mirror of
https://github.com/Merricx/qrazybox.git
synced 2024-11-22 02:52:57 +01:00
1251 lines
38 KiB
JavaScript
1251 lines
38 KiB
JavaScript
/*************************************************************************
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QR Code Decoder (Alternative algorithm)
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Decoding QR Code forcely although it was badly damaged
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And extract valuable information on it
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Ported from Strong-QR-Decoder (sqrd.py) with some modifications
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(https://github.com/waidotto/strong-qr-decoder)
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************************************************************************/
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var result = {message:"",error:[]};
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EXT_ENCODING = [
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"ISO/IEC 8859-1 (Latin-1)",
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"ISO/IEC 8859-1 (Latin-1)",
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"ISO/IEC 8859-1 (Latin-1)",
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"ISO/IEC 8859-1 (Latin-1)",
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"ISO/IEC 8859-2 (Latin-2)",
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"ISO/IEC 8859-3 (Latin-3)",
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"ISO/IEC 8859-4 (Latin-4)",
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"ISO/IEC 8859-5 (Latin/Cyrillic)",
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"ISO/IEC 8859-6 (Latin/Arabic)",
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"ISO/IEC 8859-7 (Latin/Greek)",
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"ISO/IEC 8859-8 (Latin/Hebrew)",
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"ISO/IEC 8859-9 (Latin-5)",
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"ISO/IEC 8859-10 (Latin-6)",
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"ISO/IEC 8859-11 (Latin/Thai)",
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"",
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"ISO/IEC 8859-13 (Latin-7)",
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"ISO/IEC 8859-14 (Latin-8/Celtic)",
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"ISO/IEC 8859-15 (Latin-9)",
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"ISO/IEC 8859-16 (Latin-10)",
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"",
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"Shift JIS",
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"Windows-1250",
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"Windows-1251",
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"Windows-1252",
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"Windows-1256",
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"UTF-16",
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"UTF-8",
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"US-ASCII",
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"Big5",
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"GB18030",
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"EUC-KR"
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]
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function getExtendedEncoding(code){
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if(code > EXT_ENCODING.length){
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return EXT_ENCODING[0];
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} else {
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return EXT_ENCODING[code];
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}
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}
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function hammingDistance(s1, s2){
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if(s1.length != s1.length){
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console.log("[ERROR]: inconsistent string lengths");
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result.error.push("Inconsistent string lengths");
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}
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var r = 0;
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for(var i=0; i < s1.length; i++){
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if(s1[i] != s2[i]){
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r += 1;
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}
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}
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return r;
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}
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function mask(pat, i, j){
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if(pat == 0b0)
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return (i + j) % 2 == 0;
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if(pat == 0b1)
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return i % 2 == 0;
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if(pat == 0b10)
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return j % 3 == 0;
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if(pat == 0b11)
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return (i + j) % 3 == 0;
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if(pat == 0b100)
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return (Math.floor(i / 2) + Math.floor(j / 3)) % 2 == 0;
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if(pat == 0b101)
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return (i * j) % 2 + (i * j) % 3 == 0;
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if(pat == 0b110)
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return ((i * j) % 3 + (i * j)) % 2 == 0;
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if(pat == 0b111)
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return ((i * j) % 3 + (i + j)) % 2 == 0;
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console.log("[ERROR]: Invalid mask pattern");
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}
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function index2Vector(index){
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var index2vector_table = [
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null, 1, 2, 4, 8, 16, 32, 64, 128, 29, 58, 116, 232, 205, 135, 19,
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38, 76, 152, 45, 90, 180, 117, 234, 201, 143, 3, 6, 12, 24, 48, 96,
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192, 157, 39, 78, 156, 37, 74, 148, 53, 106, 212, 181, 119, 238, 193, 159,
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35, 70, 140, 5, 10, 20, 40, 80, 160, 93, 186, 105, 210, 185, 111, 222,
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161, 95, 190, 97, 194, 153, 47, 94, 188, 101, 202, 137, 15, 30, 60, 120,
