Class: Qrio::QrMatrix

Inherits:
Matrix
  • Object
show all
Defined in:
lib/qrio/qr_matrix.rb

Constant Summary collapse

FORMAT_MASK = 
0b101_0100_0001_0010
ERROR_CORRECTION_LEVEL = 
%w( M L H Q )
MODE = 
{
  1 => :numeric,
  2 => :alphanumeric,
  4 => :ascii,
  8 => :kanji
}
WORD_WIDTHS = 
{
  :numeric      => { 1..9 => 10, 10..26 => 12, 27..40 => 14 },
  :alphanumeric => { 1..9 =>  9, 10..26 => 11, 27..40 => 13 },
  :ascii        => { 1..9 =>  8, 10..26 => 16, 27..40 => 16 },
  :kanji        => { 1..9 =>  8, 10..26 => 10, 27..40 => 12 }
}
ALIGNMENT_CENTERS = 
[
  [],
  [6, 18],
  [6, 22],
  [6, 26],
  [6, 30],
  [6, 34],
  [6, 22, 38],
  [6, 24, 42],
  [6, 26, 46],
  [6, 28, 50],

  [6, 30, 54],
  [6, 32, 58],
  [6, 34, 62],
  [6, 26, 46, 66],
  [6, 26, 48, 70],
  [6, 26, 50, 74],
  [6, 30, 54, 78],
  [6, 30, 56, 82],
  [6, 30, 58, 86],
  [6, 34, 62, 90],

  [6, 28, 50, 72, 94],
  [6, 26, 50, 74, 98],
  [6, 30, 54, 78, 102],
  [6, 28, 54, 80, 106],
  [6, 32, 58, 84, 110],
  [6, 30, 58, 86, 114],
  [6, 34, 62, 90, 118],
  [6, 26, 50, 74,  98, 122],
  [6, 30, 54, 78, 102, 126],
  [6, 26, 52, 78, 104, 130],

  [6, 26, 52, 78, 104, 130],
  [6, 30, 56, 82, 108, 134],
  [6, 34, 60, 86, 112, 138],
  [6, 30, 58, 86, 114, 142],
  [6, 34, 62, 90, 118, 146],
  [6, 30, 54, 78, 102, 126, 150],
  [6, 24, 50, 76, 102, 128, 154],
  [6, 28, 54, 80, 106, 132, 158],
  [6, 32, 58, 84, 110, 136, 162],
  [6, 26, 54, 82, 110, 138, 166],
  [6, 30, 58, 86, 114, 142, 170]
]
BLOCK_STRUCTURE = 
[
  # to determine block structure, find the row corresponding to QR version
  # (row 0 = version 1), then find the column corresponding to ECC level
  # (M / L / H / Q)
  #
  # the result array will be:
  #   * block count
  #   * number of data bytes per block
  #   * nubmer of error correction bytes per block
  #   * (optional) number of blocks with one additional data byte
  #
  [[ 1, 16, 10    ], [ 1,  19,  7    ], [ 1,  9, 17    ], [ 1, 13, 13,   ]],
  [[ 1, 28, 16    ], [ 1,  34, 10    ], [ 1, 16, 28    ], [ 1, 22, 22,   ]],
  [[ 1, 44, 26    ], [ 1,  55, 15    ], [ 2, 13, 22    ], [ 2, 17, 18,   ]],
  [[ 2, 32, 18    ], [ 1,  80, 20    ], [ 4,  9, 16    ], [ 2, 24, 26,   ]],
  [[ 2, 43, 24    ], [ 1, 108, 26    ], [ 2, 11, 22,  2], [ 2, 15, 18,  2]],
  [[ 4, 27, 16    ], [ 2,  68, 18    ], [ 4, 15, 28,   ], [ 4, 19, 24,   ]],
  [[ 4, 31, 18    ], [ 2,  78, 20    ], [ 4, 13, 26,  1], [ 2, 14, 18,  4]],
  [[ 2, 38, 22,  2], [ 2,  97, 24    ], [ 4, 14, 26,  2], [ 4, 18, 22,  2]],
  [[ 3, 36, 22,  2], [ 2, 116, 30    ], [ 4, 12, 24,  4], [ 4, 16, 20,  4]],
  [[ 4, 43, 26,  1], [ 2,  68, 18,  2], [ 6, 15, 28,  2], [ 6, 19, 24,  2]],

