Timelapse deshaker

deshake.rb

#!/usr/bin/env ruby

# brew install imagemagick
# brew install Caskroom/cask/hugin

require 'fileutils'
require 'thread'
require 'optparse'

ALIGN_COMMAND_PATH = '/usr/local/Caskroom/hugin/2014.0.0/HuginTools/align_image_stack'

reference_frame = nil
output_dir = 'aligned'
parallelism = 4

parser = OptionParser.new do |p|
  p.on('--reference-frame PATH') { |s| reference_frame = s }
  p.on('--output-dir PATH') { |s| output_dir = s }
  p.on('--parallelism P') { |s| parallelism = s.to_i }
end
parser.parse!(ARGV)

if ARGV.empty?
  abort('No frames')
elsif Dir.exist?(output_dir)
  abort('Output directory exists')
end

class Aligner
  def initialize(reference_frame, output_dir)
    @reference_frame = reference_frame
    @output_dir = output_dir
  end

  def align(frame)
    file_name = File.basename(frame, '.*')
    prefix = sprintf('%s/tmp-%s-', @output_dir, file_name)
    command = [ALIGN_COMMAND_PATH, '-a', prefix, @reference_frame, frame]
    Process.wait(spawn(*command, out: '/dev/null'))
    output_frames = Dir["#{prefix}*"]
    aligned_frame = sprintf('%s/%s.jpg', @output_dir, file_name)
    command = ['convert', output_frames.last, '-shave', '16x9', aligned_frame]
    Process.wait(spawn(*command, out: '/dev/null'))
    output_frames.each { |path| FileUtils.rm(path) }
  end
end

aligner = Aligner.new(reference_frame || ARGV.first, output_dir)

frames = Queue.new

ARGV.each { |path| frames << path }

FileUtils.mkdir(output_dir)

io_lock = Mutex.new

threads = Array.new(parallelism) do
  Thread.start do
    while (frame = frames.pop) != :die
      aligner.align(frame)
      io_lock.synchronize do
        $stderr.puts("Created #{File.basename(frame)}")
      end
    end
  end
end

threads.each do
  frames << :die
end

begin
  threads.each(&:value)
rescue => e
  io_lock.synchronize do
    $stderr.puts("#{e.message} (#{e.class.name})")
    $stderr.puts(e.backtrace.join("\t\n"))
  end
  exit(1)
end