/* qr.js -- QR code generator in Javascript (revision 2011-01-19) * Written by Kang Seonghoon . * * This source code is in the public domain; if your jurisdiction does not * recognize the public domain the terms of Creative Commons CC0 license * apply. In the other words, you can always do what you want. */ var QRCode = (function(){ /* Quick overview: QR code composed of 2D array of modules (a rectangular * area that conveys one bit of information); some modules are fixed to help * the recognition of the code, and remaining data modules are further divided * into 8-bit code words which are augumented by Reed-Solomon error correcting * codes (ECC). There could be multiple ECCs, in the case the code is so large * that it is helpful to split the raw data into several chunks. * * The number of modules is determined by the code's "version", ranging from 1 * (21x21) to 40 (177x177). How many ECC bits are used is determined by the * ECC level (L/M/Q/H). The number and size (and thus the order of generator * polynomial) of ECCs depend to the version and ECC level. */ // per-version information (cf. JIS X 0510:2004 pp. 30--36, 71) // // [0]: the degree of generator polynomial by ECC levels // [1]: # of code blocks by ECC levels // [2]: left-top positions of alignment patterns // // the number in this table (in particular, [0]) does not exactly match with // the numbers in the specficiation. see augumenteccs below for the reason. var VERSIONS = [ null, [[10, 7,17,13], [ 1, 1, 1, 1], []], [[16,10,28,22], [ 1, 1, 1, 1], [4,16]], [[26,15,22,18], [ 1, 1, 2, 2], [4,20]], [[18,20,16,26], [ 2, 1, 4, 2], [4,24]], [[24,26,22,18], [ 2, 1, 4, 4], [4,28]], [[16,18,28,24], [ 4, 2, 4, 4], [4,32]], [[18,20,26,18], [ 4, 2, 5, 6], [4,20,36]], [[22,24,26,22], [ 4, 2, 6, 6], [4,22,40]], [[22,30,24,20], [ 5, 2, 8, 8], [4,24,44]], [[26,18,28,24], [ 5, 4, 8, 8], [4,26,48]], [[30,20,24,28], [ 5, 4,11, 8], [4,28,52]], [[22,24,28,26], [ 8, 4,11,10], [4,30,56]], [[22,26,22,24], [ 9, 4,16,12], [4,32,60]], [[24,30,24,20], [ 9, 4,16,16], [4,24,44,64]], [[24,22,24,30], [10, 6,18,12], [4,24,46,68]], [[28,24,30,24], [10, 6,16,17], [4,24,48,72]], [[28,28,28,28], [11, 6,19,16], [4,28,52,76]], [[26,30,28,28], [13, 6,21,18], [4,28,54,80]], [[26,28,26,26], [14, 7,25,21], [4,28,56,84]], [[26,28,28,30], [16, 8,25,20], [4,32,60,88]], [[26,28,30,28], [17, 8,25,23], [4,26,48,70,92]], [[28,28,24,30], [17, 9,34,23], [4,24,48,72,96]], [[28,30,30,30], [18, 9,30,25], [4,28,52,76,100]], [[28,30,30,30], [20,10,32,27], [4,26,52,78,104]], [[28,26,30,30], [21,12,35,29], [4,30,56,82,108]], [[28,28,30,28], [23,12,37,34], [4,28,56,84,112]], [[28,30,30,30], [25,12,40,34], [4,32,60,88,116]], [[28,30,30,30], [26,13,42,35], [4,24,48,72,96,120]], [[28,30,30,30], [28,14,45,38], [4,28,52,76,100,124]], [[28,30,30,30], [29,15,48,40], [4,24,50,76,102,128]], [[28,30,30,30], [31,16,51,43], [4,28,54,80,106,132]], [[28,30,30,30], [33,17,54,45], [4,32,58,84,110,136]], [[28,30,30,30], [35,18,57,48], [4,28,56,84,112,140]], [[28,30,30,30], [37,19,60,51], [4,32,60,88,116,144]], [[28,30,30,30], [38,19,63,53], [4,28,52,76,100,124,148]], [[28,30,30,30], [40,20,66,56], [4,22,48,74,100,126,152]], [[28,30,30,30], [43,21,70,59], [4,26,52,78,104,130,156]], [[28,30,30,30], [45,22,74,62], [4,30,56,82,108,134,160]], [[28,30,30,30], [47,24,77,65], [4,24,52,80,108,136,164]], [[28,30,30,30], [49,25,81,68], [4,28,56,84,112,140,168]]]; // mode constants (cf. Table 2 in JIS X 0510:2004 p. 16) var MODE_TERMINATOR = 0; var MODE_NUMERIC = 1, MODE_ALPHANUMERIC = 