Class: PDF417

Inherits:
Object
  • Object
show all
Defined in:
lib/pdf417.rb

Defined Under Namespace

Classes: GenerationError, Lib

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(*attrs) ⇒ PDF417

Returns a new instance of PDF417.



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# File 'lib/pdf417.rb', line 16

def initialize(*attrs)
  # TODO:  Test these defaults, make sure that they can get set on init, check to see that the output changes accordingly
  self.text = ""
  @y_height = 3
  @aspect_ratio = 0.5
  @rows = 1
  @cols = 0
  
  if attrs.first.is_a?(String)
    self.text = attrs.first
  elsif attrs.first.is_a?(Hash)      
    attrs.first.each do |k,v|
      if self.respond_to?("#{k}=".to_sym)
        self.send("#{k}=".to_sym, v)
      end
    end
  end

  @blob = nil
end

Instance Attribute Details

#bit_columns ⇒ Object (readonly)

Returns the value of attribute bit_columns.



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# File 'lib/pdf417.rb', line 14

def bit_columns
  @bit_columns
end

#bit_length ⇒ Object (readonly)

Returns the value of attribute bit_length.



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# File 'lib/pdf417.rb', line 14

def bit_length
  @bit_length
end

#bit_rows ⇒ Object (readonly)

Returns the value of attribute bit_rows.



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# File 'lib/pdf417.rb', line 14

def bit_rows
  @bit_rows
end

Class Method Details

.encode_text(text) ⇒ Object 



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# File 'lib/pdf417.rb', line 9

def encode_text(text)
  PDF417::Lib.encode_text(text)
end

Instance Method Details

#aspect_ratio ⇒ Object

Aspect ratio



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# File 'lib/pdf417.rb', line 70

def aspect_ratio
  @aspect_ratio
end

#aspect_ratio=(val) ⇒ Object 



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# File 'lib/pdf417.rb', line 73

def aspect_ratio=(val)
  @blob = nil
  @aspect_ratio = val
end

#codewords ⇒ Object 



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# File 'lib/pdf417.rb', line 55

def codewords
  return @raw_codewords if !@raw_codewords.nil?
  @codewords ||= self.class.encode_text(text)
end

#cols ⇒ Object

Make the barcode at least this number of columns



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# File 'lib/pdf417.rb', line 97

def cols
  @cols
end

#cols=(val) ⇒ Object 



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# File 'lib/pdf417.rb', line 100

def cols=(val)
  @blob = nil
  @cols = val
end

#encoding ⇒ Object 



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# File 'lib/pdf417.rb', line 183

def encoding
  self.generate! if @blob.nil?
  
  # This matches the output from the pdf417 lib sample output.
  enc = self.blob.bytes.to_a.each_slice(self.bit_rows).to_a[0..(self.rows-1)] # sometimes we get more rows than expected, truncate
  
  # The length returned here is too long and we have extra data that gets padded w/ zeroes, meaning it doesn't all match.
  # Eg, instead of ending with "111111101000101001" it ends with "1111111010001010010000000".
  return enc.collect do |row_of_bytes|
    row_of_bytes.collect{|x| sprintf("%08b", x)}.join[0..self.bit_columns-1]
  end
end

#encoding_to_s ⇒ Object 



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# File 'lib/pdf417.rb', line 196

def encoding_to_s
  self.encoding.each{|x| puts x.gsub("0"," ")}
end

#error_level ⇒ Object

Request the specified error level must be between 0 and 8



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# File 'lib/pdf417.rb', line 106

def error_level
  @error_level
end

#error_level=(val) ⇒ Object 



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# File 'lib/pdf417.rb', line 109

def error_level=(val)
  @blob = nil
  @error_level = val
end

#generate! ⇒ Object 



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# File 'lib/pdf417.rb', line 114

def generate!
  lib = Lib.new(text)
  options = []
  # Setting the text via accessor will set the codewords to nil, but if they have
  # been manually set pass them on.
  if @raw_codewords.is_a?(Array)
    lib.raw_codewords = @raw_codewords
    lib.generation_options |= Lib::PDF417_USE_RAW_CODEWORDS
    options << 'raw codewords'
  end
  
  if self.rows.to_i > 0 && self.cols.to_i > 0
    lib.code_rows = self.rows.to_i
    lib.code_cols = self.cols.to_i
    lib.generation_options |= Lib::PDF417_FIXED_RECTANGLE
    options << "#{rows}x#{cols}"
  elsif self.rows.to_i > 0
    lib.code_rows = self.rows.to_i 
    lib.generation_options |= Lib::PDF417_FIXED_ROWS
    options << "#{rows} rows"
  elsif self.cols.to_i > 0
    lib.code_cols = self.cols.to_i
    lib.generation_options |= Lib::PDF417_FIXED_COLUMNS
    options << "#{cols} cols"
  end

