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jpg.js 39 KB

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  1. /**
  2. * @licstart The following is the entire license notice for the
  3. * Javascript code in this page
  4. *
  5. * Copyright 2019 Mozilla Foundation
  6. *
  7. * Licensed under the Apache License, Version 2.0 (the "License");
  8. * you may not use this file except in compliance with the License.
  9. * You may obtain a copy of the License at
  10. *
  11. * http://www.apache.org/licenses/LICENSE-2.0
  12. *
  13. * Unless required by applicable law or agreed to in writing, software
  14. * distributed under the License is distributed on an "AS IS" BASIS,
  15. * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16. * See the License for the specific language governing permissions and
  17. * limitations under the License.
  18. *
  19. * @licend The above is the entire license notice for the
  20. * Javascript code in this page
  21. */
  22. "use strict";
  23. Object.defineProperty(exports, "__esModule", {
  24. value: true
  25. });
  26. exports.JpegImage = void 0;
  27. var _util = require("../shared/util");
  28. function _typeof(obj) { if (typeof Symbol === "function" && typeof Symbol.iterator === "symbol") { _typeof = function _typeof(obj) { return typeof obj; }; } else { _typeof = function _typeof(obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }; } return _typeof(obj); }
  29. function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
  30. function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } return _assertThisInitialized(self); }
  31. function _assertThisInitialized(self) { if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
  32. function _getPrototypeOf(o) { _getPrototypeOf = Object.setPrototypeOf ? Object.getPrototypeOf : function _getPrototypeOf(o) { return o.__proto__ || Object.getPrototypeOf(o); }; return _getPrototypeOf(o); }
  33. function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, writable: true, configurable: true } }); if (superClass) _setPrototypeOf(subClass, superClass); }
  34. function _setPrototypeOf(o, p) { _setPrototypeOf = Object.setPrototypeOf || function _setPrototypeOf(o, p) { o.__proto__ = p; return o; }; return _setPrototypeOf(o, p); }
  35. var JpegError =
  36. /*#__PURE__*/
  37. function (_BaseException) {
  38. _inherits(JpegError, _BaseException);
  39. function JpegError(msg) {
  40. _classCallCheck(this, JpegError);
  41. return _possibleConstructorReturn(this, _getPrototypeOf(JpegError).call(this, "JPEG error: ".concat(msg)));
  42. }
  43. return JpegError;
  44. }(_util.BaseException);
  45. var DNLMarkerError =
  46. /*#__PURE__*/
  47. function (_BaseException2) {
  48. _inherits(DNLMarkerError, _BaseException2);
  49. function DNLMarkerError(message, scanLines) {
  50. var _this;
  51. _classCallCheck(this, DNLMarkerError);
  52. _this = _possibleConstructorReturn(this, _getPrototypeOf(DNLMarkerError).call(this, message));
  53. _this.scanLines = scanLines;
  54. return _this;
  55. }
  56. return DNLMarkerError;
  57. }(_util.BaseException);
  58. var EOIMarkerError =
  59. /*#__PURE__*/
  60. function (_BaseException3) {
  61. _inherits(EOIMarkerError, _BaseException3);
  62. function EOIMarkerError() {
  63. _classCallCheck(this, EOIMarkerError);
  64. return _possibleConstructorReturn(this, _getPrototypeOf(EOIMarkerError).apply(this, arguments));
  65. }
  66. return EOIMarkerError;
  67. }(_util.BaseException);
  68. var JpegImage = function JpegImageClosure() {
  69. var dctZigZag = new Uint8Array([0, 1, 8, 16, 9, 2, 3, 10, 17, 24, 32, 25, 18, 11, 4, 5, 12, 19, 26, 33, 40, 48, 41, 34, 27, 20, 13, 6, 7, 14, 21, 28, 35, 42, 49, 56, 57, 50, 43, 36, 29, 22, 15, 23, 30, 37, 44, 51, 58, 59, 52, 45, 38, 31, 39, 46, 53, 60, 61, 54, 47, 55, 62, 63]);
  70. var dctCos1 = 4017;
  71. var dctSin1 = 799;
  72. var dctCos3 = 3406;
  73. var dctSin3 = 2276;
  74. var dctCos6 = 1567;
  75. var dctSin6 = 3784;
  76. var dctSqrt2 = 5793;
  77. var dctSqrt1d2 = 2896;
  78. function JpegImage() {
  79. var _ref = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : {},
  80. _ref$decodeTransform = _ref.decodeTransform,
  81. decodeTransform = _ref$decodeTransform === void 0 ? null : _ref$decodeTransform,
  82. _ref$colorTransform = _ref.colorTransform,
  83. colorTransform = _ref$colorTransform === void 0 ? -1 : _ref$colorTransform;
  84. this._decodeTransform = decodeTransform;
  85. this._colorTransform = colorTransform;
  86. }
  87. function buildHuffmanTable(codeLengths, values) {
  88. var k = 0,
  89. code = [],
  90. i,
  91. j,
  92. length = 16;
  93. while (length > 0 && !codeLengths[length - 1]) {
  94. length--;
  95. }