2, MODE_OCTET = 4, MODE_KANJI = 8; // validation regexps var NUMERIC_REGEXP = /^\d*$/; var ALPHANUMERIC_REGEXP = /^[A-Za-z0-9 $%*+\-./:]*$/; var ALPHANUMERIC_OUT_REGEXP = /^[A-Z0-9 $%*+\-./:]*$/; // ECC levels (cf. Table 22 in JIS X 0510:2004 p. 45) var ECCLEVEL_L = 1, ECCLEVEL_M = 0, ECCLEVEL_Q = 3, ECCLEVEL_H = 2; // GF(2^8)-to-integer mapping with a reducing polynomial x^8+x^4+x^3+x^2+1 // invariant: GF256_MAP[GF256_INVMAP[i]] == i for all i in [1,256) var GF256_MAP = [], GF256_INVMAP = [-1]; for (var i = 0, v = 1; i < 255; ++i) { GF256_MAP.push(v); GF256_INVMAP[v] = i; v = (v * 2) ^ (v >= 128 ? 0x11d : 0); } // generator polynomials up to degree 30 // (should match with polynomials in JIS X 0510:2004 Appendix A) // // generator polynomial of degree K is product of (x-\alpha^0), (x-\alpha^1), // ..., (x-\alpha^(K-1)). by convention, we omit the K-th coefficient (always 1) // from the result; also other coefficients are written in terms of the exponent // to \alpha to avoid the redundant calculation. (see also calculateecc below.) var GF256_GENPOLY = [[]]; for (var i = 0; i < 30; ++i) { var prevpoly = GF256_GENPOLY[i], poly = []; for (var j = 0; j <= i; ++j) { var a = (j < i ? GF256_MAP[prevpoly[j]] : 0); var b = GF256_MAP[(i + (prevpoly[j-1] || 0)) % 255]; poly.push(GF256_INVMAP[a ^ b]); } GF256_GENPOLY.push(poly); } // alphanumeric character mapping (cf. Table 5 in JIS X 0510:2004 p. 19) var ALPHANUMERIC_MAP = {}; for (var i = 0; i < 45; ++i) { ALPHANUMERIC_MAP['0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ $%*+-./:'.charAt(i)] = i; } // mask functions in terms of row # and column # // (cf. Table 20 in JIS X 0510:2004 p. 42) var MASKFUNCS = [ function(i,j) { return (i+j) % 2 == 0; }, function(i,j) { return i % 2 == 0; }, function(i,j) { return j % 3 == 0; }, function(i,j) { return (i+j) % 3 == 0; }, function(i,j) { return (((i/2)|0) + ((j/3)|0)) % 2 == 0; }, function(i,j) { return (i*j) % 2 + (i*j) % 3 == 0; }, function(i,j) { return ((i*j) % 2 + (i*j) % 3) % 2 == 0; }, function(i,j) { return ((i+j) % 2 + (i*j) % 3) % 2 == 0; }]; // returns true when the version information has to be embeded. var needsverinfo = function(ver) { return ver > 6; }; // returns the size of entire QR code for given version. var getsizebyver = function(ver) { return 4 * ver + 17; }; // returns the number of bits available for code words in this version. var nfullbits = function(ver) { /* * |<--------------- n --------------->| * | |<----- n-17 ---->| | * +-------+ ///+-------+ ---- * | | ///| | ^ * | 9x9 | @@@@@ ///| 9x8 | | * | | # # # @5x5@ # # # | | | * +-------+ @@@@@ +-------+ | * # ---| * ^ | * # | * @@@@@ @@@@@ @@@@@ | n * @5x5@ @5x5@ @5x5@ n-17 * @@@@@ @@@@@ @@@@@ | | * # | | * ////// v | * //////# ---| * +-------+ @@@@@ @@@@@ | * | | @5x5@ @5x5@ | * | 8x9 | @@@@@ @@@@@ | * | | v * +-------+ ---- * * when the entire code has n^2 modules and there are m^2-3 alignment * patterns, we have: * - 225 (= 9x9 + 9x8 + 8x9) modules for finder patterns and * format information; * - 2n-34 (= 2(n-17)) modules for timing patterns; * - 36 (= 3x6 + 6x3) modules for version information, if any; * - 25m^2-75 (= (m^2-3)(5x5)) modules for alignment patterns * if any, but 10m-20 (= 2(m-2)x5) of them overlaps with * timing patterns. */ var v = VERSIONS[ver]; var nbits = 16*ver*ver + 128*ver + 64; // finder, timing and format info. if (needsverinfo(ver)) nbits -= 36; // version information if (v[2].length) { // alignment patterns nbits -= 25 * v[2].length * v[2].length - 10 * v[2].length - 