Grabs the H.264 version of a video from YouTube.

gistfile1.rb

require 'curb'
require 'cgi'

def youtube_url(video_id)
  c = Curl::Easy.new("http://www.youtube.com/watch?v=#{video_id}")
  c.cookies = 'PREF: f2=40000000;'
  c.perform

  content = c.body_str
  matches = content.match(/"fmt_url_map":\s"([^"]*)"/)

  if matches
    matches[1].split(',').each do |line|
      parts = line.split('|')
      id = parts[0].to_i
      if id == 18
        link = parts[1]
        link.gsub!(/\\u0026/, '&')
        link.gsub!(/\\\//, '/')
        return CGI::unescape(link)
      end
    end
  end
  
  nil
end

puts youtube_url("NJOIR0slR_c")