  96. code.push({
  97. children: [],
  98. index: 0
  99. });
  100. var p = code[0],
  101. q;
  102. for (i = 0; i < length; i++) {
  103. for (j = 0; j < codeLengths[i]; j++) {
  104. p = code.pop();
  105. p.children[p.index] = values[k];
  106. while (p.index > 0) {
  107. p = code.pop();
  108. }
  109. p.index++;
  110. code.push(p);
  111. while (code.length <= i) {
  112. code.push(q = {
  113. children: [],
  114. index: 0
  115. });
  116. p.children[p.index] = q.children;
  117. p = q;
  118. }
  119. k++;
  120. }
  121. if (i + 1 < length) {
  122. code.push(q = {
  123. children: [],
  124. index: 0
  125. });
  126. p.children[p.index] = q.children;
  127. p = q;
  128. }
  129. }
  130. return code[0].children;
  131. }
  132. function getBlockBufferOffset(component, row, col) {
  133. return 64 * ((component.blocksPerLine + 1) * row + col);
  134. }
  135. function decodeScan(data, offset, frame, components, resetInterval, spectralStart, spectralEnd, successivePrev, successive) {
  136. var parseDNLMarker = arguments.length > 9 && arguments[9] !== undefined ? arguments[9] : false;
  137. var mcusPerLine = frame.mcusPerLine;
  138. var progressive = frame.progressive;
  139. var startOffset = offset,
  140. bitsData = 0,
  141. bitsCount = 0;
  142. function readBit() {
  143. if (bitsCount > 0) {
  144. bitsCount--;
  145. return bitsData >> bitsCount & 1;
  146. }
  147. bitsData = data[offset++];
  148. if (bitsData === 0xFF) {
  149. var nextByte = data[offset++];
  150. if (nextByte) {
  151. if (nextByte === 0xDC && parseDNLMarker) {
  152. offset += 2;
  153. var scanLines = data[offset++] << 8 | data[offset++];
  154. if (scanLines > 0 && scanLines !== frame.scanLines) {
  155. throw new DNLMarkerError('Found DNL marker (0xFFDC) while parsing scan data', scanLines);
  156. }
  157. } else if (nextByte === 0xD9) {
  158. throw new EOIMarkerError('Found EOI marker (0xFFD9) while parsing scan data');
  159. }
  160. throw new JpegError("unexpected marker ".concat((bitsData << 8 | nextByte).toString(16)));
  161. }
  162. }
  163. bitsCount = 7;
  164. return bitsData >>> 7;
  165. }
  166. function decodeHuffman(tree) {
  167. var node = tree;
  168. while (true) {
  169. node = node[readBit()];
  170. if (typeof node === 'number') {
  171. return node;
  172. }
  173. if (_typeof(node) !== 'object') {
  174. throw new JpegError('invalid huffman sequence');
  175. }
  176. }
  177. }
  178. function receive(length) {
  179. var n = 0;
  180. while (length > 0) {
  181. n = n << 1 | readBit();
  182. length--;
  183. }
  184. return n;
  185. }
  186. function receiveAndExtend(length) {
  187. if (length === 1) {
  188. return readBit() === 1 ? 1 : -1;
  189. }
  190. var n = receive(length);
  191. if (n >= 1 << length - 1) {
  192. return n;
  193. }
  194. return n + (-1 << length) + 1;
  195. }
  196. function decodeBaseline(component, offset) {
  197. var t = decodeHuffman(component.huffmanTableDC);
  198. var diff = t === 0 ? 0 : receiveAndExtend(t);
  199. component.blockData[offset] = component.pred += diff;
  200. var k = 1;
  201. while (k < 64) {
  202. var rs = decodeHuffman(component.huffmanTableAC);
  203. var s = rs & 15,
  204. r = rs >> 4;
  205. if (s === 0) {
  206. if (r < 15) {
  207. break;
  208. }
  209. k += 16;
  210. continue;
  211. }
  212. k += r;
  213. var z = dctZigZag[k];
  214. component.blockData[offset + z] = receiveAndExtend(s);
  215. k++;
  216. }
  217. }
  218. function decodeDCFirst(component, offset) {
  219. var t = decodeHuffman(component.huffmanTableDC);
  220. var diff = t === 0 ? 0 : receiveAndExtend(t) << successive;
  221. component.blockData[offset] = component.pred += diff;
  222. }
  223. function decodeDCSuccessive(component, offset) {
  224. component.blockData[offset] |= readBit() << successive;
  225. }
  226. var eobrun = 0;
  227. function decodeACFirst(component, offset) {
  228. if (eobrun > 0) {
  229. eobrun--;
  230. return;
  231. }
  232. var k = spectralStart,
  233. e = spectralEnd;
  234. while (k <= e) {
  235. var rs = decodeHuffman(component.huffmanTableAC);
  236. var s = rs & 15,
  237. r = rs >> 4;
  238. if (s === 0) {
  239. if (r < 15) {
  240. eobrun = receive(r) + (1 << r) - 1;
  241. break;
  242. }
  243. k += 16;
  244. continue;
  245. }
  246. k += r;
  247. var z = dctZigZag[k];
  248. component.blockData[offset + z] = receiveAndExtend(s) * (1 << successive);
  249. k++;
  250. }
  251. }
  252. var successiveACState = 0,
  253. successiveACNextValue;
  254. function decodeACSuccessive(component, offset) {
  255. var k = spectralStart;
  256. var e = spectralEnd;
  257. var r = 0;
  258. var s;
  259. var rs;
  260. while (k <= e) {
