Module: ChunkyPNG

Extended by:
ChunkyPNG
Included in:
ChunkyPNG
Defined in:
lib/chunky_png.rb,
lib/chunky_png/chunk.rb,
lib/chunky_png/image.rb,
lib/chunky_png/pixel.rb,
lib/chunky_png/palette.rb,
lib/chunky_png/datastream.rb,
lib/chunky_png/pixel_matrix.rb,
lib/chunky_png/pixel_matrix/decoding.rb,
lib/chunky_png/pixel_matrix/encoding.rb

Overview

ChunkyPNG

The ChunkyPNG module defines some constants that are used in the PNG specification.

Defined Under Namespace

Classes: Chunk, Datastream, Image, Palette, Pixel, PixelMatrix

Constant Summary collapse

COLOR_GRAYSCALE =

PNG international standard defined constants

0
COLOR_TRUECOLOR = 
2
COLOR_INDEXED = 
3
COLOR_GRAYSCALE_ALPHA = 
4
COLOR_TRUECOLOR_ALPHA = 
6
FILTERING_DEFAULT = 
0
COMPRESSION_DEFAULT = 
0
INTERLACING_NONE = 
0
INTERLACING_ADAM7 = 
1
FILTER_NONE = 
0
FILTER_SUB = 
1
FILTER_UP = 
2
FILTER_AVERAGE = 
3
FILTER_PAETH = 
4

Instance Method Summary collapse

Instance Method Details

#load(arg) ⇒ Object 



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# File 'lib/chunky_png.rb', line 55

def load(arg)
  if arg.respond_to?(:read)
    load_from_io(arg)
  elsif File.exists?(arg)
    load_from_file(arg)
  else
    load_from_memory(arg)
  end
end

#load_from_file(file) ⇒ Object 



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# File 'lib/chunky_png.rb', line 47

def load_from_file(file)
  File.open(file, 'r') { |f| load_from_io(f) }
end

#load_from_io(io) ⇒ Object 



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# File 'lib/chunky_png.rb', line 43

def load_from_io(io)
  ChunkyPNG::Datastream.read(io)
end

#load_from_memory(string) ⇒ Object 



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# File 'lib/chunky_png.rb', line 51

def load_from_memory(string)
  load_from_io(StringIO.new(string))
end