55; } return nbits; }; // returns the number of bits available for data portions (i.e. excludes ECC // bits but includes mode and length bits) in this version and ECC level. var ndatabits = function(ver, ecclevel) { var nbits = nfullbits(ver) & ~7; // no sub-octet code words var v = VERSIONS[ver]; nbits -= 8 * v[0][ecclevel] * v[1][ecclevel]; // ecc bits return nbits; } // returns the number of bits required for the length of data. // (cf. Table 3 in JIS X 0510:2004 p. 16) var ndatalenbits = function(ver, mode) { switch (mode) { case MODE_NUMERIC: return (ver < 10 ? 10 : ver < 27 ? 12 : 14); case MODE_ALPHANUMERIC: return (ver < 10 ? 9 : ver < 27 ? 11 : 13); case MODE_OCTET: return (ver < 10 ? 8 : 16); case MODE_KANJI: return (ver < 10 ? 8 : ver < 27 ? 10 : 12); } }; // returns the maximum length of data possible in given configuration. var getmaxdatalen = function(ver, mode, ecclevel) { var nbits = ndatabits(ver, ecclevel) - 4 - ndatalenbits(ver, mode); // 4 for mode bits switch (mode) { case MODE_NUMERIC: return ((nbits/10) | 0) * 3 + (nbits%10 < 4 ? 0 : nbits%10 < 7 ? 1 : 2); case MODE_ALPHANUMERIC: return ((nbits/11) | 0) * 2 + (nbits%11 < 6 ? 0 : 1); case MODE_OCTET: return (nbits/8) | 0; case MODE_KANJI: return (nbits/13) | 0; } }; // checks if the given data can be encoded in given mode, and returns // the converted data for the further processing if possible. otherwise // returns null. // // this function does not check the length of data; it is a duty of // encode function below (as it depends on the version and ECC level too). var validatedata = function(mode, data) { switch (mode) { case MODE_NUMERIC: if (!data.match(NUMERIC_REGEXP)) return null; return data; case MODE_ALPHANUMERIC: if (!data.match(ALPHANUMERIC_REGEXP)) return null; return data.toUpperCase(); case MODE_OCTET: if (typeof data === 'string') { // encode as utf-8 string var newdata = []; for (var i = 0; i < data.length; ++i) { var ch = data.charCodeAt(i); if (ch < 0x80) { newdata.push(ch); } else if (ch < 0x800) { newdata.push(0xc0 | (ch >> 6), 0x80 | (ch & 0x3f)); } else if (ch < 0x10000) { newdata.push(0xe0 | (ch >> 12), 0x80 | ((ch >> 6) & 0x3f), 0x80 | (ch & 0x3f)); } else { newdata.push(0xf0 | (ch >> 18), 0x80 | ((ch >> 12) & 0x3f), 0x80 | ((ch >> 6) & 0x3f), 0x80 | (ch & 0x3f)); } } return newdata; } else { return data; } } }; // returns the code words (sans ECC bits) for given data and configurations. // requires data to be preprocessed by validatedata. no length check is // performed, and everything has to be checked before calling this function. var encode = function(ver, mode, data, maxbuflen) { var buf = []; var bits = 0, remaining = 8; var datalen = data.length; // this function is intentionally no-op when n=0. var pack = function(x, n) { if (n >= remaining) { buf.push(bits | (x >> (n -= remaining))); while (n >= 8) buf.push((x >> (n -= 8)) & 255); bits = 0; remaining = 8; } if (n > 0) bits |= (x & ((1 << n) - 1)) << (remaining -= n); }; var nlenbits = ndatalenbits(ver, mode); pack(mode, 4); pack(datalen, nlenbits); switch (mode) { case MODE_NUMERIC: for (var i = 2; i < datalen; i += 3) { pack(parseInt(data.substring(i-2,i+1), 10), 10); } pack(parseInt(data.substring(i-2), 10), [0,4,7][datalen%3]); break; case MODE_ALPHANUMERIC: for (var i = 1; i < datalen; i += 2) { pack(ALPHANUMERIC_MAP[data.charAt(i-1)] * 45 + ALPHANUMERIC_MAP[data.charAt(i)], 11); } if (datalen % 2 == 1) { pack(ALPHANUMERIC_MAP[data.charAt(i-1)], 6); } break; case MODE_OCTET: for (var i = 0; i < datalen; ++i) { pack(data[i], 