  261. var offsetZ = offset + dctZigZag[k];
  262. var sign = component.blockData[offsetZ] < 0 ? -1 : 1;
  263. switch (successiveACState) {
  264. case 0:
  265. rs = decodeHuffman(component.huffmanTableAC);
  266. s = rs & 15;
  267. r = rs >> 4;
  268. if (s === 0) {
  269. if (r < 15) {
  270. eobrun = receive(r) + (1 << r);
  271. successiveACState = 4;
  272. } else {
  273. r = 16;
  274. successiveACState = 1;
  275. }
  276. } else {
  277. if (s !== 1) {
  278. throw new JpegError('invalid ACn encoding');
  279. }
  280. successiveACNextValue = receiveAndExtend(s);
  281. successiveACState = r ? 2 : 3;
  282. }
  283. continue;
  284. case 1:
  285. case 2:
  286. if (component.blockData[offsetZ]) {
  287. component.blockData[offsetZ] += sign * (readBit() << successive);
  288. } else {
  289. r--;
  290. if (r === 0) {
  291. successiveACState = successiveACState === 2 ? 3 : 0;
  292. }
  293. }
  294. break;
  295. case 3:
  296. if (component.blockData[offsetZ]) {
  297. component.blockData[offsetZ] += sign * (readBit() << successive);
  298. } else {
  299. component.blockData[offsetZ] = successiveACNextValue << successive;
  300. successiveACState = 0;
  301. }
  302. break;
  303. case 4:
  304. if (component.blockData[offsetZ]) {
  305. component.blockData[offsetZ] += sign * (readBit() << successive);
  306. }
  307. break;
  308. }
  309. k++;
  310. }
  311. if (successiveACState === 4) {
  312. eobrun--;
  313. if (eobrun === 0) {
  314. successiveACState = 0;
  315. }
  316. }
  317. }
  318. function decodeMcu(component, decode, mcu, row, col) {
  319. var mcuRow = mcu / mcusPerLine | 0;
  320. var mcuCol = mcu % mcusPerLine;
  321. var blockRow = mcuRow * component.v + row;
  322. var blockCol = mcuCol * component.h + col;
  323. var offset = getBlockBufferOffset(component, blockRow, blockCol);
  324. decode(component, offset);
  325. }
  326. function decodeBlock(component, decode, mcu) {
  327. var blockRow = mcu / component.blocksPerLine | 0;
  328. var blockCol = mcu % component.blocksPerLine;
  329. var offset = getBlockBufferOffset(component, blockRow, blockCol);
  330. decode(component, offset);
  331. }
  332. var componentsLength = components.length;
  333. var component, i, j, k, n;
  334. var decodeFn;
  335. if (progressive) {
  336. if (spectralStart === 0) {
  337. decodeFn = successivePrev === 0 ? decodeDCFirst : decodeDCSuccessive;
  338. } else {
  339. decodeFn = successivePrev === 0 ? decodeACFirst : decodeACSuccessive;
  340. }
  341. } else {
  342. decodeFn = decodeBaseline;
  343. }
  344. var mcu = 0,
  345. fileMarker;
  346. var mcuExpected;
  347. if (componentsLength === 1) {
  348. mcuExpected = components[0].blocksPerLine * components[0].blocksPerColumn;
  349. } else {
  350. mcuExpected = mcusPerLine * frame.mcusPerColumn;
  351. }
  352. var h, v;
  353. while (mcu < mcuExpected) {
  354. var mcuToRead = resetInterval ? Math.min(mcuExpected - mcu, resetInterval) : mcuExpected;
  355. for (i = 0; i < componentsLength; i++) {
  356. components[i].pred = 0;
  357. }
  358. eobrun = 0;
  359. if (componentsLength === 1) {
  360. component = components[0];
  361. for (n = 0; n < mcuToRead; n++) {
  362. decodeBlock(component, decodeFn, mcu);
  363. mcu++;
  364. }
  365. } else {
  366. for (n = 0; n < mcuToRead; n++) {
  367. for (i = 0; i < componentsLength; i++) {
  368. component = components[i];
  369. h = component.h;
  370. v = component.v;
  371. for (j = 0; j < v; j++) {
  372. for (k = 0; k < h; k++) {
  373. decodeMcu(component, decodeFn, mcu, j, k);
  374. }
  375. }
  376. }
  377. mcu++;
  378. }
  379. }
  380. bitsCount = 0;
  381. fileMarker = findNextFileMarker(data, offset);
  382. if (!fileMarker) {
  383. break;
  384. } else if (fileMarker.invalid) {
  385. (0, _util.warn)('decodeScan - unexpected MCU data, current marker is: ' + fileMarker.invalid);
  386. offset = fileMarker.offset;
  387. }
  388. var marker = fileMarker && fileMarker.marker;
  389. if (!marker || marker <= 0xFF00) {
  390. throw new JpegError('decodeScan - a valid marker was not found.');
  391. }
  392. if (marker >= 0xFFD0 && marker <= 0xFFD7) {
  393. offset += 2;
  394. } else {
  395. break;
  396. }
  397. }
  398. fileMarker = findNextFileMarker(data, offset);
  399. if (fileMarker && fileMarker.invalid) {
  400. (0, _util.warn)('decodeScan - unexpected Scan data, current marker is: ' + fileMarker.invalid);
  401. offset = fileMarker.offset;
  402. }
  403. return offset - startOffset;
  404. }
  405. function quantizeAndInverse(component, blockBufferOffset, p) {
  406. var qt = component.quantizationTable,
  407. blockData = component.blockData;
  408. var v0, v1, v2, v3, v4, v5, v6, v7;
