|
1
|
|
|
<?php |
|
2
|
|
|
/** |
|
3
|
|
|
* Class ReedSolomonEncoder |
|
4
|
|
|
* |
|
5
|
|
|
* @filesource ReedSolomonEncoder.php |
|
6
|
|
|
* @created 07.01.2021 |
|
7
|
|
|
* @package chillerlan\QRCode\Common |
|
8
|
|
|
* @author smiley <[email protected]> |
|
9
|
|
|
* @copyright 2021 smiley |
|
10
|
|
|
* @license MIT |
|
11
|
|
|
*/ |
|
12
|
|
|
|
|
13
|
|
|
namespace chillerlan\QRCode\Common; |
|
14
|
|
|
|
|
15
|
|
|
use SplFixedArray; |
|
16
|
|
|
|
|
17
|
|
|
use function array_fill, array_merge, count, max; |
|
18
|
|
|
|
|
19
|
|
|
/** |
|
20
|
|
|
* ISO/IEC 18004:2000 Section 8.5 ff |
|
21
|
|
|
* |
|
22
|
|
|
* @see http://www.thonky.com/qr-code-tutorial/error-correction-coding |
|
23
|
|
|
*/ |
|
24
|
|
|
final class ReedSolomonEncoder{ |
|
25
|
|
|
|
|
26
|
|
|
private SplFixedArray $interleavedData; |
|
27
|
|
|
private int $interleavedDataIndex; |
|
28
|
|
|
|
|
29
|
|
|
/** |
|
30
|
|
|
* ECC interleaving |
|
31
|
|
|
* |
|
32
|
|
|
* @return \SplFixedArray<int> |
|
33
|
|
|
*/ |
|
34
|
|
|
public function interleaveEcBytes(BitBuffer $bitBuffer, Version $version, EccLevel $eccLevel):SplFixedArray{ |
|
35
|
|
|
[$numEccCodewords, [[$l1, $b1], [$l2, $b2]]] = $version->getRSBlocks($eccLevel); |
|
36
|
|
|
|
|
37
|
|
|
$rsBlocks = array_fill(0, $l1, [$numEccCodewords + $b1, $b1]); |
|
38
|
|
|
|
|
39
|
|
|
if($l2 > 0){ |
|
40
|
|
|
$rsBlocks = array_merge($rsBlocks, array_fill(0, $l2, [$numEccCodewords + $b2, $b2])); |
|
41
|
|
|
} |
|
42
|
|
|
|
|
43
|
|
|
$bitBufferData = $bitBuffer->getBuffer(); |
|
44
|
|
|
$dataBytes = []; |
|
45
|
|
|
$ecBytes = []; |
|
46
|
|
|
$maxDataBytes = 0; |
|
47
|
|
|
$maxEcBytes = 0; |
|
48
|
|
|
$dataByteOffset = 0; |
|
49
|
|
|
|
|
50
|
|
|
foreach($rsBlocks as $key => $block){ |
|
51
|
|
|
[$rsBlockTotal, $dataByteCount] = $block; |
|
52
|
|
|
|
|
53
|
|
|
$dataBytes[$key] = []; |
|
54
|
|
|
|
|
55
|
|
|
for($i = 0; $i < $dataByteCount; $i++){ |
|
56
|
|
|
$dataBytes[$key][$i] = $bitBufferData[$i + $dataByteOffset] & 0xff; |
|
57
|
|
|
} |
|
58
|
|
|
|
|
59
|
|
|
$ecByteCount = $rsBlockTotal - $dataByteCount; |
|
60
|
|
|
$ecBytes[$key] = $this->generateEcBytes($dataBytes[$key], $ecByteCount); |
|
61
|
|
|
$maxDataBytes = max($maxDataBytes, $dataByteCount); |
|
62
|
|
|
$maxEcBytes = max($maxEcBytes, $ecByteCount); |
|
63
|
|
|
$dataByteOffset += $dataByteCount; |
|
64
|
|
|
} |
|
65
|
|
|
|
|
66
|
|
|
$this->interleavedData = new SplFixedArray($version->getTotalCodewords()); |
|
67
|
|
|
$this->interleavedDataIndex = 0; |
|
68
|
|
|
$numRsBlocks = $l1 + $l2; |
|
69
|
|
|
|
|
70
|
|
|
$this->interleave($dataBytes, $maxDataBytes, $numRsBlocks); |
|
71
|
|
|
$this->interleave($ecBytes, $maxEcBytes, $numRsBlocks); |
|
72
|
|
|
|
|
73
|
|
|
return $this->interleavedData; |
|
74
|
|
|
} |
|
75
|
|
|
|
|
76
|
|
|
/** |
|
77
|
|
|
* |
|
78
|
|
|
*/ |
|
79
|
|
|
private function generateEcBytes(array $dataBytes, int $ecByteCount):array{ |
|
80
|
|
|
$rsPoly = new GenericGFPoly([1]); |
|
81
|
|
|
|
|
82
|
|
|
for($i = 0; $i < $ecByteCount; $i++){ |
|
83
|
|
|
$rsPoly = $rsPoly->multiply(new GenericGFPoly([1, GF256::exp($i)])); |
|
84
|
|
|
} |
|
85
|
|
|
|
|
86
|
|
|
$rsPolyDegree = $rsPoly->getDegree(); |
|
87
|
|
|
|
|
88
|
|
|
$modCoefficients = (new GenericGFPoly($dataBytes, $rsPolyDegree)) |
|
89
|
|
|
->mod($rsPoly) |
|
90
|
|
|
->getCoefficients() |
|
91
|
|
|
; |
|
92
|
|
|
|
|
93
|
|
|
$ecBytes = array_fill(0, $rsPolyDegree, 0); |
|
94
|
|
|
$count = count($modCoefficients) - $rsPolyDegree; |
|
95
|
|
|
|
|
96
|
|
|
foreach($ecBytes as $i => &$val){ |
|
97
|
|
|
$modIndex = $i + $count; |
|
98
|
|
|
$val = $modIndex >= 0 ? $modCoefficients[$modIndex] : 0; |
|
99
|
|
|
} |
|
100
|
|
|
|
|
101
|
|
|
return $ecBytes; |
|
102
|
|
|
} |
|
103
|
|
|
|
|
104
|
|
|
/** |
|
105
|
|
|
* |
|
106
|
|
|
*/ |
|
107
|
|
|
private function interleave(array $byteArray, int $maxBytes, int $numRsBlocks):void{ |
|
108
|
|
|
for($x = 0; $x < $maxBytes; $x++){ |
|
109
|
|
|
for($y = 0; $y < $numRsBlocks; $y++){ |
|
110
|
|
|
if($x < count($byteArray[$y])){ |
|
111
|
|
|
$this->interleavedData[$this->interleavedDataIndex++] = $byteArray[$y][$x]; |
|
112
|
|
|
} |
|
113
|
|
|
} |
|
114
|
|
|
} |
|
115
|
|
|
} |
|
116
|
|
|
|
|
117
|
|
|
} |
|
118
|
|
|
|
chillerlan /
php-qrcode