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240, 253, 231, 211, 187, 107, 214, 177, 127, 254, 225, 223, 163, 91, 182, 113,
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226, 217, 175, 67, 134, 17, 34, 68, 136, 13, 26, 52, 104, 208, 189, 103,
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206, 129, 31, 62, 124, 248, 237, 199, 147, 59, 118, 236, 197, 151, 51, 102,
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204, 133, 23, 46, 92, 184, 109, 218, 169, 79, 158, 33, 66, 132, 21, 42,
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84, 168, 77, 154, 41, 82, 164, 85, 170, 73, 146, 57, 114, 228, 213, 183,
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115, 230, 209, 191, 99, 198, 145, 63, 126, 252, 229, 215, 179, 123, 246, 241,
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255, 227, 219, 171, 75, 150, 49, 98, 196, 149, 55, 110, 220, 165, 87, 174,
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65, 130, 25, 50, 100, 200, 141, 7, 14, 28, 56, 112, 224, 221, 167, 83,
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166, 81, 162, 89, 178, 121, 242, 249, 239, 195, 155, 43, 86, 172, 69, 138,
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9, 18, 36, 72, 144, 61, 122, 244, 245, 247, 243, 251, 235, 203, 139, 11,
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22, 44, 88, 176, 125, 250, 233, 207, 131, 27, 54, 108, 216, 173, 71, 142
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]
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if(index == null)
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return 0b00000000;
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else
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return index2vector_table[(((index % 255) + 255) % 255) + 1];
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}
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function vector2Index(v){
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var vector2index_table = [
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null, 255, 1, 25, 2, 50, 26, 198, 3, 223, 51, 238, 27, 104, 199, 75,
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4, 100, 224, 14, 52, 141, 239, 129, 28, 193, 105, 248, 200, 8, 76, 113,
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5, 138, 101, 47, 225, 36, 15, 33, 53, 147, 142, 218, 240, 18, 130, 69,
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29, 181, 194, 125, 106, 39, 249, 185, 201, 154, 9, 120, 77, 228, 114, 166,
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6, 191, 139, 98, 102, 221, 48, 253, 226, 152, 37, 179, 16, 145, 34, 136,
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54, 208, 148, 206, 143, 150, 219, 189, 241, 210, 19, 92, 131, 56, 70, 64,
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30, 66, 182, 163, 195, 72, 126, 110, 107, 58, 40, 84, 250, 133, 186, 61,
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202, 94, 155, 159, 10, 21, 121, 43, 78, 212, 229, 172, 115, 243, 167, 87,
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7, 112, 192, 247, 140, 128, 99, 13, 103, 74, 222, 237, 49, 197, 254, 24,
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227, 165, 153, 119, 38, 184, 180, 124, 17, 68, 146, 217, 35, 32, 137, 46,
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55, 63, 209, 91, 149, 188, 207, 205, 144, 135, 151, 178, 220, 252, 190, 97,
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242, 86, 211, 171, 20, 42, 93, 158, 132, 60, 57, 83, 71, 109, 65, 162,
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31, 45, 67, 216, 183, 123, 164, 118, 196, 23, 73, 236, 127, 12, 111, 246,
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108, 161, 59, 82, 41, 157, 85, 170, 251, 96, 134, 177, 187, 204, 62, 90,
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203, 89, 95, 176, 156, 169, 160, 81, 11, 245, 22, 235, 122, 117, 44, 215,
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79, 174, 213, 233, 230, 231, 173, 232, 116, 214, 244, 234, 168, 80, 88, 175
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];
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return vector2index_table[v];
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}
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function mulGF256(v1, v2){
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if(v1 == 0b00000000 || v2 == 0b00000000)
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return 0b00000000;
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else
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return index2Vector(vector2Index(v1) + vector2Index(v2));
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}
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function calcSyndrome(RS_block, index){
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var s = 0b00000000;
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//console.log(JSON.stringify(RS_block[0]));
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for(var i=0; i < RS_block.length; i++){
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s ^= mulGF256(RS_block[i], index2Vector(index * i));
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//console.log(i, JSON.stringify(RS_block[i]))//, index2Vector(index * i), mulGF256(RS_block[i], index2Vector(index * i)));
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}
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return s
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}
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function detGF256(A){
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if(A.length != A[0].length){
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console.log("[ERROR]: Not square Matrix");
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}
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var size = A.length;
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if(size == 1)
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return A[0][0];
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for(var i=0; i < size-1; i++){
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if(A[i][i] == 0b00000000)
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continue;
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for(var j=i+1; j < size; j++){
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if(A[j][i] == 0b00000000)
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continue;
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var v = index2Vector(vector2Index(A[j][i]) - vector2Index(A[i][i]));
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//if(v == undefined) console.log(A[j][i], A[i][i], vector2Index(A[j][i]) - vector2Index(A[i][i]));
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for(var k=0; k < size; k++){
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A[j][k] ^= mulGF256(A[i][k], v);
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}
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}
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}
