Convert images recursively to webp

convertwebp.rb

#!/usr/bin/env ruby

# Convert images recursively to webp

require 'fileutils'

CONVERTERS = {
  'cwebp'          => '-q 80 "%s" -m 6 -o "%s"',
  'magick convert' => '-quality 80 -define webp:method=6 "%s" "%s"'
}

converter = CONVERTERS.find { |cmd, params| system("#{cmd} -version") }

Dir.glob('**/*.{jpg,png,JPG}').each do |image|
  webp_img = image.sub(/\.(jpg|png|JPG)$/, '.webp')
  if converter && !File.exist?(webp_img)
    mtime = File.mtime(image)
    success = system("#{converter[0]} #{sprintf(converter[1], image, webp_img)}")
    FileUtils.touch(webp_img, :mtime => mtime) if success
    system("rm \"#{image}\"") if success
  end
end