This is a wee bit dangerous when used in isolation. It will search for all files that *nix believes is an image and will then use imagemin (npm install -g imagemin if you need it) to begin optimizing assuming the defaults are worth trusting. This is not lossless. It does make a backup of each file inside the current working directory inside, con…

overwrite-images-with-optimized-images.sh

#!/bin/sh

mkdir backup;
for file in $(
  find . -exec \
  file {} \; | \
  awk -F':' '{ if ($2 ~/[Ii]mage|EPS/) print $1,"\n"}'| \
  sed s/\.//);
do
  cp  -R -v .$file ./backup/;
  imagemin .$file > .$file.tmp;
  mv -f .$file.tmp .$file;
done