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var s = 0b00000001;
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for(var i=0; i < size; i++){
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s = mulGF256(s, A[i][i]);
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}
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return s;
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}
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function solveSE(A){
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var size = A.length;
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if(size == 0)
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return [];
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for(var i=0; i < size-1; i++){
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if(A[i][i] == 0b00000000)
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continue;
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for(var j=i+1; j < size; j++){
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if(A[j][i] == 0b00000000)
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continue;
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var v = index2Vector(vector2Index(A[j][i]) - vector2Index(A[i][i]));
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for(var k=0; k < size+1; k++){
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A[j][k] ^= mulGF256(A[i][k], v);
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}
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}
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}
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var xs = [];
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var size2 = A[0].length;
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for(var i=0; i < size; i++){
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var x = A[size-(i + 1)][size2-1];
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for(var j=0; j < i; j++){
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x ^= mulGF256(xs[j], A[size-(i + 1)][size2-(2 + j)]);
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}
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if(A[size-(i + 1)][size2-(2 - i)] == 0b00000000){
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console.log("[ERROR]: Error correction failed");
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result.error.push("Error correction failed");
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}
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x = mulGF256(x, index2Vector(-vector2Index(A[size-(i + 1)][size2-(2 + i)])));
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xs.push(x);
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}
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return xs //!IMPORTANT;
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}
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function calcSigma(sigmas, index){
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var s = 0b00000000;
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var len = sigmas.length;
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for(var i=0; i < sigmas.length; i++){
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s ^= mulGF256(sigmas[len-(1 + i)], index2Vector(index * i));
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}
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s ^= index2Vector(index * sigmas.length);
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return s;
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}
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function getDataModule(data){
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var width = data.length;
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var version = (width - 21) / 4 + 1;
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var alignment = alignment_pattern_array[version-1];
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var is_data_module = [];
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for(var x=0; x < width; x++){
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var t = [];
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for(var y=0; y < width; y++){
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if((x <= 8 && y <= 8) || (width - 8 <= x && y <= 8) || (x <= 8 && width - 8 <= y) || x == 6 || y == 6)
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t.push(false);
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else
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t.push(true);
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}
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is_data_module.push(t);
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}
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for(var x=0; x < alignment.length; x++){
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for(var y=0; y < alignment.length; y++){
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if(!((alignment[x] < 9 && alignment[y] < 9) || (width - 10 < alignment[x] && alignment[y] < 9) || (alignment[x] < 9 && width - 10 < alignment[y]))){
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for(var i=-2; i < -2+5; i++){
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for(var j=-2; j < -2+5; j++){
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is_data_module[alignment[x] + i][alignment[y] + j] = false;
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}
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}
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}
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}
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}
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if(version >= 7){
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for(var i=0; i < 6; i++){
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for(var j=0; j < 3; j++){
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is_data_module[i][(width)-11 + j] = false
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}
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}
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for(var j=0; j < 6; j++){
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for(var i=0; i < 3; i++){
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is_data_module[(width)-11 + i][j] = false
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}
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}
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}
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return is_data_module;
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}
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function getFormatInfo(data){
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var width = data.length;
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var format_mask = "101010000010010";
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var format_info = "";
