Recover your .skitch files

skitch2image.rb

#!/usr/bin/env ruby

# Prereq:
# gem install ox

# Usage:
# cd my_skitch_directory
# ./sktich2image.rb

# Warning #1: This doesn't check for the target .png/.jpg, etc, it just writes to the same filename as the skitch but with a png/jpg extension.

# Warning #2: None of the skitch annotations will end up in the image. Sorry! If you find a way to automate the newer skitch app to process a directory of images, let me know

# I wanted to use nokogiri, but libxml has an attribute value max length
# which caused issues since our images are embedded in an attribute
# => [#<Nokogiri::XML::SyntaxError: 5:10000134: FATAL: AttValue length too long>, #<Nokogiri::XML::SyntaxError: 5:10000134: FATAL: Memory allocation failed>, #<Nokogiri::XML::SyntaxError: 5:10000134: FATAL: attributes construct error>, #<Nokogiri::XML::SyntaxError: 5:10000134: FATAL: Couldn't find end of Start Tag image line 5>]

require 'ox'
require "base64"

Dir["*.skitch"].each do |skitch_filename|
  File.open(skitch_filename) do |skitch_file|
    puts "processing #{skitch_filename}..."
    doc = Ox.parse(IO.read(skitch_file))
    attribute = doc.locate('svg/image/@xlink:href').first
  
    prefix, data = attribute.split(',', 2)

    # prefix looks like "data:image/png;base64"
    extension = prefix.partition('/').last.split(';').first
  
    file_to_write = skitch_file.to_path.gsub('.skitch', "." + extension)
    puts "writing #{file_to_write}"
    File.open(file_to_write, "wb") do |f|
      f.write(Base64.decode64(data))
    end
    File.utime(File.atime(skitch_filename), File.mtime(skitch_filename), file_to_write)
  end
end