Module: Oil

Defined in:
lib/oil.rb

Defined Under Namespace

Classes: JPEGReader, PNGReader

Constant Summary collapse

VERSION = 
"0.1.3"

Class Method Summary collapse

Class Method Details

.new(io, box_width, box_height) ⇒ Object 



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# File 'lib/oil.rb', line 17

def self.new(io, box_width, box_height)
  case sniff_signature(io)
  when :JPEG
    return new_jpeg_reader(io, box_width, box_height)
  when :PNG
    return new_png_reader(io, box_width, box_height)
  else
    raise "Unknown image file format."
  end
end

.sniff_signature(io) ⇒ Object 



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# File 'lib/oil.rb', line 4

def self.sniff_signature(io)
  a = io.getc
  b = io.getc
  io.ungetc(b)
  io.ungetc(a)

  if (a == "\xFF".b && b == "\xD8".b)
    return :JPEG
  elsif (a == "\x89".b && b == "P".b)
    return :PNG
  end
end