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var format_info_unmask = "";
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for(var i=0; i < 15; i++){
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if(i <= 5){
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if(data[i][8] == 1)
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format_info += "1";
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else if(data[i][8] == 0)
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format_info += "0";
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else if(data[i][8] == -1)
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format_info += "?";
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} else if(i == 6){
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if(data[i+1][8] == 1)
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format_info += "1";
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else if(data[i+1][8] == 0)
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format_info += "0";
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else if(data[i+1][8] == -1)
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format_info += "?";
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} else {
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if(data[width-8+i-7][8] == 1)
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format_info += "1";
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else if(data[width-8+i-7][8] == 0)
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format_info += "0";
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else if(data[width-8+i-7][8] == -1)
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format_info += "?";
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}
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}
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format_info = format_info.split("").reverse();
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for(var i=0; i < format_info.length; i++){
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var xored = parseInt(format_info[i]) ^ parseInt(format_mask.charAt(i));
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format_info_unmask += xored;
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}
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var error_correction_level = parseInt(format_info_unmask.substring(0, 2), 2);
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var mask_pattern = parseInt(format_info_unmask.substring(2, 5), 2);
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return {ecc:error_correction_level, mask:mask_pattern};
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}
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function maskData(data_array, mask_pattern){
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var width = data_array.length;
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var data = JSON.parse(JSON.stringify(data_array));
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var is_data_module = getDataModule(data);
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for(var x=0; x < width; x++){
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for(var y=0; y < width; y++){
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if(is_data_module[x][y] && mask(mask_pattern, x, y)){
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if(data[x][y] == 0)
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data[x][y] = 1;
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else if(data[x][y] == 1)
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data[x][y] = 0;
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}
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}
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}
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return data;
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}
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function recoverPaddingBits(data_array){
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var width = data_array.length;
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var version = (width - 21) / 4 + 1;
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var format_info = getFormatInfo(data_array);
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var error_correction_level = format_info.ecc;
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var mask_pattern = format_info.mask;
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var is_data_module = getDataModule(data_array);
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var data = maskData(data_array, mask_pattern);
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var total_codewords = data_code_num_table[version - 1][error_correction_level] * 8;
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var pad_byte = ["11101100","00010001"];
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var blocks = [];
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var block = "";
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count = 0;
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var x = width - 1;
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var y = width - 1;
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while(true){
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if(x < 0 || y < 0)
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break;
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if(is_data_module[x][y]){
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if(data[x][y] == -1)
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block += '?';
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else
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block += data[x][y];
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count += 1;
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if(count == 8){
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blocks.push(block);
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block = "";
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count = 0;
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}
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}
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if(y < 7) tx = y; else tx = y - 1;
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if(tx % 2 == 1)
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y -= 1;
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else {
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if(Math.floor(tx / 2) % 2 == 1){
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if(x == 0)
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y -= 1;
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else {
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x -= 1;
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y += 1;
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}
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}