8); } break; }; // final bits. it is possible that adding terminator causes the buffer // to overflow, but then the buffer truncated to the maximum size will // be valid as the truncated terminator mode bits and padding is // identical in appearance (cf. JIS X 0510:2004 sec 8.4.8). pack(MODE_TERMINATOR, 4); if (remaining < 8) buf.push(bits); // the padding to fill up the remaining space. we should not add any // words when the overflow already occurred. while (buf.length + 1 < maxbuflen) buf.push(0xec, 0x11); if (buf.length < maxbuflen) buf.push(0xec); return buf; }; // calculates ECC code words for given code words and generator polynomial. // // this is quite similar to CRC calculation as both Reed-Solomon and CRC use // the certain kind of cyclic codes, which is effectively the division of // zero-augumented polynomial by the generator polynomial. the only difference // is that Reed-Solomon uses GF(2^8), instead of CRC's GF(2), and Reed-Solomon // uses the different generator polynomial than CRC's. var calculateecc = function(poly, genpoly) { var modulus = poly.slice(0); var polylen = poly.length, genpolylen = genpoly.length; for (var i = 0; i < genpolylen; ++i) modulus.push(0); for (var i = 0; i < polylen; ) { var quotient = GF256_INVMAP[modulus[i++]]; if (quotient >= 0) { for (var j = 0; j < genpolylen; ++j) { modulus[i+j] ^= GF256_MAP[(quotient + genpoly[j]) % 255]; } } } return modulus.slice(polylen); }; // auguments ECC code words to given code words. the resulting words are // ready to be encoded in the matrix. // // the much of actual augumenting procedure follows JIS X 0510:2004 sec 8.7. // the code is simplified using the fact that the size of each code & ECC // blocks is almost same; for example, when we have 4 blocks and 46 data words // the number of code words in those blocks are 11, 11, 12, 12 respectively. var augumenteccs = function(poly, nblocks, genpoly) { var subsizes = []; var subsize = (poly.length / nblocks) | 0, subsize0 = 0; var pivot = nblocks - poly.length % nblocks; for (var i = 0; i < pivot; ++i) { subsizes.push(subsize0); subsize0 += subsize; } for (var i = pivot; i < nblocks; ++i) { subsizes.push(subsize0); subsize0 += subsize+1; } subsizes.push(subsize0); var eccs = []; for (var i = 0; i < nblocks; ++i) { eccs.push(calculateecc(poly.slice(subsizes[i], subsizes[i+1]), genpoly)); } var result = []; var nitemsperblock = (poly.length / nblocks) | 0; for (var i = 0; i < nitemsperblock; ++i) { for (var j = 0; j < nblocks; ++j) { result.push(poly[subsizes[j] + i]); } } for (var j = pivot; j < nblocks; ++j) { result.push(poly[subsizes[j+1] - 1]); } for (var i = 0; i < genpoly.length; ++i) { for (var j = 0; j < nblocks; ++j) { result.push(eccs[j][i]); } } return result; }; // auguments BCH(p+q,q) code to the polynomial over GF(2), given the proper // genpoly. the both input and output are in binary numbers, and unlike // calculateecc genpoly should include the 1 bit for the highest degree. // // actual polynomials used for this procedure are as follows: // - p=10, q=5, genpoly=x^10+x^8+x^5+x^4+x^2+x+1 (JIS X 0510:2004 Appendix C) // - p=18, q=6, genpoly=x^12+x^11+x^10+x^9+x^8+x^5+x^2+1 (ibid. Appendix D) var augumentbch = function(poly, p, genpoly, q) { var modulus = poly << q; for (var i = p - 1; i >= 0; --i) { if ((modulus >> (q+i)) & 1) modulus ^= genpoly << i; } return (poly << q) | modulus; }; // creates the base matrix for given version. it returns two matrices, one of // them is the actual one and the another represents the "reserved" portion // (e.g. finder and timing patterns) of the matrix. // // some entries in the matrix may be undefined, rather than 0 or 1. this is // intentional (no initialization needed!), and putdata below will fill // the remaining ones. var makebasematrix = function(ver) { var v = VERSIONS[ver], n = getsizebyver(ver); var matrix = [], reserved = []; for (var i = 0; i < n; ++i) { matrix.push([]); reserved.push([]); } var blit = function(y, x, h, w, bits) { for (var i = 0; i < h; ++i) { for (var j = 0; j < w; ++j) { matrix[y+i][x+j] = (bits[i] >> j) & 1; reserved[y+i][x+j] = 1; } } }; // finder patterns and a part of timing patterns // will also mark the format information area (not yet written) as reserved. blit(0, 0, 9, 9, [0x7f, 0x41, 0x5d, 0x5d, 0x5d, 0x41, 0x17f, 0x00, 0x40]); blit(n-8, 0, 8, 9, [0x100, 0x7f, 0x41, 0x5d, 0x5d, 0x5d, 0x41, 0x7f]); blit(0, n-8, 9, 8, [0xfe, 0x82, 0xba, 0xba, 0xba, 0x82, 0xfe, 0x00, 0x00]); // the rest of timing patterns for (var i = 9; i < n-8; ++i) { matrix[6][i] = matrix[i][6] = ~i & 1; reserved[6][i] = reserved[i][6] = 1; } // alignment patterns var aligns = v[2], m = aligns.length; for (var i = 0; i < m; ++i) { var minj = (i==0 || i==m-1 ? 1 : 0), maxj = (i==0 ? m-1 : m); for (var j = minj; j < maxj; ++j) { blit(aligns[i], aligns[j], 5, 5, [0x1f, 0x11, 0x15, 0x11, 0x1f]); } } // version information if (needsverinfo(ver)) { var code = augumentbch(ver, 6, 0x1f25, 12); var k = 0; for (var i = 0; i < 6; ++i) { for (var j = 0; j < 3; ++j) { matrix[i][(n-11)+j] = matrix[(n-11)+j][i] = (code >> k++) & 1; reserved[i][(n-11)+j] = reserved[(n-11)+j][i] = 1; } } } return {matrix: matrix, reserved: reserved}; }; // fills the data portion (i.e. unmarked in reserved) of the matrix with given // code words. the size of code words should be no more than available bits, // and remaining bits are padded to 0 (cf. JIS X 0510:2004 sec 8.7.3). var putdata = function(matrix, reserved, buf) { var n = matrix.length; var k = 0, dir = -1; for (var i = n-1; i >= 0; i -= 2) { if (i == 6) --i; // skip the entire timing pattern column var jj = (dir < 0 ? n-1 : 0); for (var j = 0; j < n; ++j) { for (var ii = i; ii > i-2; --ii) { if (!reserved[jj][ii]) { // may overflow, but (undefined >> x) // is 0 so it will auto-pad to zero. matrix[jj][ii] = (buf[k >> 3] >> (~k&7)) & 1; ++k; } } jj += dir; } dir = -dir; } return matrix; }; // XOR-masks the data portion of the matrix. repeating the call with the same // arguments will revert the prior call (convenient in the matrix evaluation). var maskdata = function(matrix, reserved, mask) { var maskf = MASKFUNCS[mask]; var n = matrix.length; for (var i = 0; i < n; ++i) { for (var j = 0; j < n; ++j) { if (!reserved[i][j]) matrix[i][j] ^= maskf(i,j); } } return matrix; } // puts the format information. var putformatinfo = function(matrix, reserved, ecclevel, mask) { var n = matrix.length; var code = augumentbch((ecclevel << 3) | mask, 5, 0x537, 10) ^ 0x5412; for (var i = 0; i < 15; ++i) { var r = [0,1,2,3,4,5,7,8,n-7,n-6,n-5,n-4,n-3,n-2,n-1][i]; var c = [n-1,n-2,n-3,n-4,n-5,n-6,n-7,n-8,7,5,4,3,2,1,0][i]; matrix[r][8] = matrix[8][c] = (code >> i) & 1; // we don't have to mark those bits reserved; always done // in makebasematrix above. } return matrix; }; // evaluates the resulting matrix and returns the score (lower is better). // (cf. JIS X 0510:2004 sec 8.8.2) // // the evaluation procedure tries to avoid the problematic patterns naturally // occuring from the original matrix. for example, it penaltizes the