Contents

module M3u8
  class PlaylistItem
    attr_accessor :program_id, :width, :height, :codecs, :bitrate, :playlist,
                  :audio, :level, :profile
    MISSING_CODEC_MESSAGE = 'Audio or video codec info should be provided.'

    def initialize(params = {})
      params.each do |key, value|
        instance_variable_set("@#{key}", value)
      end
    end

    def resolution
      return if width.nil?
      "#{width}x#{height}"
    end

    def codecs
      return @codecs unless @codecs.nil?

      audio_codec = audio_codec audio
      video_codec = video_codec profile, level

      if video_codec.nil?
        return audio_codec
      else
        if audio_codec.nil?
          return video_codec
        else
          return "#{video_codec},#{audio_codec}"
        end
      end
    end

    def to_s
      validate
      "#EXT-X-STREAM-INF:PROGRAM-ID=#{program_id},#{resolution_format}" +
        %(CODECS="#{codecs}",BANDWIDTH=#{bitrate}\n#{playlist})
    end

    private

    def validate
      fail MissingCodecError, MISSING_CODEC_MESSAGE if codecs.nil?
    end

    def resolution_format
      return if resolution.nil?
      "RESOLUTION=#{resolution},"
    end

    def audio_codec(audio)
      return if audio.nil?
      return 'mp4a.40.2' if audio.downcase == 'aac-lc'
      return 'mp4a.40.5' if audio.downcase == 'he-aac'
      return 'mp4a.40.34' if audio.downcase == 'mp3'
    end

    def video_codec(profile, level)
      return if profile.nil? || level.nil?

      profile = profile.downcase
      return 'avc1.66.30' if profile == 'baseline' && level == 3.0
      return 'avc1.42001f' if profile == 'baseline' && level == 3.1
      return 'avc1.77.30' if profile == 'main' && level == 3.0
      return 'avc1.4d001f' if profile == 'main' && level == 3.1
      return 'avc1.4d0028' if profile == 'main' && level == 4.0
      return 'avc1.64001f' if profile == 'high' && level == 3.1
      return 'avc1.640028' if profile == 'high' &&
                              (level == 4.0 || level == 4.1)
    end
  end
end

Version data entries

3 entries across 3 versions & 1 rubygems

Version	Path
m3u8-0.3.1	lib/m3u8/playlist_item.rb
m3u8-0.3.0	lib/m3u8/playlist_item.rb
m3u8-0.2.1	lib/m3u8/playlist_item.rb