module Media

media processing requires a different type of tempfile… because we use command line tools to process our temp files, these files can't be open and closed by ruby.

instead, Media::TempFile is used to generate closed files from binary data (for files to be fed to command line tools), or to generate empty tmp files (for output filenames to be fed to command line tools).

We use the Tempfile class for generating these files, but then we always close them right away. By doing this, we ensure that the temp file will eventually get removed when the Tempfile gets garbage collected.

Constants

GRAPHICSMAGICK_COMMAND
GRAPHICSMAGICK_VERSION
INKSCAPE_COMMAND
LIBREOFFICE_COMMAND
VERSION

Public Class Methods

dimensions(filepath) click to toggle source

# File lib/media.rb, line 56
def self.dimensions(filepath)
  return unless Media::GraphicsMagickTransmogrifier.available?
  Media::GraphicsMagickTransmogrifier.dimensions filepath
end

has_dimensions?(mime_type) click to toggle source

special graphicsmagick hooks. we use graphicsmagick in order to parse the dimensions of image files.

# File lib/media.rb, line 51
def self.has_dimensions?(mime_type)
  Media::GraphicsMagickTransmogrifier.available? &&
    Media::GraphicsMagickTransmogrifier.converts_from?(mime_type)
end

may_produce?(src_type, dst_type) click to toggle source

# File lib/media.rb, line 42
def self.may_produce?(src_type, dst_type)
  Transmogrifier.find_class(src_type, dst_type)
end

transmogrifier(options) click to toggle source

creates a new instance of transmogrifier suitable for turning input into output.

# File lib/media.rb, line 15
def self.transmogrifier(options)
  if options[:input_type]
    input_type = Media::MimeType.simple options[:input_type]
  elsif options[:input_file]
    input_type = Media::MimeType.mime_type_from_extension options[:input_file]
  else
    raise ArgumentError.new
  end

  if options[:output_type]
    output_type = Media::MimeType.simple options[:output_type]
  elsif options[:output_file]
    output_type = Media::MimeType.mime_type_from_extension options[:output_file]
  else
    raise ArgumentError.new
  end

  unless input_type and output_type
    raise ArgumentError.new("Both input and output types are required (given %s -> %s)." % [input_type||'nil', output_type||'nil'])
  end

  transmog_class = Transmogrifier.find_class(input_type, output_type)
  if transmog_class
    transmog_class.new(options)
  end
end