.ebextensions file for AWS Elastic Beanstalk ImageMagick --with-webp --quantum-depth 8 --disable-openmp

01-packages.config

packages:
  yum:
    bzip2-devel: []
    freetype-devel: []
    gcc: []
    ghostscript-devel: []
    GraphicsMagick: []
    libpng-devel: []
    libjpeg-turbo-devel: []
    libwebp-devel: []
    libtiff-devel: []
    tcl-devel: []

sources:
  /etc/ImageMagick: http://www.imagemagick.org/download/ImageMagick.tar.gz

files:
  "/etc/install_imagemagick.sh":
    mode: "000755"
    owner: root
    group: root
    content: |
      #!/bin/sh -x
      if [ "1" == $(convert -list format | grep WEBP | wc -l) ]; then
        echo Good ImageMagick already installed.
        exit 0
      fi
      cd /etc/ImageMagick/ImageMagick-*
      # webp
      # disabling openmp seems to improve things roughly 25%.
      # quantum depth 8 improved performance by roughly 20%
      ./configure --prefix=/usr --with-webp=yes --disable-openmp --with-quantum-depth=8
      make
      make install
      /sbin/ldconfig /usr/local/lib

commands:
  01_remove_imagemagick:
    command: yum -y remove ImageMagick
  02_run_install_imagemagick_script:
    command: /etc/install_imagemagick.sh

Unfortunately, this increases instance start time from 2-3 minutes to 10-15 minutes.
I recommend creating a custom base AMI if you want reasonable autoscaling.

Based on https://forums.aws.amazon.com/thread.jspa?messageID=673907 among other sources