  [[ 1, 50, 30,  4], [ 4,  81, 20    ], [ 3, 12, 24,  8], [ 4, 22, 28,  4]],
  [[ 6, 36, 22,  2], [ 2,  92, 24,  2], [ 7, 14, 28,  4], [ 4, 20, 26,  6]],
  [[ 8, 37, 22,  1], [ 4, 107, 26    ], [12, 11, 22,  4], [ 8, 20, 24,  4]],
  [[ 4, 40, 24,  5], [ 3, 115, 30,  1], [11, 12, 24,  5], [11, 16, 20,  5]],
  [[ 5, 41, 24,  5], [ 5,  87, 22,  1], [11, 12, 24,  7], [ 5, 24, 30,  7]],
  [[ 7, 45, 28,  3], [ 5,  98, 24,  1], [ 3, 15, 30, 13], [15, 19, 24,  2]],
  [[10, 46, 28,  1], [ 1, 107, 28,  5], [ 2, 14, 28, 17], [ 1, 22, 28, 15]],
  [[ 9, 43, 26,  4], [ 5, 120, 30,  1], [ 2, 14, 28, 19], [17, 22, 28,  1]],
  [[ 3, 44, 26, 11], [ 3, 113, 28,  4], [ 9, 13, 26, 16], [17, 21, 26,  4]],
  [[ 3, 41, 26, 13], [ 3, 107, 20,  5], [15, 15, 28, 10], [15, 24, 30,  5]],

  [[17, 42, 26    ], [ 4, 116, 28,  4], [19, 16, 30,  6], [17, 22, 28,  6]],
  [[17, 46, 28    ], [ 2, 111, 28,  7], [34, 13, 24,   ], [ 7, 24, 30, 16]],
  [[ 4, 47, 28, 14], [ 4, 121, 30,  5], [16, 15, 30, 14], [11, 24, 30, 14]],
  [[ 6, 45, 28, 14], [ 6, 117, 30,  4], [30, 16, 30,  2], [11, 24, 30, 16]],
  [[ 8, 47, 28, 13], [ 8, 106, 26,  4], [22, 15, 30, 13], [ 7, 24, 30, 22]],
  [[19, 46, 28,  4], [10, 114, 28,  2], [33, 16, 30,  4], [28, 22, 28,  6]],
  [[22, 45, 28,  3], [ 8, 122, 30,  4], [12, 15, 30, 28], [ 8, 23, 30, 26]],
  [[ 3, 45, 28, 23], [ 3, 117, 30, 10], [11, 15, 30, 31], [ 4, 24, 30, 31]],
  [[21, 45, 28,  7], [ 7, 116, 30,  7], [19, 15, 30, 26], [ 1, 23, 30, 37]],
  [[19, 47, 28, 10], [ 5, 115, 30, 10], [23, 15, 30, 25], [15, 24, 30, 25]],