  409. var p0, p1, p2, p3, p4, p5, p6, p7;
  410. var t;
  411. if (!qt) {
  412. throw new JpegError('missing required Quantization Table.');
  413. }
  414. for (var row = 0; row < 64; row += 8) {
  415. p0 = blockData[blockBufferOffset + row];
  416. p1 = blockData[blockBufferOffset + row + 1];
  417. p2 = blockData[blockBufferOffset + row + 2];
  418. p3 = blockData[blockBufferOffset + row + 3];
  419. p4 = blockData[blockBufferOffset + row + 4];
  420. p5 = blockData[blockBufferOffset + row + 5];
  421. p6 = blockData[blockBufferOffset + row + 6];
  422. p7 = blockData[blockBufferOffset + row + 7];
  423. p0 *= qt[row];
  424. if ((p1 | p2 | p3 | p4 | p5 | p6 | p7) === 0) {
  425. t = dctSqrt2 * p0 + 512 >> 10;
  426. p[row] = t;
  427. p[row + 1] = t;
  428. p[row + 2] = t;
  429. p[row + 3] = t;
  430. p[row + 4] = t;
  431. p[row + 5] = t;
  432. p[row + 6] = t;
  433. p[row + 7] = t;
  434. continue;
  435. }
  436. p1 *= qt[row + 1];
  437. p2 *= qt[row + 2];
  438. p3 *= qt[row + 3];
  439. p4 *= qt[row + 4];
  440. p5 *= qt[row + 5];
  441. p6 *= qt[row + 6];
  442. p7 *= qt[row + 7];
  443. v0 = dctSqrt2 * p0 + 128 >> 8;
  444. v1 = dctSqrt2 * p4 + 128 >> 8;
  445. v2 = p2;
  446. v3 = p6;
  447. v4 = dctSqrt1d2 * (p1 - p7) + 128 >> 8;
  448. v7 = dctSqrt1d2 * (p1 + p7) + 128 >> 8;
  449. v5 = p3 << 4;
  450. v6 = p5 << 4;
  451. v0 = v0 + v1 + 1 >> 1;
  452. v1 = v0 - v1;
  453. t = v2 * dctSin6 + v3 * dctCos6 + 128 >> 8;
  454. v2 = v2 * dctCos6 - v3 * dctSin6 + 128 >> 8;
  455. v3 = t;
  456. v4 = v4 + v6 + 1 >> 1;
  457. v6 = v4 - v6;
  458. v7 = v7 + v5 + 1 >> 1;
  459. v5 = v7 - v5;
  460. v0 = v0 + v3 + 1 >> 1;
  461. v3 = v0 - v3;
  462. v1 = v1 + v2 + 1 >> 1;
  463. v2 = v1 - v2;
  464. t = v4 * dctSin3 + v7 * dctCos3 + 2048 >> 12;
  465. v4 = v4 * dctCos3 - v7 * dctSin3 + 2048 >> 12;
  466. v7 = t;
  467. t = v5 * dctSin1 + v6 * dctCos1 + 2048 >> 12;
  468. v5 = v5 * dctCos1 - v6 * dctSin1 + 2048 >> 12;
  469. v6 = t;
  470. p[row] = v0 + v7;
  471. p[row + 7] = v0 - v7;
  472. p[row + 1] = v1 + v6;
  473. p[row + 6] = v1 - v6;
  474. p[row + 2] = v2 + v5;
  475. p[row + 5] = v2 - v5;
  476. p[row + 3] = v3 + v4;
  477. p[row + 4] = v3 - v4;
  478. }
  479. for (var col = 0; col < 8; ++col) {
  480. p0 = p[col];
  481. p1 = p[col + 8];
  482. p2 = p[col + 16];
  483. p3 = p[col + 24];
  484. p4 = p[col + 32];
  485. p5 = p[col + 40];
  486. p6 = p[col + 48];
  487. p7 = p[col + 56];
  488. if ((p1 | p2 | p3 | p4 | p5 | p6 | p7) === 0) {
  489. t = dctSqrt2 * p0 + 8192 >> 14;
  490. t = t < -2040 ? 0 : t >= 2024 ? 255 : t + 2056 >> 4;
  491. blockData[blockBufferOffset + col] = t;
  492. blockData[blockBufferOffset + col + 8] = t;
  493. blockData[blockBufferOffset + col + 16] = t;
  494. blockData[blockBufferOffset + col + 24] = t;
  495. blockData[blockBufferOffset + col + 32] = t;
  496. blockData[blockBufferOffset + col + 40] = t;
  497. blockData[blockBufferOffset + col + 48] = t;
  498. blockData[blockBufferOffset + col + 56] = t;
  499. continue;
  500. }
  501. v0 = dctSqrt2 * p0 + 2048 >> 12;
  502. v1 = dctSqrt2 * p4 + 2048 >> 12;
  503. v2 = p2;
  504. v3 = p6;
  505. v4 = dctSqrt1d2 * (p1 - p7) + 2048 >> 12;
  506. v7 = dctSqrt1d2 * (p1 + p7) + 2048 >> 12;
  507. v5 = p3;
  508. v6 = p5;
  509. v0 = (v0 + v1 + 1 >> 1) + 4112;
  510. v1 = v0 - v1;
  511. t = v2 * dctSin6 + v3 * dctCos6 + 2048 >> 12;
  512. v2 = v2 * dctCos6 - v3 * dctSin6 + 2048 >> 12;
  513. v3 = t;
  514. v4 = v4 + v6 + 1 >> 1;
  515. v6 = v4 - v6;
  516. v7 = v7 + v5 + 1 >> 1;
  517. v5 = v7 - v5;
  518. v0 = v0 + v3 + 1 >> 1;
  519. v3 = v0 - v3;
  520. v1 = v1 + v2 + 1 >> 1;
  521. v2 = v1 - v2;
  522. t = v4 * dctSin3 + v7 * dctCos3 + 2048 >> 12;
  523. v4 = v4 * dctCos3 - v7 * dctSin3 + 2048 >> 12;
  524. v7 = t;
  525. t = v5 * dctSin1 + v6 * dctCos1 + 2048 >> 12;
  526. v5 = v5 * dctCos1 - v6 * dctSin1 + 2048 >> 12;
  527. v6 = t;
  528. p0 = v0 + v7;
  529. p7 = v0 - v7;
  530. p1 = v1 + v6;
  531. p6 = v1 - v6;
  532. p2 = v2 + v5;
  533. p5 = v2 - v5;
  534. p3 = v3 + v4;
  535. p4 = v3 - v4;
  536. p0 = p0 < 16 ? 0 : p0 >= 4080 ? 255 : p0 >> 4;
  537. p1 = p1 < 16 ? 0 : p1 >= 4080 ? 255 : p1 >> 4;
  538. p2 = p2 < 16 ? 0 : p2 >= 4080 ? 255 : p2 >> 4;
  539. p3 = p3 < 16 ? 0 : p3 >= 4080 ? 255 : p3 >> 4;
  540. p4 = p4 < 16 ? 0 : p4 >= 4080 ? 255 : p4 >> 4;
  541. p5 = p5 < 16 ? 0 : p5 >= 4080 ? 255 : p5 >> 4;
  542. p6 = p6 < 16 ? 0 : p6 >= 4080 ? 255 : p6 >> 4;
  543. p7 = p7 < 16 ? 0 : p7 >= 4080 ? 255 : p7 >> 4;
  544. blockData[blockBufferOffset + col] = p0;
  545. blockData[blockBufferOffset + col + 8] = p1;
  546. blockData[blockBufferOffset + col + 16] = p2;
  547. blockData[blockBufferOffset + col + 24] = p3;
  548. blockData[blockBufferOffset + col + 32] = p4;
