convert.rb

#!/usr/bin/env ruby

require 'set'

files = Dir.glob('**/*.ARW') + Dir.glob('**/*.RAF')
files.each { |old_file| 
  new_file = "#{File.join(File.dirname(old_file), File.basename(old_file, File.extname(old_file)))}.heic"
  if File.exist?(new_file)
    puts "Deleting #{old_file}"
    File.delete(old_file)
  else
    puts `sips -s format heic "#{old_file}" -s formatOptions best --out "#{new_file}"` 
  end
}

puts "All existing extensions:"
files = Dir.glob('**/*').filter { |path| File.file?(path) }
extnames = Set.new
files.each { |file|
  extnames.add(File.extname(file))
}
puts extnames.to_a.join(",")