patterns // which just look like the finder pattern which will confuse the decoder. // we choose the mask which results in the lowest score among 8 possible ones. // // note: zxing seems to use the same procedure and in many cases its choice // agrees to ours, but sometimes it does not. practically it doesn't matter. var evaluatematrix = function(matrix) { // N1+(k-5) points for each consecutive row of k same-colored modules, // where k >= 5. no overlapping row counts. var PENALTY_CONSECUTIVE = 3; // N2 points for each 2x2 block of same-colored modules. // overlapping block does count. var PENALTY_TWOBYTWO = 3; // N3 points for each pattern with >4W:1B:1W:3B:1W:1B or // 1B:1W:3B:1W:1B:>4W, or their multiples (e.g. highly unlikely, // but 13W:3B:3W:9B:3W:3B counts). var PENALTY_FINDERLIKE = 40; // N4*k points for every (5*k)% deviation from 50% black density. // i.e. k=1 for 55~60% and 40~45%, k=2 for 60~65% and 35~40%, etc. var PENALTY_DENSITY = 10; var evaluategroup = function(groups) { // assumes [W,B,W,B,W,...,B,W] var score = 0; for (var i = 0; i < groups.length; ++i) { if (groups[i] >= 5) score += PENALTY_CONSECUTIVE + (groups[i]-5); } for (var i = 5; i < groups.length; i += 2) { var p = groups[i]; if (groups[i-1] == p && groups[i-2] == 3*p && groups[i-3] == p && groups[i-4] == p && (groups[i-5] >= 4*p || groups[i+1] >= 4*p)) { // this part differs from zxing... score += PENALTY_FINDERLIKE; } } return score; }; var n = matrix.length; var score = 0, nblacks = 0; for (var i = 0; i < n; ++i) { var row = matrix[i]; var groups; // evaluate the current row groups = [0]; // the first empty group of white for (var j = 0; j < n; ) { var k; for (k = 0; j < n && row[j]; ++k) ++j; groups.push(k); for (k = 0; j < n && !row[j]; ++k) ++j; groups.push(k); } score += evaluategroup(groups); // evaluate the current column groups = [0]; for (var j = 0; j < n; ) { var k; for (k = 0; j < n && matrix[j][i]; ++k) ++j; groups.push(k); for (k = 0; j < n && !matrix[j][i]; ++k) ++j; groups.push(k); } score += evaluategroup(groups); // check the 2x2 box and calculate the density var nextrow = matrix[i+1] || []; nblacks += row[0]; for (var j = 1; j < n; ++j) { var p = row[j]; nblacks += p; // at least comparison with next row should be strict... if (row[j-1] == p && nextrow[j] === p && nextrow[j-1] === p) { score += PENALTY_TWOBYTWO; } } } score += PENALTY_DENSITY * ((Math.abs(nblacks / n / n - 0.5) / 0.05) | 0); return score; }; // returns the fully encoded QR code matrix which contains given data. // it also chooses the best mask automatically when mask is -1. var generate = function(data, ver, mode, ecclevel, mask) { var v = VERSIONS[ver]; var buf = encode(ver, mode, data, ndatabits(ver, ecclevel) >> 3); buf = augumenteccs(buf, v[1][ecclevel], GF256_GENPOLY[v[0][ecclevel]]); var result = makebasematrix(ver); var matrix = result.matrix, reserved = result.reserved; putdata(matrix, reserved, buf); if (mask < 0) { // find the best mask maskdata(matrix, reserved, 0); putformatinfo(matrix, reserved, ecclevel, 0); var bestmask = 0, bestscore = evaluatematrix(matrix); maskdata(matrix, reserved, 0); for (mask = 1; mask < 8; ++mask) { maskdata(matrix, reserved, mask); putformatinfo(matrix, reserved, ecclevel, mask); var score = evaluatematrix(matrix); if (bestscore > score) { bestscore = score; bestmask = mask; } maskdata(matrix, reserved, mask); } mask = bestmask; } maskdata(matrix, reserved, mask); putformatinfo(matrix, reserved, ecclevel, mask); return matrix; }; // the public interface is