class FileData::Box

Mpeg4 box

Attributes

content_stream[R]
end_pos[R]
type[R]

Public Class Methods

new(type, content_stream) click to toggle source
# File lib/file_data/formats/mpeg4/box.rb, line 8
def initialize(type, content_stream)
  @type = type
  @content_stream = content_stream
  @end_pos = @content_stream.end_pos
end
parse(view) click to toggle source
# File lib/file_data/formats/mpeg4/box.rb, line 14
def self.parse(view)
  type, pos, size = parse_header(view)
  new(type, Helpers::SubStreamView.new(view.stream, pos, size))
end
parse_header(view) click to toggle source
# File lib/file_data/formats/mpeg4/box.rb, line 19
def self.parse_header(view)
  start_pos = view.pos
  first_field = view.read_value(4)
  type = view.read_ascii(4)

  total_size =
    if first_field == 1
      view.read_value(8)
    else
      first_field
    end

  content_pos = view.pos
  header_size = content_pos - start_pos
  content_size = total_size - header_size

  [type, content_pos, content_size]
end