a simple script to fix mp3 tags which have euc-kr encoding issues

fixtag.rb

#!/usr/bin/env ruby

require 'optparse'
require 'mp3info'
require 'taglib'

ID3_TAGS = [:title, :artist, :album]

options = {}
OptionParser.new do |opts|
  opts.banner = 'Usage: fixtag.rb [options] [FILE|DIR]'
  options[:dry_run] = false
  opts.on('-d', '--dry-run', 'do not save files') do |d|
    options[:dry_run] = true
  end
end.parse!

def euckr_to_utf8(str)
  begin
    str.force_encoding('euc-kr').encode('utf-8')
  rescue
    nil
  end
end

def update_file(fn, dry_run)
  tags = {}
  Mp3Info.open(fn) do |f|
    ID3_TAGS.each do |tn|
      converted = euckr_to_utf8(f.tag.send(tn))
      tags[tn] = converted if converted
    end
  end

  puts tags

  if dry_run
    return
  end

  frame_factory = TagLib::ID3v2::FrameFactory.instance
  frame_factory.default_text_encoding = TagLib::String::UTF8

  f = TagLib::MPEG::File.new(fn)
  tag = f.id3v2_tag
  tags.each do |tn, v|
    tag.send("#{tn}=", v)
  end
  f.save
end

def main(args, dry_run)
  args.each do |arg|
    if File.file? arg
      update_file(arg, dry_run)
    elsif File.directory? arg
      Dir.foreach(arg) do |fn|
        update_file(File.join(arg, fn), dry_run) unless fn.start_with? '.'
      end
    end
  end
end

begin
  main(ARGV, options[:dry_run])
end

Gemfile

source "http://rubygems.org"

gem "ruby-mp3info"
gem "taglib-ruby"

Gemfile.lock

GEM
  remote: http://rubygems.org/
  specs:
    ruby-mp3info (0.6.16)
    taglib-ruby (0.2.1)

PLATFORMS
  ruby

DEPENDENCIES
  ruby-mp3info
  taglib-ruby