  549. blockData[blockBufferOffset + col + 40] = p5;
  550. blockData[blockBufferOffset + col + 48] = p6;
  551. blockData[blockBufferOffset + col + 56] = p7;
  552. }
  553. }
  554. function buildComponentData(frame, component) {
  555. var blocksPerLine = component.blocksPerLine;
  556. var blocksPerColumn = component.blocksPerColumn;
  557. var computationBuffer = new Int16Array(64);
  558. for (var blockRow = 0; blockRow < blocksPerColumn; blockRow++) {
  559. for (var blockCol = 0; blockCol < blocksPerLine; blockCol++) {
  560. var offset = getBlockBufferOffset(component, blockRow, blockCol);
  561. quantizeAndInverse(component, offset, computationBuffer);
  562. }
  563. }
  564. return component.blockData;
  565. }
  566. function findNextFileMarker(data, currentPos) {
  567. var startPos = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : currentPos;
  568. function peekUint16(pos) {
  569. return data[pos] << 8 | data[pos + 1];
  570. }
  571. var maxPos = data.length - 1;
  572. var newPos = startPos < currentPos ? startPos : currentPos;
  573. if (currentPos >= maxPos) {
  574. return null;
  575. }
  576. var currentMarker = peekUint16(currentPos);
  577. if (currentMarker >= 0xFFC0 && currentMarker <= 0xFFFE) {
  578. return {
  579. invalid: null,
  580. marker: currentMarker,
  581. offset: currentPos
  582. };
  583. }
  584. var newMarker = peekUint16(newPos);
  585. while (!(newMarker >= 0xFFC0 && newMarker <= 0xFFFE)) {
  586. if (++newPos >= maxPos) {
  587. return null;
  588. }
  589. newMarker = peekUint16(newPos);
  590. }
  591. return {
  592. invalid: currentMarker.toString(16),
  593. marker: newMarker,
  594. offset: newPos
  595. };
  596. }
  597. JpegImage.prototype = {
  598. parse: function parse(data) {
  599. var _ref2 = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {},
  600. _ref2$dnlScanLines = _ref2.dnlScanLines,
  601. dnlScanLines = _ref2$dnlScanLines === void 0 ? null : _ref2$dnlScanLines;
  602. function readUint16() {
  603. var value = data[offset] << 8 | data[offset + 1];
  604. offset += 2;
  605. return value;
  606. }
  607. function readDataBlock() {
  608. var length = readUint16();
  609. var endOffset = offset + length - 2;
  610. var fileMarker = findNextFileMarker(data, endOffset, offset);
  611. if (fileMarker && fileMarker.invalid) {
  612. (0, _util.warn)('readDataBlock - incorrect length, current marker is: ' + fileMarker.invalid);
  613. endOffset = fileMarker.offset;
  614. }
  615. var array = data.subarray(offset, endOffset);
  616. offset += array.length;
  617. return array;
  618. }
  619. function prepareComponents(frame) {
  620. var mcusPerLine = Math.ceil(frame.samplesPerLine / 8 / frame.maxH);
  621. var mcusPerColumn = Math.ceil(frame.scanLines / 8 / frame.maxV);
  622. for (var i = 0; i < frame.components.length; i++) {
  623. component = frame.components[i];
  624. var blocksPerLine = Math.ceil(Math.ceil(frame.samplesPerLine / 8) * component.h / frame.maxH);
  625. var blocksPerColumn = Math.ceil(Math.ceil(frame.scanLines / 8) * component.v / frame.maxV);
  626. var blocksPerLineForMcu = mcusPerLine * component.h;
  627. var blocksPerColumnForMcu = mcusPerColumn * component.v;
  628. var blocksBufferSize = 64 * blocksPerColumnForMcu * (blocksPerLineForMcu + 1);
  629. component.blockData = new Int16Array(blocksBufferSize);
  630. component.blocksPerLine = blocksPerLine;
  631. component.blocksPerColumn = blocksPerColumn;
  632. }
  633. frame.mcusPerLine = mcusPerLine;
  634. frame.mcusPerColumn = mcusPerColumn;
  635. }
  636. var offset = 0;
  637. var jfif = null;
  638. var adobe = null;
  639. var frame, resetInterval;
  640. var numSOSMarkers = 0;
  641. var quantizationTables = [];
  642. var huffmanTablesAC = [],
  643. huffmanTablesDC = [];
  644. var fileMarker = readUint16();
  645. if (fileMarker !== 0xFFD8) {
  646. throw new JpegError('SOI not found');
  647. }
  648. fileMarker = readUint16();
  649. markerLoop: while (fileMarker !== 0xFFD9) {
  650. var i, j, l;
  651. switch (fileMarker) {
  652. case 0xFFE0:
  653. case 0xFFE1:
  654. case 0xFFE2:
  655. case 0xFFE3:
  656. case 0xFFE4:
  657. case 0xFFE5:
  658. case 0xFFE6:
  659. case 0xFFE7:
  660. case 0xFFE8:
  661. case 0xFFE9:
  662. case 0xFFEA:
  663. case 0xFFEB:
  664. case 0xFFEC:
  665. case 0xFFED:
  666. case 0xFFEE:
  667. case 0xFFEF:
  668. case 0xFFFE:
  669. var appData = readDataBlock();
  670. if (fileMarker === 0xFFE0) {
  671. if (appData[0] === 0x4A && appData[1] === 0x46 && appData[2] === 0x49 && appData[3] === 0x46 && appData[4] === 0) {
  672. jfif = {
  673. version: {
  674. major: appData[5],
  675. minor: appData[6]
  676. },
  677. densityUnits: appData[7],
