Automatically tag Fujifilm raw files with the correct film simulation

fujicolor.rb

#!/usr/bin/ruby

require 'shellwords'
require 'thread'

paths = Queue.new
ARGV.each { |path| paths << path }

# http://www.sno.phy.queensu.ca/~phil/exiftool/TagNames/FujiFilm.html

COLOR_CAMERA_PROFILES = {
  'Classic Chrome' => 'Camera CLASSIC CHROME',
  'Pro Neg. Hi' => 'Camera Pro Neg. Hi',
  'Pro Neg. Std' => 'Camera Pro Neg. Std',
  'F1b/Studio Portrait Smooth Skin Tone (Astia)' => 'Camera ASTIA/SOFT',
  'F0/Standard (Provia)' => 'Camera PROVIA/STANDARD',
  'F2/Fujichrome (Velvia)' => 'Camera Velvia/VIVID',
}.freeze

BW_CAMERA_PROFILES = {
  'None (B&W)' => 'Camera MONOCHROME',
  'B&W Green Filter' => 'Camera MONOCHROME+G FILTER',
  'B&W Red Filter' => 'Camera MONOCHROME+R FILTER',
  'B&W Yellow Filter' => 'Camera MONOCHROME+Ye FILTER',
}.freeze

def camel_case(str)
  str.to_s.gsub(/^\w|(?:_\w)/) { |c| c[-1, 1].upcase }
end

def snake_case(str)
  key.gsub!(/^\w| \w/, &:downcase)
  key.gsub!(' ', '_')
end

def extract_metadata(path, *fields)
  flags = fields.map { |f| '-' << camel_case(f) }
  command = ['exiftool', '-t', *flags, path]
  result = %x(#{Shellwords.join(command)})
  if $?.exitstatus == 0
    result.lines.each_with_object({}) do |line, acc|
      key, value = line.chomp.split("\t")
      key.gsub!(/^\w| \w/, &:downcase)
      key.gsub!(' ', '_')
      acc[key.to_sym] = value
    end
  else
    raise "Could not extract metadata: exiftool exited with #{$?.exitstatus} (#{result.inspect})"
  end
end

def update_metadata(path, fields)
  flags = fields.map { |k, v| '-' << camel_case(k) << '=' << v }
  command = ['exiftool', '-overwrite_original_in_place', *flags, path]
  result = %x(#{Shellwords.join(command)})
  if $?.exitstatus != 0
    raise "Could not update metadata: exiftool exited with #{$?.exitstatus} (#{result.inspect})"
  end
end

def find_camera_profile(meta_data)
  COLOR_CAMERA_PROFILES[meta_data[:film_mode]] || BW_CAMERA_PROFILES[meta_data[:saturation]]
end

threads = Array.new(4) do
  Thread.start do
    paths << :die
    while (raw_path = paths.pop) != :die
      xmp_path = File.join(File.dirname(raw_path), File.basename(raw_path, '.*')) << '.xmp'
      raw_meta_data = extract_metadata(raw_path, :film_mode, :saturation)
      if File.exist?(xmp_path)
        xmp_meta_data = extract_metadata(xmp_path, :camera_profile, :camera_profile_digest)
      else
        xmp_meta_data = {}
      end
      camera_profile = find_camera_profile(raw_meta_data)
      if camera_profile && !xmp_meta_data.include?(:camera_profile)
        $stderr.puts(sprintf('%s updated film simulation ("%s")', xmp_path, camera_profile))
        update_metadata(xmp_path, camera_profile: camera_profile)
      elsif !camera_profile
        $stderr.puts(sprintf('%s could not detect film simulation (film mode was "%s", saturation was "%s")', raw_path, raw_meta_data[:film_mode], raw_meta_data[:saturation]))
      elsif (camera_profile = xmp_meta_data[:camera_profile])
        $stderr.puts(sprintf('%s already has a camera profile ("%s")', xmp_path, camera_profile))
      end
    end
  end
end
threads.each(&:value)