Class: ZIMG::Image

Inherits:
Object
  • Object
show all
Includes:
DeepCopyable
Defined in:
lib/zimg/image.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from DeepCopyable

#deep_copy

Constructor Details

#initialize(x, h = {}) ⇒ Image

possible input params:

IO      of opened image file
String  with image file already readed
Hash    of image parameters to create new blank image



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# File 'lib/zimg/image.rb', line 16

def initialize(x, h = {})
  @chunks = []
  @color_class = Color
  @extradata = []
  @verbose =
    case h[:verbose]
    when true then  1
    when false then 0
    else h[:verbose].to_i
    end

  case x
  when IO
    _from_io x
  when String
    _from_io StringIO.new(x)
  when Hash
    # XXX currently implicitly creates PNG
    extend PNG
    @format = :png
    _from_hash x
  else
    raise NotSupported, "unsupported input data type #{x.class}"
  end
end

Instance Attribute Details

#bpp ⇒ Object (readonly)

Returns the value of attribute bpp.



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# File 'lib/zimg/image.rb', line 9

def bpp
  @bpp
end

#chunks ⇒ Object (readonly)

Returns the value of attribute chunks.



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# File 'lib/zimg/image.rb', line 9

def chunks
  @chunks
end

#color_class ⇒ Object (readonly)

Returns the value of attribute color_class.



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# File 'lib/zimg/image.rb', line 9

def color_class
  @color_class
end

#format ⇒ Object (readonly)

Returns the value of attribute format.



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# File 'lib/zimg/image.rb', line 9

def format
  @format
end

#height ⇒ Object (readonly)

Returns the value of attribute height.



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# File 'lib/zimg/image.rb', line 9

def height
  @height
end

#metadata ⇒ Object (readonly)

Returns the value of attribute metadata.



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# File 'lib/zimg/image.rb', line 9

def metadata
  @metadata
end

#palette ⇒ Object (readonly)

Returns the value of attribute palette.



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# File 'lib/zimg/image.rb', line 9

def palette
  @palette
end

#scanlines ⇒ Object

Returns the value of attribute scanlines.



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# File 'lib/zimg/image.rb', line 10

def scanlines
  @scanlines
end

#verbose ⇒ Object (readonly)

Returns the value of attribute verbose.



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# File 'lib/zimg/image.rb', line 9

def verbose
  @verbose
end

#width ⇒ Object (readonly)

Returns the value of attribute width.



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# File 'lib/zimg/image.rb', line 9

def width
  @width
end

Instance Method Details

#==(other) ⇒ Object 



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# File 'lib/zimg/image.rb', line 86

def ==(other)
  return false unless other.is_a?(Image)
  return false if width  != other.width
  return false if height != other.height

  each_pixel do |c, x, y|
    return false if c != other[x, y]
  end
  true
end

#[](x, y) ⇒ Object 



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# File 'lib/zimg/image.rb', line 108

def [](x, y)
  scanlines[y][x]
end

#_from_io(io) ⇒ Object

Raises:



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# File 'lib/zimg/image.rb', line 42

def _from_io(io)
  io.binmode

  fmt = nil
  hdr = String.new
  ZIMG.magics.keys.sort_by(&:size).each do |magic|
    hdr << io.read(magic.size - hdr.size) if magic.size > hdr.size
    if hdr == magic
      fmt = ZIMG.magics[magic]
      break
    end
  end

  raise NotSupported, "Unsupported header #{hdr.inspect} in #{io.inspect}" unless fmt

  @format = fmt
  m = ZIMG.const_get(fmt.to_s.upcase)
  extend(m)
  send("read_#{fmt}", io)

  return if io.eof?

  offset     = io.tell
  @extradata << io.read
  return unless @verbose >= 1

  warn "[?] #{@extradata.last.size} bytes of extra data after image end (IEND), offset = 0x#{offset.to_s(16)}".red
end

#alpha_used? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/zimg/image.rb', line 137

def alpha_used?
  false
end

#each_pixel(&block) ⇒ Object 



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# File 'lib/zimg/image.rb', line 97

def each_pixel(&block)
  e = Enumerator.new do |ee|
    height.times do |y|
      width.times do |x|
        ee.yield(self[x, y], x, y)
      end
    end
  end
  block_given? ? e.each(&block) : e
end

#imagedata_size ⇒ Object 



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# File 'lib/zimg/image.rb', line 78

def imagedata_size
  if new_image?
    @scanlines&.map(&:size)&.inject(&:+)
  else
    imagedata&.size
  end
end

#inspect ⇒ Object 



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# File 'lib/zimg/image.rb', line 112

def inspect
  info =
    %w[format width height bpp colorspace chunks scanlines].map do |k|
      next unless respond_to?(k)

      v = case (v = send(k))
          when Array
            v.empty? ? "[]" : "[#{v.size} entries]"
          when String
            v.size > 40 ? "[#{v.bytesize} bytes]" : v.inspect
          else v.inspect
          end
      "#{k}=#{v}"
    end.compact.join(", ")
  Kernel.format("#<ZIMG::Image %s>", info)
end

#new_image? ⇒ Boolean Also known as: new?

flag that image is just created, and NOT loaded from file as in Rails’ ActiveRecord::Base#new_record?

Returns:

  • (Boolean) 


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# File 'lib/zimg/image.rb', line 73

def new_image?
  @new_image
end

#pixels ⇒ Object 



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# File 'lib/zimg/image.rb', line 133

def pixels
  Pixels.new(self)
end

#to_ascii(*args) ⇒ Object 



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# File 'lib/zimg/image.rb', line 129

def to_ascii *args
  scanlines&.map { |l| l.to_ascii(*args) }&.join("\n")
end