  678. xDensity: appData[8] << 8 | appData[9],
  679. yDensity: appData[10] << 8 | appData[11],
  680. thumbWidth: appData[12],
  681. thumbHeight: appData[13],
  682. thumbData: appData.subarray(14, 14 + 3 * appData[12] * appData[13])
  683. };
  684. }
  685. }
  686. if (fileMarker === 0xFFEE) {
  687. if (appData[0] === 0x41 && appData[1] === 0x64 && appData[2] === 0x6F && appData[3] === 0x62 && appData[4] === 0x65) {
  688. adobe = {
  689. version: appData[5] << 8 | appData[6],
  690. flags0: appData[7] << 8 | appData[8],
  691. flags1: appData[9] << 8 | appData[10],
  692. transformCode: appData[11]
  693. };
  694. }
  695. }
  696. break;
  697. case 0xFFDB:
  698. var quantizationTablesLength = readUint16();
  699. var quantizationTablesEnd = quantizationTablesLength + offset - 2;
  700. var z;
  701. while (offset < quantizationTablesEnd) {
  702. var quantizationTableSpec = data[offset++];
  703. var tableData = new Uint16Array(64);
  704. if (quantizationTableSpec >> 4 === 0) {
  705. for (j = 0; j < 64; j++) {
  706. z = dctZigZag[j];
  707. tableData[z] = data[offset++];
  708. }
  709. } else if (quantizationTableSpec >> 4 === 1) {
  710. for (j = 0; j < 64; j++) {
  711. z = dctZigZag[j];
  712. tableData[z] = readUint16();
  713. }
  714. } else {
  715. throw new JpegError('DQT - invalid table spec');
  716. }
  717. quantizationTables[quantizationTableSpec & 15] = tableData;
  718. }
  719. break;
  720. case 0xFFC0:
  721. case 0xFFC1:
  722. case 0xFFC2:
  723. if (frame) {
  724. throw new JpegError('Only single frame JPEGs supported');
  725. }
  726. readUint16();
  727. frame = {};
  728. frame.extended = fileMarker === 0xFFC1;
  729. frame.progressive = fileMarker === 0xFFC2;
  730. frame.precision = data[offset++];
  731. var sofScanLines = readUint16();
  732. frame.scanLines = dnlScanLines || sofScanLines;
  733. frame.samplesPerLine = readUint16();
  734. frame.components = [];
  735. frame.componentIds = {};
  736. var componentsCount = data[offset++],
  737. componentId;
  738. var maxH = 0,
  739. maxV = 0;
  740. for (i = 0; i < componentsCount; i++) {
  741. componentId = data[offset];
  742. var h = data[offset + 1] >> 4;
  743. var v = data[offset + 1] & 15;
  744. if (maxH < h) {
  745. maxH = h;
  746. }
  747. if (maxV < v) {
  748. maxV = v;
  749. }
  750. var qId = data[offset + 2];
  751. l = frame.components.push({
  752. h: h,
  753. v: v,
  754. quantizationId: qId,
  755. quantizationTable: null
  756. });
  757. frame.componentIds[componentId] = l - 1;
  758. offset += 3;
  759. }
  760. frame.maxH = maxH;
  761. frame.maxV = maxV;
  762. prepareComponents(frame);
  763. break;
  764. case 0xFFC4:
  765. var huffmanLength = readUint16();
  766. for (i = 2; i < huffmanLength;) {
  767. var huffmanTableSpec = data[offset++];
  768. var codeLengths = new Uint8Array(16);
  769. var codeLengthSum = 0;
  770. for (j = 0; j < 16; j++, offset++) {
  771. codeLengthSum += codeLengths[j] = data[offset];
  772. }
  773. var huffmanValues = new Uint8Array(codeLengthSum);
  774. for (j = 0; j < codeLengthSum; j++, offset++) {
  775. huffmanValues[j] = data[offset];
  776. }
  777. i += 17 + codeLengthSum;
  778. (huffmanTableSpec >> 4 === 0 ? huffmanTablesDC : huffmanTablesAC)[huffmanTableSpec & 15] = buildHuffmanTable(codeLengths, huffmanValues);
  779. }
  780. break;
  781. case 0xFFDD:
  782. readUint16();
  783. resetInterval = readUint16();
  784. break;
  785. case 0xFFDA:
  786. var parseDNLMarker = ++numSOSMarkers === 1 && !dnlScanLines;
  787. readUint16();
  788. var selectorsCount = data[offset++];
  789. var components = [],
  790. component;
  791. for (i = 0; i < selectorsCount; i++) {
  792. var componentIndex = frame.componentIds[data[offset++]];
  793. component = frame.components[componentIndex];
  794. var tableSpec = data[offset++];
  795. component.huffmanTableDC = huffmanTablesDC[tableSpec >> 4];
  796. component.huffmanTableAC = huffmanTablesAC[tableSpec & 15];
  797. components.push(component);
  798. }
  799. var spectralStart = data[offset++];
  800. var spectralEnd = data[offset++];
  801. var successiveApproximation = data[offset++];
  802. try {
  803. var processed = decodeScan(data, offset, frame, components, resetInterval, spectralStart, spectralEnd, successiveApproximation >> 4, successiveApproximation & 15, parseDNLMarker);
  804. offset += processed;
  805. } catch (ex) {
  806. if (ex instanceof DNLMarkerError) {
  807. (0, _util.warn)("".concat(ex.message, " -- attempting to re-parse the JPEG image."));
  808. return this.parse(data, {
  809. dnlScanLines: ex.scanLines
  810. });
  811. } else if (ex instanceof EOIMarkerError) {
