drive -iname "*.jpg" -ls | awk 'total += $7 END print total'

On my system file size shows on seventh field, if it's different for you then adjust accordingly.

As requested by OP in comment, if you want to find all images from a directory and total size you can use this command (suggested by @Stéphane Chazelas)

 find . -type f -exec file --mime-type + | sed -n 's|: image/[^[:blank:]]*$||p' | tr 'n' '' | du --files0-from=- -hc

Or

 du -shc $(find . -name '*' -exec file ; | grep -o -P '^.+: w+ image' | cut -d':' -f1) | grep total

As an alternative, you can do this using only POSIX:

find . -type f -name "*.jpg" -exec du -sk ; |
 awk 'BEGINtotal=0;total += $1; ENDprintf "%.3f MBn", total / 1024'

Further reading:

• 
  du - estimate file space usage (POSIX)


• 
  find - find files (POSIX)