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else {
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if(x == width - 1){
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if(Math.floor(tx / 2) == 3) y -= 1;
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y -= 1;
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} else {
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x += 1;
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y += 1;
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}
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}
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}
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}
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|
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var block_num = RS_block_num_table[version - 1][error_correction_level];
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var offset = data_code_num_table[version - 1][error_correction_level];
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var data_blocks = "";
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console.log(JSON.stringify(blocks));
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for(var i=0; i < block_num; i++){
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var t = [];
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for(var j=0; j < Math.floor(offset/block_num); j++){
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t.push(blocks[j * block_num + i]);
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}
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if(offset % block_num != 0){
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var remain = offset % block_num;
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if((block_num - remain) <= i){
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t.push(blocks[Math.floor(offset / block_num) * block_num + (i - (block_num - remain))]);
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}
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}
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data_blocks += t.join("");
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}
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var data_bits = data_blocks;
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|
var original_data_bits = "";
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|
var first = true;
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|
|
while(data_bits.length != 0){
|
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var encoding_mode = data_bits.substring(0,4);
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|
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if(encoding_mode == "0001"){
|
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if(data_bits.substring(4,14).search(/\?/g) != -1)
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return "ERROR: Unknown Character Count Indicator";
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|
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var character_count = parseInt(data_bits.substring(4,14), 2);
|
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if(character_count % 3 == 0){
|
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var offset = (character_count/3)*10;
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} else if(character_count % 3 == 1) {
|
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var offset = ((character_count-2)/3)*10;
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offset += 7;
|
|
} else {
|
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var offset = ((character_count-1)/3)*10;
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offset += 4;
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}
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offset += 14;
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|
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} else if(encoding_mode == "0010"){
|
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if(data_bits.substring(4,13).search(/\?/g) != -1)
|
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return "ERROR: Unknown Character Count Indicator";
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|
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var character_count = parseInt(data_bits.substring(4,13), 2);
|
|
if(character_count % 2 == 0){
|
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var offset = (character_count/2)*11;
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} else {
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var offset = ((character_count-1)/2)*11;
|
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offset += 6;
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}
|
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offset += 13;
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} else if(encoding_mode == "0100"){
|
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if(data_bits.substring(4,12).search(/\?/g) != -1)
|
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return "ERROR: Unknown Character Count Indicator";
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|
|
var character_count = parseInt(data_bits.substring(4,12), 2);
|
|
var offset = character_count*8;
|
|
offset += 12;
|
|
|
|
} else if(encoding_mode == "1000"){
|
|
if(data_bits.substring(4,12).search(/\?/g) != -1)
|
|
return "ERROR: Unknown Character Count Indicator";
|
|
|
|
var character_count = parseInt(data_bits.substring(4,12), 2);
|
|
var offset = character_count*13;
|
|
offset += 12;
|
|
|
|
} else if(encoding_mode == "0111"){
|
|
|
|
if(data_bits.substring(4,5) == "0"){
|
|
offset += 12;
|
|
} else if(data_bits.substring(4,6) == "10"){
|
|
offset += 20;
|
|
} else if(data_bits.substring(4,7) == "110"){
|
|
offset += 28;
|
|
} else {
|
|
return "ERROR: Invalid ECI Assignment Number";
|
|
}
|
|
|
|
|
|
} else if(encoding_mode == "0000"){
|
|
break;
|
|
} else {
|
|
if(first)
|
|
return "ERROR: Unknown Encoding Mode";
|
|
else
|
|
break;
|
|
}
|
|
original_data_bits += data_bits.substring(0,offset);
|
|
data_bits = data_bits.substring(offset);
|
|
first = false;
|
|
}
|
|
|
|
var target_bits = data_bits;
|
|
if(target_bits == "" || target_bits.length < 8){
|
|
console.log(target_bits);
|
|
return "ERROR: Current QR code didn't use padding bits";
|
|
}
|
|
|
|
var result = "";
|
|
|
|
var starting_bits = 8-((offset) % 8);
|
|
if(starting_bits < 4)
|
|
starting_bits = 8+starting_bits;
|
|
console.log(offset, starting_bits, target_bits);
|
|
|
|
target_bits = target_bits.substring(starting_bits);
|
|
|
|
for(var i=0; i < starting_bits; i++){
|
|
result += "0";
|
|
}
|
|
|
|
var alternate = 0;
|
|
while(target_bits.length != 0){
|
|
result += pad_byte[alternate];
|
|
alternate ^= 1;
|
|
target_bits = target_bits.substring(8);
|
|
}
|
|
|
|
blocks = (original_data_bits + result).match(/.{1,8}/g);
|
|
interleaved_blocks = "";
|
|
|
|
var block_num = RS_block_num_table[version - 1][error_correction_level];
|
|