  if self.error_level.to_i >= 0 && self.error_level.to_i <= 8
    lib.error_level = self.error_level.to_i
    lib.generation_options |= Lib::PDF417_USE_ERROR_LEVEL
    options << "requested #{error_level.to_i} error level"
  end

  lib.aspect_ratio = self.aspect_ratio.to_f
  lib.y_height = self.y_height.to_f

  (@blob = lib.to_blob) 
  if @blob.nil? || @blob.empty?
    if lib.generation_error == Lib::PDF417_ERROR_TEXT_TOO_BIG
      raise GenerationError, "Text is too big"
    elsif lib.generation_error == Lib::PDF417_ERROR_INVALID_PARAMS
      msg = "Invalid parameters: #{options.join(', ')}"
      if lib.generation_options & Lib::PDF417_USE_RAW_CODEWORDS && lib.raw_codewords.length != lib.raw_codewords.first
        msg +=".  The first element of the raw codwords must be the length of the array.  Currently it is #{lib.raw_codewords.first}, perhaps it should be #{lib.raw_codewords.length}?"
      end
      raise GenerationError, msg
    else
      raise GenerationError, "Could not generate bitmap error: #{options.join(', ')}"
    end
  else
    @codewords = lib.codewords
    @bit_columns = lib.bit_columns
    @bit_rows = ((lib.bit_columns - 1) / 8) + 1
    @bit_length = lib.bit_length
    @rows = lib.code_rows 
    @cols = lib.code_cols
    @error_level = lib.error_level
    @aspect_ratio = lib.aspect_ratio
    @y_height = lib.y_height
    return true
  end
end

#inspect ⇒ Object 



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# File 'lib/pdf417.rb', line 37

def inspect
  "#<#{self.class.name}:#{self.object_id} >"
end

#raw_codewords ⇒ Object

For setting the codewords directly



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# File 'lib/pdf417.rb', line 79

def raw_codewords
  @raw_codewords
end

#raw_codewords=(val) ⇒ Object 



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# File 'lib/pdf417.rb', line 82

def raw_codewords=(val)
  @blob = nil
  @raw_codewords = val
end

#rows ⇒ Object

Make the barcode at least this number of rows



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# File 'lib/pdf417.rb', line 88

def rows
  @rows
end

#rows=(val) ⇒ Object 



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# File 'lib/pdf417.rb', line 91

def rows=(val)
  @blob = nil
  @rows = val
end

#text ⇒ Object 



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# File 'lib/pdf417.rb', line 47

def text
  if @raw_codewords.nil?
    @text
  else
    ""
  end
end

#text=(val) ⇒ Object 



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# File 'lib/pdf417.rb', line 42

def text=(val)
  @codewords = @blob = nil
  @text = val
end

#to_blob ⇒ Object Also known as: blob 



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# File 'lib/pdf417.rb', line 177

def to_blob
  self.generate! if @blob.nil?
  @blob    
end

#to_png(opts = {}) ⇒ Object 



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# File 'lib/pdf417.rb', line 200

def to_png(opts = {})
  require 'chunky_png' unless defined?(ChunkyPNG)
  
  self.generate! if @blob.nil?
  opts[:x_scale] ||= 1
  opts[:y_scale] ||= 3
  opts[:margin] ||= 10
  full_width = (self.bit_columns * opts[:x_scale]) + (opts[:margin] * 2)
  full_height = (self.rows * opts[:y_scale]) + (opts[:margin] * 2)
  
  canvas = ChunkyPNG::Image.new(full_width, full_height, ChunkyPNG::Color::WHITE)

  x, y = opts[:margin], opts[:margin]
  booleans = encoding.map{|l| l.split(//).map{|c| c == '1' } }
  booleans.each do |line|
    line.each do |bar|
      if bar
        x.upto(x+(opts[:x_scale]-1)) do |xx|
          y.upto y+(opts[:y_scale]-1) do |yy|
            canvas[xx,yy] = ChunkyPNG::Color::BLACK
          end
        end
      end
      x += opts[:x_scale]
    end
    y += opts[:y_scale]
    x = opts[:margin]
  end
  canvas.to_datastream.to_s    
end

#y_height ⇒ Object

Y Height



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# File 'lib/pdf417.rb', line 61

def y_height
  @y_height
end

#y_height=(val) ⇒ Object 



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# File 'lib/pdf417.rb', line 64

def y_height=(val)
  @blob = nil
  @y_height = val
end