  [[ 2, 46, 28, 29], [13, 115, 30,  3], [23, 15, 30, 28], [42, 24, 30,  1]],
  [[10, 46, 28, 23], [17, 115, 30    ], [19, 15, 30, 35], [10, 24, 30, 35]],
  [[14, 46, 28, 21], [17, 115, 30,  1], [11, 15, 30, 46], [29, 24, 30, 19]],
  [[14, 46, 28, 23], [13, 115, 30,  6], [59, 16, 30,  1], [44, 24, 30,  7]],
  [[12, 47, 28, 26], [12, 121, 30,  7], [22, 15, 30, 41], [39, 24, 30, 14]],
  [[ 6, 47, 28, 34], [ 6, 121, 30, 14], [ 2, 15, 30, 64], [46, 24, 30, 10]],
  [[29, 46, 28, 14], [17, 122, 30,  4], [24, 15, 30, 46], [49, 24, 30, 10]],
  [[13, 46, 28, 32], [ 4, 122, 30, 18], [42, 15, 30, 32], [48, 24, 30, 14]],
  [[40, 47, 28,  7], [20, 117, 30,  4], [10, 15, 30, 67], [43, 24, 30, 22]],
  [[18, 47, 28, 31], [19, 118, 30,  6], [20, 15, 30, 61], [34, 24, 30, 34]]
]

Instance Attribute Summary

Attributes inherited from Matrix

#height, #width

Instance Method Summary collapse

Methods inherited from Matrix

#[], #[]=, #columns, #extract, #rotate, #rows

Constructor Details

#initialize(*args) ⇒ QrMatrix

Returns a new instance of QrMatrix.



3
4
5
6
 
# File 'lib/qrio/qr_matrix.rb', line 3

def initialize(*args)
  super
  @unmasked = false
end

Instance Method Details

#block_count ⇒ Object 



231
232
233
 
# File 'lib/qrio/qr_matrix.rb', line 231

def block_count
  block_structure.inject(0){|sum, (blocks,data,ecc)| sum += blocks }
end

#block_structure ⇒ Object 



235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
 
# File 'lib/qrio/qr_matrix.rb', line 235

def block_structure
  @block_structure ||= begin
    @short_blocks = []
    @long_blocks  = []

    params = block_structure_params.dup

    @short_blocks = params.slice!(0,3)
    structure = [@short_blocks]

    unless params.empty?
      @long_blocks = @short_blocks.dup
      @long_blocks[0] = params[0]
      structure << @long_blocks
    end

    structure
  end
end

#data_or_correction?(x, y) ⇒ Boolean

Returns:

  • (Boolean) 


259
260
261
262
263
 
# File 'lib/qrio/qr_matrix.rb', line 259

def data_or_correction?(x, y)
  ! in_finder_pattern?(x, y)    &&
  ! in_alignment_pattern?(x, y) &&
  ! in_alignment_line?(x, y)
end

#draw_alignment_patterns ⇒ Object 



282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
 
# File 'lib/qrio/qr_matrix.rb', line 282

def draw_alignment_patterns
  rows = ALIGNMENT_CENTERS[version - 1].dup
  cols = rows.dup

  cols.each do |cy|
    rows.each do |cx|
      unless in_finder_pattern?(cx, cy)
        ((cy - 2)...(cy + 2)).each do |y|
          ((cx - 2)...(cx + 2)).each do |x|
            self[x, y] = (cx - x).abs == 2 ||
                         (cy - y).abs == 2 ||
                         (x == cx && y == cy)
          end
        end
      end
    end
  end
end

#ecc_bytes_per_block ⇒ Object 



255
256
257
 
# File 'lib/qrio/qr_matrix.rb', line 255

def ecc_bytes_per_block
  block_structure.first.last
end

#error_correction_level ⇒ Object 



125
126
127
 
# File 'lib/qrio/qr_matrix.rb', line 125

def error_correction_level
  ERROR_CORRECTION_LEVEL[read_format[:error_correction]]
end

#in_alignment_line?(x, y) ⇒ Boolean

Returns:

  • (Boolean) 


301
302
303
 
# File 'lib/qrio/qr_matrix.rb', line 301

def in_alignment_line?(x, y)
  (x == 6) || (y == 6)
end

#in_alignment_pattern?(x, y) ⇒ Boolean

Returns:

  • (Boolean) 