  812. (0, _util.warn)("".concat(ex.message, " -- ignoring the rest of the image data."));
  813. break markerLoop;
  814. }
  815. throw ex;
  816. }
  817. break;
  818. case 0xFFDC:
  819. offset += 4;
  820. break;
  821. case 0xFFFF:
  822. if (data[offset] !== 0xFF) {
  823. offset--;
  824. }
  825. break;
  826. default:
  827. if (data[offset - 3] === 0xFF && data[offset - 2] >= 0xC0 && data[offset - 2] <= 0xFE) {
  828. offset -= 3;
  829. break;
  830. }
  831. var nextFileMarker = findNextFileMarker(data, offset - 2);
  832. if (nextFileMarker && nextFileMarker.invalid) {
  833. (0, _util.warn)('JpegImage.parse - unexpected data, current marker is: ' + nextFileMarker.invalid);
  834. offset = nextFileMarker.offset;
  835. break;
  836. }
  837. if (offset > data.length - 2) {
  838. (0, _util.warn)('JpegImage.parse - reached the end of the image data ' + 'without finding an EOI marker (0xFFD9).');
  839. break markerLoop;
  840. }
  841. throw new JpegError('JpegImage.parse - unknown marker: ' + fileMarker.toString(16));
  842. }
  843. fileMarker = readUint16();
  844. }
  845. this.width = frame.samplesPerLine;
  846. this.height = frame.scanLines;
  847. this.jfif = jfif;
  848. this.adobe = adobe;
  849. this.components = [];
  850. for (i = 0; i < frame.components.length; i++) {
  851. component = frame.components[i];
  852. var quantizationTable = quantizationTables[component.quantizationId];
  853. if (quantizationTable) {
  854. component.quantizationTable = quantizationTable;
  855. }
  856. this.components.push({
  857. output: buildComponentData(frame, component),
  858. scaleX: component.h / frame.maxH,
  859. scaleY: component.v / frame.maxV,
  860. blocksPerLine: component.blocksPerLine,
  861. blocksPerColumn: component.blocksPerColumn
  862. });
  863. }
  864. this.numComponents = this.components.length;
  865. return undefined;
  866. },
  867. _getLinearizedBlockData: function _getLinearizedBlockData(width, height) {
  868. var isSourcePDF = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : false;
  869. var scaleX = this.width / width,
  870. scaleY = this.height / height;
  871. var component, componentScaleX, componentScaleY, blocksPerScanline;
  872. var x, y, i, j, k;
  873. var index;
  874. var offset = 0;
  875. var output;
  876. var numComponents = this.components.length;
  877. var dataLength = width * height * numComponents;
  878. var data = new Uint8ClampedArray(dataLength);
  879. var xScaleBlockOffset = new Uint32Array(width);
  880. var mask3LSB = 0xfffffff8;
  881. for (i = 0; i < numComponents; i++) {
  882. component = this.components[i];
  883. componentScaleX = component.scaleX * scaleX;
  884. componentScaleY = component.scaleY * scaleY;
  885. offset = i;
  886. output = component.output;
  887. blocksPerScanline = component.blocksPerLine + 1 << 3;
  888. for (x = 0; x < width; x++) {
  889. j = 0 | x * componentScaleX;
  890. xScaleBlockOffset[x] = (j & mask3LSB) << 3 | j & 7;
  891. }
  892. for (y = 0; y < height; y++) {
  893. j = 0 | y * componentScaleY;
  894. index = blocksPerScanline * (j & mask3LSB) | (j & 7) << 3;
  895. for (x = 0; x < width; x++) {
  896. data[offset] = output[index + xScaleBlockOffset[x]];
  897. offset += numComponents;
  898. }
  899. }
  900. }
  901. var transform = this._decodeTransform;
  902. if (!isSourcePDF && numComponents === 4 && !transform) {
  903. transform = new Int32Array([-256, 255, -256, 255, -256, 255, -256, 255]);
  904. }
  905. if (transform) {
  906. for (i = 0; i < dataLength;) {
  907. for (j = 0, k = 0; j < numComponents; j++, i++, k += 2) {
  908. data[i] = (data[i] * transform[k] >> 8) + transform[k + 1];
  909. }
  910. }
  911. }
  912. return data;
  913. },
  914. get _isColorConversionNeeded() {
  915. if (this.adobe) {
  916. return !!this.adobe.transformCode;
  917. }
  918. if (this.numComponents === 3) {
  919. if (this._colorTransform === 0) {
  920. return false;
  921. }
  922. return true;
  923. }
  924. if (this._colorTransform === 1) {
  925. return true;
  926. }
  927. return false;
  928. },
  929. _convertYccToRgb: function convertYccToRgb(data) {
  930. var Y, Cb, Cr;
  931. for (var i = 0, length = data.length; i < length; i += 3) {
  932. Y = data[i];
  933. Cb = data[i + 1];
  934. Cr = data[i + 2];
  935. data[i] = Y - 179.456 + 1.402 * Cr;
  936. data[i + 1] = Y + 135.459 - 0.344 * Cb - 0.714 * Cr;
  937. data[i + 2] = Y - 226.816 + 1.772 * Cb;
  938. }
  939. return data;
  940. },
  941. _convertYcckToRgb: function convertYcckToRgb(data) {
  942. var Y, Cb, Cr, k;
  943. var offset = 0;
  944. for (var i = 0, length = data.length; i < length; i += 4) {
  945. Y = data[i];
  946. Cb = data[i + 1];
  947. Cr = data[i + 2];