var offset = data_code_num_table[version - 1][error_correction_level];
|
|
|
|
for(var i=0; i < Math.floor(offset/block_num); i++){
|
|
var t = [];
|
|
for(var j=0; j < block_num; j++){
|
|
t.push(blocks[j * Math.floor(offset/block_num) + i]);
|
|
}
|
|
interleaved_blocks += t.join("");
|
|
}
|
|
console.log(interleaved_blocks.match(/.{1,8}/g));
|
|
blocks = interleaved_blocks;
|
|
|
|
x = width-1;
|
|
y = width-1;
|
|
var index = 0;
|
|
var result_array = data;
|
|
while(true){
|
|
if(x < 0 || y < 0 || blocks.charAt(index) == "")
|
|
break;
|
|
if(is_data_module[x][y]){
|
|
if(blocks.charAt(index) == "?")
|
|
result_array[x][y] = -1;
|
|
else
|
|
result_array[x][y] = parseInt(blocks.charAt(index));
|
|
index++;
|
|
}
|
|
if(y < 7) tx = y; else tx = y - 1;
|
|
if(tx % 2 == 1)
|
|
y -= 1;
|
|
else {
|
|
if(Math.floor(tx / 2) % 2 == 1){
|
|
if(x == 0)
|
|
y -= 1;
|
|
else {
|
|
x -= 1;
|
|
y += 1;
|
|
}
|
|
}
|
|
else {
|
|
if(x == width - 1){
|
|
if(Math.floor(tx / 2) == 3) y -= 1;
|
|
y -= 1;
|
|
} else {
|
|
x += 1;
|
|
y += 1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
result_array = maskData(result_array, mask_pattern);
|
|
|
|
|
|
|
|
return {result_array:result_array, after:result, before:data_bits};
|
|
}
|
|
|
|
function QRDecode(data){
|
|
|
|
result = {message:"",error:[],error_count:0,ecc:0,mask_pattern:0,erasure_count:0,data_module_count:0,module_order:[]};
|
|
|
|
var width = data.length;
|
|
var version = (width - 21) / 4 + 1;
|
|
|
|
var is_data_module = getDataModule(data);
|
|
|
|
var format_info = getFormatInfo(data);
|
|
|
|
var error_correction_level = format_info.ecc;
|
|
var mask_pattern = format_info.mask;
|
|
console.log("Error Correction Level : ", error_correction_level, "Mask Pattern : ", mask_pattern);
|
|
|
|
if(error_correction_level == 0b0000)
|
|
result.ecc = "M";
|
|
else if(error_correction_level == 0b0001)
|
|
result.ecc = "L";
|
|
else if(error_correction_level == 0b0010)
|
|
result.ecc = "H";
|
|
else if(error_correction_level == 0b0011)
|
|
result.ecc = "Q";
|
|
result.mask_pattern = mask_pattern;
|
|
|
|
data = maskData(data, mask_pattern);
|
|
|
|
var blocks = [];
|
|
var block = "";
|
|
count = 0;
|
|
var x = width - 1;
|
|
var y = width - 1;
|
|
while(true){
|
|
if(x < 0 || y < 0)
|
|
break;
|
|
if(is_data_module[x][y]){
|
|
if(data[x][y] == -1)
|
|
block += '?';
|
|
else
|
|
block += data[x][y];
|
|
count += 1;
|
|
if(count == 8){
|
|
blocks.push(block);
|
|
block = "";
|
|
count = 0;
|
|
}
|
|
result.module_order.push(x+"-"+y);
|
|
}
|
|
if(y < 7) tx = y; else tx = y - 1;
|
|
if(tx % 2 == 1)
|
|
y -= 1;
|
|
else {
|
|
if(Math.floor(tx / 2) % 2 == 1){
|
|
if(x == 0)
|
|
y -= 1;
|
|
else {
|
|
x -= 1;
|
|
y += 1;
|
|
}
|
|
}
|
|
else {
|
|
if(x == width - 1){
|
|
if(Math.floor(tx / 2) == 3) y -= 1;
|
|
y -= 1;
|
|
} else {
|
|
x += 1;
|
|
y += 1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
for(var i=0; i < blocks.length; i++){
|
|
for(var j=0; j < blocks.length; j++){
|
|
if(blocks[i].charAt(j) == '?'){
|
|
result.erasure_count += 1;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
result.data_blocks = JSON.stringify(blocks);
|
|
result.data_module_count = blocks.length;
|
|
console.log(JSON.stringify(blocks));
|
|
|
|
var RS_blocks = [];
|
|
var block_num = RS_block_num_table[version - 1][error_correction_level];
|
|
var offset = data_code_num_table[version - 1][error_correction_level];
|
|
|
|
for(var i=0; i < block_num; i++){
|
|
var t = [];
|
|
for(var j=0; j < Math.floor(offset/block_num); j++){
|
|
t.push(blocks[j * block_num + i]);
|
|
}
|
|
if(offset % block_num != 0){
|
|
var remain = offset % block_num;
|
|
if((block_num - remain) <= i)
|
|
t.push(blocks[Math.floor(offset / block_num) * block_num + (i - (block_num - remain))])
|
|
}
|
|
for(var j=0; j < Math.floor((blocks.length - offset) / block_num); j++){
|
|
t.push(blocks[offset + j * block_num + i]);
|
|
}
|
|
t = t.reverse();
|
|
RS_blocks.push(t);
|
|
}
|
|
console.log("RS Blocks : ",JSON.stringify(RS_blocks));
|
|
|
|
var unknown_code_nums = [];
|
|
for(var i=0; i < RS_blocks.length; i++){
|
|
var s = 0;
|
|
for(var j=0; j < RS_blocks[i].length; j++){
|
|
if(RS_blocks[i][j].search(/\?/g) > -1)
|
|
s += 1;
|
|
}
|
|
unknown_code_nums.push(s);
|
|
}
|
|
|
|
for(var i=0; i < block_num; i++){
|
|
for(var j=0; j < RS_blocks[i].length; j++){
|
|
if(RS_blocks[i][j].search(/\?/g) > -1)
|
|
RS_blocks[i][j] = 0;
|
|
else
|
|
RS_blocks[i][j] = parseInt(RS_blocks[i][j], 2)
|
|
}
|
|
}
|
|
console.log("RS Blocks : ",JSON.stringify(RS_blocks));
|
|
|
|
var limit_error_correction_num;
|
|
|
|
if(version == 1){
|
|
if(error_correction_level == 0b01)
|
|
limit_error_correction_num = 2;
|
|
else if(error_correction_level == 0b00)
|
|
limit_error_correction_num = 4;
|
|
else if(error_correction_level == 0b11)
|
|
limit_error_correction_num = 6;
|
|
else if(error_correction_level == 0b10)
|
|
limit_error_correction_num = 8;
|
|
} else if(version == 2 && error_correction_level == 0b01){
|
|
limit_error_correction_num = 4;
|
|
} else if(version == 3 && error_correction_level == 0b01){
|
|
limit_error_correction_num = 7;
|
|
} else {
|
|
limit_error_correction_num = Math.floor((blocks.length - offset) / block_num) / 2;
|
|
}
|
|
//console.log(limit_error_correction_num);
|
|
|
|
result.rs_block = [];
|
|
result.syndrome = [];
|
|
result.error_count = [];
|
|
result.coeff_error = [];
|
|
result.error_position = [];
|
|
result.error_magnitude = [];
|
|
much_missing_bits = false;
|
|
//Error correction here!!!!!!!!!!!
|
|
for(var i=0; i < block_num; i++){
|
|
var t = Array.prototype.slice.call(RS_blocks[i]).reverse();
|
|
result.rs_block.push(JSON.stringify(t));
|
|
if(limit_error_correction_num < unknown_code_nums[i]){
|
|
much_missing_bits = true;
|
|
continue;
|
|
}
|
|
var syndrome_length = Math.floor((blocks.length - offset) / block_num);
|
|
|
|
var syndromes = [];
|
|
for(var j=0; j < syndrome_length; j++){
|
|
syndromes.push(calcSyndrome(RS_blocks[i], j))
|
|
}
|
|
result.syndrome.push(JSON.stringify(syndromes));
|
|
|
|
var no_error = true;
|
|
for(var j=0; j < syndrome_length; j++){
|
|
if(syndromes[j] != 0b00000000)
|
|
no_error = false;
|
|
}
|
|
console.log("Syndromes : ",JSON.stringify(syndromes));
|
|
if(no_error)
|
|
continue;
|
|
|
|
var A;
|
|
for(var size=Math.floor(syndrome_length / 2) - 1; size > 0; size--){
|
|
A = [];
|
|
for(var j=0; j < size; j++){
|
|
var row = [];
|
|
for(var k=0; k < size; k++){
|
|
row.push(syndromes[j+k]);
|
|
}
|
|
A.push(row);
|
|
}
|
|
var det = detGF256(A);
|
|
if(det != 0b00000000){
|
|
break;
|
|
}
|
|
}
|
|
//console.log(JSON.stringify(A));
|
|
|
|
var num_error = A.length; console.log("Number of Errors : ",num_error);
|
|
result.error_count.push(num_error);
|
|
A = [];
|
|
for(var j=0; j < num_error; j++){
|
|
var row = [];
|
|
for(var k=0; k < num_error+1; k++){
|
|
row.push(syndromes[j+k]);
|
|
}
|
|
A.push(row);
|
|
}
|
|
var sigmas = solveSE(Array.prototype.slice.call(A));
|
|
result.coeff_error.push(JSON.stringify(sigmas));
|
|
|
|
var indexes = [];
|
|
for(var j=0; j < RS_blocks[i].length; j++){
|
|