271
272
273
274
275
276
277
278
279
280
 
# File 'lib/qrio/qr_matrix.rb', line 271

def in_alignment_pattern?(x, y)
  return false if version == 1

  alignment_centers = ALIGNMENT_CENTERS[version - 1]

  cy = alignment_centers.detect{|c| (c - y).abs <= 2 }
  cx = alignment_centers.detect{|c| (c - x).abs <= 2 }

  cx && cy && ! in_finder_pattern?(cx, cy)
end

#in_finder_pattern?(x, y) ⇒ Boolean

Returns:

  • (Boolean) 


265
266
267
268
269
 
# File 'lib/qrio/qr_matrix.rb', line 265

def in_finder_pattern?(x, y)
  (x < 9           && y < 9) ||
  (x > (width - 9) && y < 9) ||
  (x < 9           && y > (height - 9))
end

#mask_pattern ⇒ Object 



129
130
131
 
# File 'lib/qrio/qr_matrix.rb', line 129

def mask_pattern
  read_format[:mask_pattern]
end

#mode ⇒ Object 



216
217
218
 
# File 'lib/qrio/qr_matrix.rb', line 216

def mode
  MODE[@mode]
end

#raw_bytes ⇒ Object

raw bytestream, as read from the QR symbol



163
164
165
 
# File 'lib/qrio/qr_matrix.rb', line 163

def raw_bytes
  @raw_bytes ||= read_raw_bytes
end

#text ⇒ Object 



179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
 
# File 'lib/qrio/qr_matrix.rb', line 179

def text
  @text ||= begin
    text = []

    unmask unless @unmasked

    # deinterlace
    @blocks = []

    byte_pointer = 0

    # TODO : handle ragged block sizes
    block_structure.each do |count, data, ecc|
      data.times do |word_index|
        block_count.times do |blk_index|
          @blocks[blk_index] ||= []
          @blocks[blk_index] << raw_bytes[byte_pointer]
          byte_pointer += 1
        end
      end
    end

    @blocks = @blocks.flatten

    set_mode

    character_count = read

    character_count.times do |idx|
      byte = read
      text << byte.chr
    end

    text.join
  end
end

#to_s ⇒ Object 



167
168
169
170
171
172
173
174
175
176
177
 
# File 'lib/qrio/qr_matrix.rb', line 167

def to_s
  str = ""
  rows.each do |row|
    row.each do |m|
      str << (m ? '#' : ' ')
    end
    str << "\n"
  end

  str
end

#unmask ⇒ Object 



137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
 
# File 'lib/qrio/qr_matrix.rb', line 137

def unmask
  p = [
    lambda{|x,y| (x + y) % 2 == 0 },
    lambda{|x,y| x % 2 == 0 },
    lambda{|x,y| y % 3 == 0 },
    lambda{|x,y| (x + y) % 3 == 0 },
    lambda{|x,y| ((x / 2) + (y / 3)) % 2 == 0 },
    lambda{|x,y| prod = x * y;   (prod % 2) + (prod % 3) == 0 },
    lambda{|x,y| prod = x * y; (((prod % 2) + (prod % 3)) % 2) == 0 },
    lambda{|x,y| prod = x * y; sum = x + y; (((prod % 3) + (sum % 2)) % 2) == 0 }
  ][mask_pattern]

  raise "could not load mask pattern #{ mask_pattern }" unless p

  0.upto(height - 1) do |y|
    0.upto(width - 1) do |x|
      if data_or_correction?(x, y)
        self[x, y] = self[x, y] ^ p.call(x, y)
      end
    end
  end

  @unmasked = ! @unmasked
end

#version ⇒ Object 



133
134
135
 
# File 'lib/qrio/qr_matrix.rb', line 133

def version
  (width - 17) / 4
end

#word_size ⇒ Object 



220
221
222
223
224
225
226
227
228
229
 
# File 'lib/qrio/qr_matrix.rb', line 220

def word_size
  @word_size ||= begin
    widths = WORD_WIDTHS[mode]
    version_width = widths.detect{|k,v| k.include? version }

    raise "Could not find word width" if version_width.nil?

    version_width.last
  end
end