trivial; the options available are as follows: // // - version: an integer in [1,40]. when omitted (or -1) the smallest possible // version is chosen. // - mode: one of 'numeric', 'alphanumeric', 'octet'. when omitted the smallest // possible mode is chosen. // - ecclevel: one of 'L', 'M', 'Q', 'H'. defaults to 'L'. // - mask: an integer in [0,7]. when omitted (or -1) the best mask is chosen. // // for generate{HTML,PNG}: // // - modulesize: a number. this is a size of each modules in pixels, and // defaults to 5px. // - margin: a number. this is a size of margin in *modules*, and defaults to // 4 (white modules). the specficiation mandates the margin no less than 4 // modules, so it is better not to alter this value unless you know what // you're doing. var QRCode = { 'generate': function(data, options) { var MODES = {'numeric': MODE_NUMERIC, 'alphanumeric': MODE_ALPHANUMERIC, 'octet': MODE_OCTET}; var ECCLEVELS = {'L': ECCLEVEL_L, 'M': ECCLEVEL_M, 'Q': ECCLEVEL_Q, 'H': ECCLEVEL_H}; options = options || {}; var ver = options.version || -1; var ecclevel = ECCLEVELS[(options.ecclevel || 'L').toUpperCase()]; var mode = options.mode ? MODES[options.mode.toLowerCase()] : -1; var mask = 'mask' in options ? options.mask : -1; if (mode < 0) { if (typeof data === 'string') { if (data.match(NUMERIC_REGEXP)) { mode = MODE_NUMERIC; } else if (data.match(ALPHANUMERIC_OUT_REGEXP)) { // while encode supports case-insensitive // encoding, we restrict the data to be // uppercased when auto-selecting the mode. mode = MODE_ALPHANUMERIC; } else { mode = MODE_OCTET; } } else { mode = MODE_OCTET; } } else if (!(mode == MODE_NUMERIC || mode == MODE_ALPHANUMERIC || mode == MODE_OCTET)) { throw 'invalid or unsupported mode'; } data = validatedata(mode, data); if (data === null) throw 'invalid data format'; if (ecclevel < 0 || ecclevel > 3) throw 'invalid ECC level'; if (ver < 0) { for (ver = 1; ver <= 40; ++ver) { if (data.length <= getmaxdatalen(ver, mode, ecclevel)) break; } if (ver > 40) throw 'too large data'; } else if (ver < 1 || ver > 40) { throw 'invalid version'; } if (mask != -1 && (mask < 0 || mask > 8)) throw 'invalid mask'; return generate(data, ver, mode, ecclevel, mask); }, 'generateHTML': function(data, options) { options = options || {}; var matrix = QRCode['generate'](data, options); var modsize = Math.max(options.modulesize || 5, 0.5); var margin = Math.max(options.margin || 4, 0.0); var e = document.createElement('div'); var n = matrix.length; var html = ['']; for (var i = 0; i < n; ++i) { html.push(''); for (var j = 0; j < n; ++j) { html.push(''); } html.push(''); } e.className = 'qrcode'; e.innerHTML = html.join('') + '
'; return e; }, 'generatePNG': function(data, options) { options = options || {}; var matrix = QRCode['generate'](data, options); var modsize = Math.max(options.modulesize || 5, 0.5); var margin = Math.max(options.margin || 4, 0.0); var n = matrix.length; var size = modsize * (n + 2 * margin); var canvas = document.createElement('canvas'), context; canvas.width = canvas.height = size; context = canvas.getContext('2d'); if (!context) throw 'canvas support is needed for PNG output'; context.fillStyle = '#fff'; context.fillRect(0, 0, size, size); context.fillStyle = '#000'; for (var i = 0; i < n; ++i) { for (var j = 0; j < n; ++j) { if (matrix[i][j]) { context.fillRect(modsize * (margin + j), modsize * (margin + i), modsize, modsize); } } } //context.fillText('evaluation: ' + evaluatematrix(matrix), 10, 10); return canvas.toDataURL(); } }; return QRCode; })();