var s = calcSigma(sigmas, j);
|
|
if(s == 0b00000000)
|
|
indexes.push(j);
|
|
}
|
|
console.log("Error positions : ",indexes);
|
|
result.error_position.push(JSON.stringify(indexes));
|
|
|
|
A = [];
|
|
for(var j=0; j < indexes.length; j++){
|
|
var row = [];
|
|
for(var k=0; k < indexes.length; k++){
|
|
row.push(index2Vector(j * indexes[k]));
|
|
}
|
|
row.push(syndromes[j]);
|
|
A.push(row);
|
|
}
|
|
|
|
var errors = solveSE(Array.prototype.slice.call(A)).reverse();
|
|
var errors_str = "";
|
|
for(var j=0; j < errors.length; j++){
|
|
errors_str += errors[j].toString(2) + " ";
|
|
}
|
|
result.error_magnitude.push(errors_str);
|
|
|
|
for(var j=0; j < indexes.length; j++){
|
|
RS_blocks[i][indexes[j]] ^= errors[j];
|
|
}
|
|
console.log("RS Blocks after error correction : ", JSON.stringify(RS_blocks));
|
|
}
|
|
|
|
if(much_missing_bits) result.error.push("Too much missing bits");
|
|
|
|
for(var i=0; i < RS_blocks.length; i++){
|
|
RS_blocks[i] = RS_blocks[i].reverse();
|
|
}
|
|
|
|
var data_bytes = [];
|
|
for(var i=0; i < RS_blocks.length; i++){
|
|
if((block_num - (offset % block_num)) <= i)
|
|
var val = 1;
|
|
else
|
|
var val = 0;
|
|
var limit = Math.floor(offset / block_num) + val;
|
|
for(var j=0; j < limit;j++){
|
|
data_bytes.push(RS_blocks[i][j]);
|
|
}
|
|
}
|
|
console.log("Data bytes : ",JSON.stringify(data_bytes));
|
|
|
|
var data_bits = "";
|
|
for(var i=0; i < data_bytes.length; i++){
|
|
var pad = "00000000";
|
|
var text = data_bytes[i].toString(2);
|
|
var remain = (pad+text).length - 8;
|
|
text = (pad + text).slice(remain);
|
|
data_bits += text;
|
|
}
|
|
console.log("Data bits :",data_bits);
|
|
result.data_bits = data_bits;
|
|
|
|
var data = [];
|
|
result.data_bits_count = 0;
|
|
result.data_bits_block = [];
|
|
result.mode = [];
|
|
result.count = [];
|
|
result.decoded = [];
|
|
while(data_bits.length != 0){
|
|
mode = parseInt(data_bits.substring(0,4), 2);
|
|
var temp_data = "["+data_bits.substring(0,4)+"] ";
|
|
data_bits = data_bits.substring(4);
|
|
|
|
if(mode == 0b0001){
|
|
var length_indicator = 10;
|
|
if ( version > 9 && version <= 26 ){
|
|
length_indicator = 12;
|
|
} else if ( version > 26 ){
|
|
length_indicator = 14;
|
|
}
|
|
|
|
var num = "";
|
|
length = parseInt(data_bits.substring(0, length_indicator), 2);
|
|
temp_data += "["+data_bits.substring(0, length_indicator)+"] [";
|
|
data_bits = data_bits.substring(length_indicator);
|
|
console.log("Data length : ",length);
|
|
console.log("Data sequence : ",data_bits);
|
|
|
|
result.mode.push("Numeric Mode (0001)");
|
|
result.count.push(length);
|
|
|
|
for(var i=0; i < Math.floor((length + 2) / 3); i++){
|
|
if(i == Math.floor((length + 2) / 3) - 1){
|
|
if(length % 3 == 0){
|
|
num += parseInt(data_bits.substring(0,10), 2);
|
|
temp_data += data_bits.substring(0,10);
|
|
data_bits = data_bits.substring(10);
|
|
} else if(length % 3 == 1){
|
|
num += parseInt(data_bits.substring(0,4), 2);
|
|
temp_data += data_bits.substring(0,4);
|
|
data_bits = data_bits.substring(4);
|
|
} else {
|
|
num += parseInt(data_bits.substring(0,7), 2);
|
|
temp_data += data_bits.substring(0,7);
|
|
data_bits = data_bits.substring(7);
|
|
}
|
|
} else {
|
|
num += parseInt(data_bits.substring(0,10), 2);
|
|
temp_data += data_bits.substring(0,10);
|
|
data_bits = data_bits.substring(10);
|
|
}
|
|
}
|
|
temp_data += "]";
|
|
result.decoded.push(num);
|
|
|
|
data.push.apply(data, num.split(""));
|
|
|
|
} else if(mode == 0b0010){
|
|
var length_indicator = 9;
|
|
if ( version > 9 && version <= 26 ){
|
|
length_indicator = 11;
|
|
} else if ( version > 26 ){
|
|
length_indicator = 13;
|
|
}
|
|
|
|
var current_data = "";
|
|
length = parseInt(data_bits.substring(0, length_indicator), 2);
|
|
temp_data += "["+data_bits.substring(0, length_indicator)+"] [";
|
|
data_bits = data_bits.substring(length_indicator);
|
|
console.log("Data length : ",length);
|
|
console.log("Data sequence : ",data_bits);
|
|
|
|
result.mode.push("Alphanumeric Mode (0010)");
|
|
result.count.push(length);
|
|
|
|
for(var i=0; i < Math.floor((length + 1) / 2); i++){
|
|
if(i == Math.floor((length + 1) / 2) - 1){
|
|
if(length % 2 == 0){
|
|
num = (parseInt(data_bits.substring(0,11), 2));
|
|
temp_data += data_bits.substring(0,11);
|
|
data_bits = data_bits.substring(11);
|
|
data.push(alphanumeric_table[Math.floor(num / 45)]);
|
|
data.push(alphanumeric_table[num % 45]);
|
|
current_data += alphanumeric_table[Math.floor(num / 45)];
|
|
current_data += alphanumeric_table[Math.floor(num % 45)];
|
|
} else {
|
|
num = (parseInt(data_bits.substring(0,6), 2));
|
|
temp_data += data_bits.substring(0,6);
|
|
data_bits = data_bits.substring(6);
|
|
data.push(alphanumeric_table[num]);
|
|
current_data += alphanumeric_table[num];
|
|
}
|
|
} else {
|
|
num = (parseInt(data_bits.substring(0,11), 2));
|
|
temp_data += data_bits.substring(0,11);
|
|
data_bits = data_bits.substring(11);
|
|
data.push(alphanumeric_table[Math.floor(num / 45)]);
|
|
data.push(alphanumeric_table[num % 45]);
|
|
current_data += alphanumeric_table[Math.floor(num / 45)];
|
|
current_data += alphanumeric_table[Math.floor(num % 45)];
|
|
}
|
|
}
|
|
temp_data += "]";
|
|
result.decoded.push(current_data);
|
|
|
|
} else if(mode == 0b0100){
|
|
var length_indicator = 8;
|
|
if ( version > 9 ){
|
|
length_indicator = 16;
|
|
}
|
|
|
|
var current_data = "";
|
|
length = parseInt(data_bits.substring(0, length_indicator), 2);
|
|
temp_data += "["+data_bits.substring(0, length_indicator)+"] [";
|
|
data_bits = data_bits.substring(length_indicator);
|
|
console.log("Data length : ",length);
|
|
console.log("Data sequence : ",data_bits);
|
|
|
|
result.mode.push("8-bit Mode (0100)");
|
|
result.count.push(length);
|
|
|
|
for(var i=0; i < length; i++){
|
|
data.push(String.fromCharCode(parseInt(data_bits.substring(0,8), 2)));
|
|
temp_data += data_bits.substring(0,11);
|
|
current_data += String.fromCharCode(parseInt(data_bits.substring(0,8), 2));
|
|
data_bits = data_bits.substring(8);
|
|
}
|
|
temp_data += "]";
|
|
result.decoded.push(current_data);
|
|
} else if(mode == 0b0000){
|
|
break;
|
|
} else if(mode == 0b1000){
|
|
//TODO: Kanji mode
|
|
break;
|
|
} else if(mode == 0b0111){
|
|
// ECI Mode
|
|
result.mode.push("ECI Mode (0111)");
|
|
|
|
if(data_bits.substring(0,1) == "0"){
|
|
|
|
temp_data += "["+data_bits.substring(0, 8)+"]";
|
|
special_encoding = parseInt(data_bits.substring(0,8), 2);
|
|
data_bits = data_bits.substring(8);
|
|
|
|
result.count.push(special_encoding);
|
|
result.decoded.push(getExtendedEncoding(special_encoding));
|
|
|
|
} else if(data_bits.substring(0,2) == "10"){
|
|
|
|
temp_data += "["+data_bits.substring(0, 16)+"]";
|
|
special_encoding = parseInt(data_bits.substring(0,16), 2);
|
|
data_bits = data_bits.substring(16);
|
|
|
|
result.count.push(special_encoding);
|
|
result.decoded.push(getExtendedEncoding(special_encoding));
|
|
} else if(data_bits.substring(0,3) == "110"){
|
|
|
|
temp_data += "["+data_bits.substring(0, 24)+"]";
|
|
special_encoding = parseInt(data_bits.substring(0,24), 2);
|
|