  948. k = data[i + 3];
  949. data[offset++] = -122.67195406894 + Cb * (-6.60635669420364e-5 * Cb + 0.000437130475926232 * Cr - 5.4080610064599e-5 * Y + 0.00048449797120281 * k - 0.154362151871126) + Cr * (-0.000957964378445773 * Cr + 0.000817076911346625 * Y - 0.00477271405408747 * k + 1.53380253221734) + Y * (0.000961250184130688 * Y - 0.00266257332283933 * k + 0.48357088451265) + k * (-0.000336197177618394 * k + 0.484791561490776);
  950. data[offset++] = 107.268039397724 + Cb * (2.19927104525741e-5 * Cb - 0.000640992018297945 * Cr + 0.000659397001245577 * Y + 0.000426105652938837 * k - 0.176491792462875) + Cr * (-0.000778269941513683 * Cr + 0.00130872261408275 * Y + 0.000770482631801132 * k - 0.151051492775562) + Y * (0.00126935368114843 * Y - 0.00265090189010898 * k + 0.25802910206845) + k * (-0.000318913117588328 * k - 0.213742400323665);
  951. data[offset++] = -20.810012546947 + Cb * (-0.000570115196973677 * Cb - 2.63409051004589e-5 * Cr + 0.0020741088115012 * Y - 0.00288260236853442 * k + 0.814272968359295) + Cr * (-1.53496057440975e-5 * Cr - 0.000132689043961446 * Y + 0.000560833691242812 * k - 0.195152027534049) + Y * (0.00174418132927582 * Y - 0.00255243321439347 * k + 0.116935020465145) + k * (-0.000343531996510555 * k + 0.24165260232407);
  952. }
  953. return data.subarray(0, offset);
  954. },
  955. _convertYcckToCmyk: function convertYcckToCmyk(data) {
  956. var Y, Cb, Cr;
  957. for (var i = 0, length = data.length; i < length; i += 4) {
  958. Y = data[i];
  959. Cb = data[i + 1];
  960. Cr = data[i + 2];
  961. data[i] = 434.456 - Y - 1.402 * Cr;
  962. data[i + 1] = 119.541 - Y + 0.344 * Cb + 0.714 * Cr;
  963. data[i + 2] = 481.816 - Y - 1.772 * Cb;
  964. }
  965. return data;
  966. },
  967. _convertCmykToRgb: function convertCmykToRgb(data) {
  968. var c, m, y, k;
  969. var offset = 0;
  970. var scale = 1 / 255;
  971. for (var i = 0, length = data.length; i < length; i += 4) {
  972. c = data[i] * scale;
  973. m = data[i + 1] * scale;
  974. y = data[i + 2] * scale;
  975. k = data[i + 3] * scale;
  976. data[offset++] = 255 + c * (-4.387332384609988 * c + 54.48615194189176 * m + 18.82290502165302 * y + 212.25662451639585 * k - 285.2331026137004) + m * (1.7149763477362134 * m - 5.6096736904047315 * y - 17.873870861415444 * k - 5.497006427196366) + y * (-2.5217340131683033 * y - 21.248923337353073 * k + 17.5119270841813) - k * (21.86122147463605 * k + 189.48180835922747);
  977. data[offset++] = 255 + c * (8.841041422036149 * c + 60.118027045597366 * m + 6.871425592049007 * y + 31.159100130055922 * k - 79.2970844816548) + m * (-15.310361306967817 * m + 17.575251261109482 * y + 131.35250912493976 * k - 190.9453302588951) + y * (4.444339102852739 * y + 9.8632861493405 * k - 24.86741582555878) - k * (20.737325471181034 * k + 187.80453709719578);
  978. data[offset++] = 255 + c * (0.8842522430003296 * c + 8.078677503112928 * m + 30.89978309703729 * y - 0.23883238689178934 * k - 14.183576799673286) + m * (10.49593273432072 * m + 63.02378494754052 * y + 50.606957656360734 * k - 112.23884253719248) + y * (0.03296041114873217 * y + 115.60384449646641 * k - 193.58209356861505) - k * (22.33816807309886 * k + 180.12613974708367);
  979. }
  980. return data.subarray(0, offset);
  981. },
  982. getData: function getData(_ref3) {
  983. var width = _ref3.width,
  984. height = _ref3.height,
  985. _ref3$forceRGB = _ref3.forceRGB,
  986. forceRGB = _ref3$forceRGB === void 0 ? false : _ref3$forceRGB,
  987. _ref3$isSourcePDF = _ref3.isSourcePDF,
  988. isSourcePDF = _ref3$isSourcePDF === void 0 ? false : _ref3$isSourcePDF;
  989. if (this.numComponents > 4) {
  990. throw new JpegError('Unsupported color mode');
  991. }
  992. var data = this._getLinearizedBlockData(width, height, isSourcePDF);
  993. if (this.numComponents === 1 && forceRGB) {
  994. var dataLength = data.length;
  995. var rgbData = new Uint8ClampedArray(dataLength * 3);
  996. var offset = 0;
  997. for (var i = 0; i < dataLength; i++) {
  998. var grayColor = data[i];
  999. rgbData[offset++] = grayColor;
  1000. rgbData[offset++] = grayColor;
  1001. rgbData[offset++] = grayColor;
  1002. }
  1003. return rgbData;
  1004. } else if (this.numComponents === 3 && this._isColorConversionNeeded) {
  1005. return this._convertYccToRgb(data);
  1006. } else if (this.numComponents === 4) {
  1007. if (this._isColorConversionNeeded) {
  1008. if (forceRGB) {
  1009. return this._convertYcckToRgb(data);
  1010. }
  1011. return this._convertYcckToCmyk(data);
  1012. } else if (forceRGB) {
  1013. return this._convertCmykToRgb(data);
  1014. }
  1015. }
  1016. return data;
  1017. }
  1018. };
  1019. return JpegImage;
  1020. }();
  1021. exports.JpegImage = JpegImage;