Class: Barby::QrCode

Inherits:
Barcode2D show all
Defined in:
lib/barby/barcode/qr_code.rb

Overview

QrCode is a thin wrapper around the RQRCode library

Constant Summary collapse

SIZES =

Maximum sizes for each correction level for binary data It’s an array

{
        #L   M   Q   H
  1  => [17, 14, 11, 7],          2  => [32, 26, 20, 14],
  3  => [53, 42, 32, 24],         4  => [78, 62, 46, 34],
  5  => [106, 84, 60, 44],        6  => [134, 106, 74, 58],
  7  => [154, 122, 86, 64],       8  => [192, 152, 108, 84],
  9  => [230, 180, 130, 98],      10 => [271, 213, 151, 119],
  11 => [321, 251, 177, 137],     12 => [367, 287, 203, 155],
  13 => [425, 331, 241, 177],     14 => [458, 362, 258, 194],
  15 => [520, 412, 292, 220],     16 => [586, 450, 322, 250],
  17 => [644, 504, 364, 280],     18 => [718, 560, 394, 310],
  19 => [792, 624, 442, 338],     20 => [858, 666, 482, 382],
  21 => [929, 711, 509, 403],     22 => [1003, 779, 565, 439],
  23 => [1091, 857, 611, 461],    24 => [1171, 911, 661, 511],
  25 => [1273, 997, 715, 535],    26 => [1367, 1059, 751, 593],
  27 => [1465, 1125, 805, 625],   28 => [1528, 1190, 868, 658],
  29 => [1628, 1264, 908, 698],   30 => [1732, 1370, 982, 742],
  31 => [1840, 1452, 1030, 790],  32 => [1952, 1538, 1112, 842],
  33 => [2068, 1628, 1168, 898],  34 => [2188, 1722, 1228, 958],
  35 => [2303, 1809, 1283, 983],  36 => [2431, 1911, 1351, 1051],
  37 => [2563, 1989, 1423, 1093], 38 => [2699, 2099, 1499, 1139],
  39 => [2809, 2213, 1579, 1219], 40 => [2953, 2331, 1663, 1273]
}.sort
LEVELS = 
{ :l => 0, :m => 1, :q => 2, :h => 3 }

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from Barcode

#method_missing, #outputter_class_for, #outputter_for, outputters, register_outputter, #two_dimensional?, #valid?

Constructor Details

#initialize(data, options = {}) ⇒ QrCode

Returns a new instance of QrCode.

Raises:

  • (ArgumentError) 


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# File 'lib/barby/barcode/qr_code.rb', line 42

def initialize(data, options={})
  self.data = data
  @level, @size = nil
  options.each{|k,v| send("#{k}=", v) }
  raise(ArgumentError, "data too large") unless size
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method in the class Barby::Barcode

Instance Attribute Details

#data ⇒ Object

Returns the value of attribute data.



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# File 'lib/barby/barcode/qr_code.rb', line 38

def data
  @data
end

#level ⇒ Object

Error correction level Can be one of [:l, :m, :q, :h] (7%, 15%, 25%, 30%)



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# File 'lib/barby/barcode/qr_code.rb', line 62

def level
  @level || :l
end

#size ⇒ Object 



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# File 'lib/barby/barcode/qr_code.rb', line 67

def size
  #@size is only used for manual override, if it's not set
  #manually the size is always dynamic, calculated from the
  #length of the data
  return @size if @size

  level_index = LEVELS[level]
  length = data.bytesize
  found_size = nil
  SIZES.each do |size,max_values|
    if max_values[level_index] >= length
      found_size = size
      break
    end
  end
  found_size
end

Instance Method Details

#encoding ⇒ Object 



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# File 'lib/barby/barcode/qr_code.rb', line 55

def encoding
  rqrcode.modules.map{|r| r.inject(''){|s,m| s << (m ? '1' : '0') } }
end

#to_s ⇒ Object 



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# File 'lib/barby/barcode/qr_code.rb', line 86

def to_s
  data[0,20]
end