data_bits = data_bits.substring(24);
|
|
|
|
result.count.push(special_encoding);
|
|
result.decoded.push(getExtendedEncoding(special_encoding));
|
|
} else {
|
|
console.log("[ERROR]: Invalid ECI Assignment Number");
|
|
result.error.push("[ERROR]: Invalid ECI Assignment Number");
|
|
break;
|
|
}
|
|
} else {
|
|
console.log("[ERROR]: Invalid Encoding mode", mode);
|
|
result.error.push("Invalid Encoding mode");
|
|
break;
|
|
}
|
|
result.data_bits_block.push(temp_data);
|
|
result.data_bits_count += 1;
|
|
}
|
|
console.log(data.join(""));
|
|
|
|
result.message = data.join("");
|
|
|
|
return result;
|
|
}
|
|
|
|
function readDataBlock(data){
|
|
|
|
data = JSON.parse(JSON.stringify(data));
|
|
|
|
var width = data.length;
|
|
var version = (width - 21) / 4 + 1;
|
|
var is_data_module = getDataModule(data);
|
|
var format_info = getFormatInfo(data);
|
|
var error_correction_level = format_info.ecc;
|
|
var mask_pattern = format_info.mask;
|
|
data = maskData(data, mask_pattern);
|
|
|
|
var module_order = [];
|
|
|
|
var blocks = [];
|
|
var block = "";
|
|
count = 0;
|
|
var x = width - 1;
|
|
var y = width - 1;
|
|
while(true){
|
|
if(x < 0 || y < 0)
|
|
break;
|
|
if(is_data_module[x][y]){
|
|
if(data[x][y] == -1)
|
|
block += '?';
|
|
else
|
|
block += data[x][y];
|
|
count += 1;
|
|
if(count == 8){
|
|
blocks.push(block);
|
|
block = "";
|
|
count = 0;
|
|
}
|
|
module_order.push(x+"-"+y);
|
|
}
|
|
if(y < 7) tx = y; else tx = y - 1;
|
|
if(tx % 2 == 1)
|
|
y -= 1;
|
|
else {
|
|
if(Math.floor(tx / 2) % 2 == 1){
|
|
if(x == 0)
|
|
y -= 1;
|
|
else {
|
|
x -= 1;
|
|
y += 1;
|
|
}
|
|
}
|
|
else {
|
|
if(x == width - 1){
|
|
if(Math.floor(tx / 2) == 3) y -= 1;
|
|
y -= 1;
|
|
} else {
|
|
x += 1;
|
|
y += 1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*var RS_blocks = "";
|
|
var block_num = RS_block_num_table[version - 1][error_correction_level];
|
|
var offset = data_code_num_table[version - 1][error_correction_level];
|
|
|
|
for(var i=0; i < block_num; i++){
|
|
var t = [];
|
|
for(var j=0; j < Math.floor(offset/block_num); j++){
|
|
t.push(blocks[j * block_num + i]);
|
|
}
|
|
if(offset % block_num != 0){
|
|
var remain = offset % block_num;
|
|
if((block_num - remain) <= i)
|
|
t.push(blocks[Math.floor(offset / block_num) * block_num + (i - (block_num - remain))])
|
|
}
|
|
for(var j=0; j < Math.floor((blocks.length - offset) / block_num); j++){
|
|
t.push(blocks[offset + j * block_num + i]);
|
|
}
|
|
|
|
RS_blocks += t.join("");
|
|
}
|
|
|
|
blocks = RS_blocks;*/
|
|
|
|
return {blocks:blocks.join(""),module_order:module_order};
|
|
}
|
|
|
|
function readDataBits(data_bits){
|
|
|
|
var data = [];
|
|
while(data_bits.length != 0){
|
|
mode = parseInt(data_bits.substring(0,4), 2);
|
|
var temp_data = "["+data_bits.substring(0,4)+"] ";
|
|
data_bits = data_bits.substring(4);
|
|
|
|
if(mode == 0b0001){
|
|
var length_indicator = 10;
|
|
var num = "";
|
|
length = parseInt(data_bits.substring(0, length_indicator), 2);
|
|
temp_data += "["+data_bits.substring(0, length_indicator)+"] [";
|
|
data_bits = data_bits.substring(length_indicator);
|
|
console.log("Data length : ",length);
|
|
console.log("Data sequence : ",data_bits);
|
|
|
|
for(var i=0; i < Math.floor((length + 2) / 3); i++){
|
|
if(i == Math.floor((length + 2) / 3) - 1){
|
|
if(length % 3 == 0){
|
|
num += parseInt(data_bits.substring(0,10), 2);
|
|
temp_data += data_bits.substring(0,10);
|
|
data_bits = data_bits.substring(10);
|
|
} else if(length % 3 == 1){
|
|
num += parseInt(data_bits.substring(0,4), 2);
|
|
temp_data += data_bits.substring(0,4);
|
|
data_bits = data_bits.substring(4);
|
|
} else {
|
|
num += parseInt(data_bits.substring(0,7), 2);
|
|
temp_data += data_bits.substring(0,7);
|
|
data_bits = data_bits.substring(7);
|
|
}
|
|
} else {
|
|
num += parseInt(data_bits.substring(0,10), 2);
|
|
temp_data += data_bits.substring(0,10);
|
|
data_bits = data_bits.substring(10);
|
|
}
|
|
}
|
|
temp_data += "]";
|
|
result.decoded.push(num);
|
|
|
|
data.push.apply(data, num.split(""));
|
|
|
|
} else if(mode == 0b0010){
|
|
var length_indicator = 9;
|
|
var current_data = "";
|
|
length = parseInt(data_bits.substring(0, length_indicator), 2);
|
|
temp_data += "["+data_bits.substring(0, length_indicator)+"] [";
|
|
data_bits = data_bits.substring(length_indicator);
|
|
console.log("Data length : ",length);
|
|
console.log("Data sequence : ",data_bits);
|
|
|
|
for(var i=0; i < Math.floor((length + 1) / 2); i++){
|
|
if(i == Math.floor((length + 1) / 2) - 1){
|
|
if(length % 2 == 0){
|
|
num = (parseInt(data_bits.substring(0,11), 2));
|
|
temp_data += data_bits.substring(0,11);
|
|
data_bits = data_bits.substring(11);
|
|
data.push(alphanumeric_table[Math.floor(num / 45)]);
|
|
data.push(alphanumeric_table[num % 45]);
|
|
current_data += alphanumeric_table[Math.floor(num / 45)];
|
|
current_data += alphanumeric_table[Math.floor(num % 45)];
|
|
} else {
|
|
num = (parseInt(data_bits.substring(0,6), 2));
|
|
temp_data += data_bits.substring(0,6);
|
|
data_bits = data_bits.substring(6);
|
|
data.push(alphanumeric_table[num]);
|
|
current_data += alphanumeric_table[num];
|
|
}
|
|
} else {
|
|
num = (parseInt(data_bits.substring(0,11), 2));
|
|
temp_data += data_bits.substring(0,11);
|
|
data_bits = data_bits.substring(11);
|
|
data.push(alphanumeric_table[Math.floor(num / 45)]);
|
|
data.push(alphanumeric_table[num % 45]);
|
|
current_data += alphanumeric_table[Math.floor(num / 45)];
|
|
current_data += alphanumeric_table[Math.floor(num % 45)];
|
|
}
|
|
}
|
|
temp_data += "]";
|
|
|
|
} else if(mode == 0b0100){
|
|
var length_indicator = 8;
|
|
var current_data = "";
|
|
length = parseInt(data_bits.substring(0, length_indicator), 2);
|
|
temp_data += "["+data_bits.substring(0, length_indicator)+"] [";
|
|
data_bits = data_bits.substring(length_indicator);
|
|
console.log("Data length : ",length);
|
|
console.log("Data sequence : ",data_bits);
|
|
|
|
for(var i=0; i < length; i++){
|
|
data.push(String.fromCharCode(parseInt(data_bits.substring(0,8), 2)));
|
|
temp_data += data_bits.substring(0,11);
|
|
current_data += String.fromCharCode(parseInt(data_bits.substring(0,8), 2));
|
|
data_bits = data_bits.substring(8);
|
|
}
|
|
temp_data += "]";
|
|
} else if(mode == 0b0000){
|
|
break;
|
|
} else if(mode == 0b1000){
|
|
//TODO: Kanji mode
|
|
console.log("Unsupported encoding: Kanji Mode");
|
|
break;
|
|
} else if(mode == 0b0111){
|
|
// ECI Mode
|
|
if(data_bits.substring(0,1) == "0"){
|
|
special_encoding = data_bits.substring(0,8);
|
|
data_bits = data_bits.substring(8);
|
|
} else if(data_bits.substring(0,2) == "10"){
|
|
special_encoding = data_bits.substring(0,16);
|
|
data_bits = data_bits.substring(16);
|
|
} else if(data_bits.substring(0,3) == "110"){
|
|
special_encoding = data_bits.substring(0,24);
|
|
data_bits = data_bits.substring(24);
|
|
} else {
|
|
console.log("[ERROR]: Invalid ECI Assignment Number");
|
|
break;
|
|
}
|
|
} else {
|
|
console.log("[ERROR]: Invalid Encoding mode");
|
|
break;
|
|
}
|
|
}
|
|
|
|
return data.join("");
|
|
}
|