Class: Escper::Img

Inherits:
Object
  • Object
show all
Defined in:
lib/escper/image.rb

Instance Method Summary collapse

Constructor Details

#initialize(data, type) ⇒ Img

Returns a new instance of Img.



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# File 'lib/escper/image.rb', line 3

def initialize(data, type)
  if type == :file
    @image = convert(Magick::Image.read(data).first)
  elsif type == :blob
    @image = convert(Magick::Image.from_blob(data).first)
  elsif type == :obj
    @image = convert(data)
  end
end

Instance Method Details

#convert(img = nil) ⇒ Object 



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# File 'lib/escper/image.rb', line 13

def convert(img=nil)
  if img.nil? and @image
    @image = @image.quantize 2, Magick::GRAYColorspace
    @image = crop(@image)
    return @image
  else
    img = img.quantize 2, Magick::GRAYColorspace
    img = crop(img)
    return img
  end
end

#crop(image) ⇒ Object 



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# File 'lib/escper/image.rb', line 25

def crop(image)
  @x = (image.columns / 8.0).round
  @y = (image.rows / 8.0).round
  @x = 1 if @x == 0
  @y = 1 if @y == 0
  image = image.extent @x * 8, @y * 8
  return image
end

#to_a ⇒ Object 



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# File 'lib/escper/image.rb', line 34

def to_a
  colorarray = @image.export_pixels
  return colorarray
end

#to_s ⇒ Object 



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# File 'lib/escper/image.rb', line 39

def to_s
  colorarray = self.to_a
  bits = []
  mask = 0x80
  i = 0
  temp = 0
  (@x * @y * 8 * 3 * 8).times do |j|
    next unless (j % 3).zero?
    temp |= mask if colorarray[j] == 0 # put 1 in place if black
    mask = mask >> 1 # shift mask
    i += 3
    if i == 24
      bits << temp
      mask = 0x80
      i = 0
      temp = 0
    end
  end
  result = bits.pack("C*")
  p_cmd = "\x1D\x76\x30\x00"
  hdr = [@x, (@y*8)].pack("SS")
  escpos = ''
  escpos.encode! 'ASCII-8BIT'
  escpos += p_cmd + hdr + result
  return escpos
end