Compress all PNG or JPG files of a folder thanks to TinyPNG or TinyJPG API

compress_image.sh

#!/bin/bash
# Install
# This script need a API key from TinyPNG. See this page: https://tinypng.com/developers
# It also need jq library, which can be install thanks to: `brew install jq`

# Usage
# cd to your folder. This script will compress all PNG or JPG files recursively.

API_KEY="CHANGE_ME"

if [ $API_KEY = "CHANGE_ME" ]
then
  echo "CHANGE THE API_KEY in this file."
  exit 1
fi

if ! type "jq" > /dev/null
then
  echo "Please install `jq`"
  exit 1
fi

find . -type f \( -name  \*.jpg -o -name \*.png -o -name \*.jpeg \) -print0 | while IFS= read -r -d '' file; do
  echo "Compress file: $file"

  json=$(curl -sS --user api:$API_KEY --data-binary @$file https://api.tinypng.com/shrink)
  url=$(jq -n "$json.output.url" | sed -e 's/^"//'  -e 's/"$//')

  echo "Compression OK. Old size: $(jq -n "$json.input.size"), new size: $(jq -n "$json.output.size"), ratio: $(jq -n "$json.output.ratio")"
  echo "Downloading the compressed file…"

  curl -sS $url > $file

  echo "Compressed file downloaded with success!"
done

Added the support of filename with blank characters : https://gist.github.com/Diwann/aefcb54e205bc531a9de

I found oxipng to be very useful for this task.