Create a movie using ffmpeg

Create movie from a set of images.

class MovieBuilder
  include FileUtils

  def initialize(image_directory = '.', image_type = 'png')
    @base_dir = image_directory
    @temp_dir = "#{@base_dir}/temp"
    @image_type = image_type
  end
  
  def make(movie_name, frame_rate = 5)
    rm_rf @temp_dir
    mkdir @temp_dir

    Dir.glob("*.#{@image_type}").sort.each_with_index do | file, index |
      frame = sprintf('%03d',index + 1)
      cp File.join(@base_dir, file), File.join(@temp_dir, "#{frame}.#{@image_type}")
    end

    `ffmpeg -y -r #{frame_rate} -i #{File.join(@temp_dir, "%03d.#{@image_type}")} #{File.join(@base_dir, movie_name)}`
  end
end

MovieBuilder.new.make 'my-project-movie.mp4', 3