exifdater.rb

#!/usr/bin/env ruby
#
# Runs through a folder and prepends all photo filenames with date and time
#
# Author:: Soon Van <cog@randomecho.com>
# Copyright:: Copyright 2013 Soon Van
# License:: BSD 3-Clause License <http://opensource.org/licenses/BSD-3-Clause>
#
# Usage: 
#
#  $ exifdater.rb path/to/photos

require 'exifr/jpeg'

@found_count = 0
@rename_count = 0
@datemod_count = 0
@skip_count = 0
@error_count = 0

def cleanup_filenames_with_date_modified(photo_dir)
  Dir.foreach(photo_dir) do |photo|
    if is_valid_photo(photo)
      remove_date_modified(photo, photo_dir)
    end
  end
end

def is_valid_photo(filename)
  return File.extname(filename).downcase.match(/\.jpe?g/)
end

def remove_date_modified(photo, photo_dir)
  photo_base = photo_dir + File::SEPARATOR
  photo_file = photo_base + photo
  photo_modified = EXIFR::JPEG.new(photo_file).date_time
  photo_taken = EXIFR::JPEG.new(photo_file).date_time_original

  if !photo_modified.nil? && photo_taken != photo_modified
    datetime_modified = photo_modified.strftime("%Y%m%d_%H%M%S")

    if File.fnmatch('*' + datetime_modified + '*', photo)
      filename_without_date_modified = photo_file.sub(datetime_modified, '')
      filename_without_date_modified.sub!('--', '-')

      begin
        File.rename(photo_file, filename_without_date_modified)
        @datemod_count += 1
      rescue
        @error_count += 1
      end
    end
  end
end

def rename_photo(photo, photo_dir)
  photo_base = photo_dir + File::SEPARATOR
  photo_file = photo_base + photo
  photo_taken = EXIFR::JPEG.new(photo_file).date_time_original

  unless photo_taken.nil?
    photo_stamp = photo_taken.strftime("%Y%m%d_%H%M%S")

    if File.fnmatch(photo_stamp + '*', photo)
      @skip_count += 1
    else
      begin
        File.rename(photo_file, photo_base + photo_stamp + '-' + photo)
        @rename_count += 1
      rescue
        @error_count += 1
      end
    end
  else
    @error_count += 1
  end
end

def exifdater(photo_dir)
  if File.directory?(photo_dir)
    Dir.foreach(photo_dir) do |photo|
      if is_valid_photo(photo)
        @found_count += 1

        rename_photo(photo, photo_dir)
      end
    end

    cleanup_filenames_with_date_modified(photo_dir)
  end
end

if ARGV[0].nil?
  puts "! No folder specified."
  puts "Use the following format: \n\n"
  puts " exifdater.rb path/to/photos"
  exit
else
  exifdater(ARGV[0])
  puts "\nLet's go marking dates in photos..."
  puts @found_count.to_s + " found"
  puts @rename_count.to_s + " renamed"
  
  if @skip_count > 0
    puts @skip_count.to_s + " skipped, date already in filename"
  end

  if @datemod_count > 0
    puts @datemod_count.to_s + " renamed to remove date_modified from filename"
  end

  if @error_count > 0
    puts @error_count.to_s + " photos could not be renamed"
  end
end