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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 2018 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
24Object.defineProperty(exports, "__esModule", {
25 value: true
26});
27exports.JpegImage = void 0;
28
29var _util = require("../shared/util");
30
31function _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); }
32
33var JpegError = function JpegErrorClosure() {
34 function JpegError(msg) {
35 this.message = 'JPEG error: ' + msg;
36 }
37
38 JpegError.prototype = new Error();
39 JpegError.prototype.name = 'JpegError';
40 JpegError.constructor = JpegError;
41 return JpegError;
42}();
43
44var DNLMarkerError = function DNLMarkerErrorClosure() {
45 function DNLMarkerError(message, scanLines) {
46 this.message = message;
47 this.scanLines = scanLines;
48 }
49
50 DNLMarkerError.prototype = new Error();
51 DNLMarkerError.prototype.name = 'DNLMarkerError';
52 DNLMarkerError.constructor = DNLMarkerError;
53 return DNLMarkerError;
54}();
55
56var EOIMarkerError = function EOIMarkerErrorClosure() {
57 function EOIMarkerError(message) {
58 this.message = message;
59 }
60
61 EOIMarkerError.prototype = new Error();
62 EOIMarkerError.prototype.name = 'EOIMarkerError';
63 EOIMarkerError.constructor = EOIMarkerError;
64 return EOIMarkerError;
65}();
66
67var JpegImage = function JpegImageClosure() {
68 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]);
69 var dctCos1 = 4017;
70 var dctSin1 = 799;
71 var dctCos3 = 3406;
72 var dctSin3 = 2276;
73 var dctCos6 = 1567;
74 var dctSin6 = 3784;
75 var dctSqrt2 = 5793;
76 var dctSqrt1d2 = 2896;
77
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
85 this._decodeTransform = decodeTransform;
86 this._colorTransform = colorTransform;
87 }
88
89 function buildHuffmanTable(codeLengths, values) {
90 var k = 0,
91 code = [],
92 i,
93 j,
94 length = 16;
95
96 while (length > 0 && !codeLengths[length - 1]) {
97 length--;
98 }
99
100 code.push({
101 children: [],
102 index: 0
103 });
104 var p = code[0],
105 q;
106
107 for (i = 0; i < length; i++) {
108 for (j = 0; j < codeLengths[i]; j++) {
109 p = code.pop();
110 p.children[p.index] = values[k];
111
112 while (p.index > 0) {
113 p = code.pop();
114 }
115
116 p.index++;
117 code.push(p);
118
119 while (code.length <= i) {
120 code.push(q = {
121 children: [],
122 index: 0
123 });
124 p.children[p.index] = q.children;
125 p = q;
126 }
127
128 k++;
129 }
130
131 if (i + 1 < length) {
132 code.push(q = {
133 children: [],
134 index: 0
135 });
136 p.children[p.index] = q.children;
137 p = q;
138 }
139 }
140
141 return code[0].children;
142 }
143
144 function getBlockBufferOffset(component, row, col) {
145 return 64 * ((component.blocksPerLine + 1) * row + col);
146 }
147
148 function decodeScan(data, offset, frame, components, resetInterval, spectralStart, spectralEnd, successivePrev, successive) {
149 var parseDNLMarker = arguments.length > 9 && arguments[9] !== undefined ? arguments[9] : false;
150 var mcusPerLine = frame.mcusPerLine;
151 var progressive = frame.progressive;
152 var startOffset = offset,
153 bitsData = 0,
154 bitsCount = 0;
155
156 function readBit() {
157 if (bitsCount > 0) {
158 bitsCount--;
159 return bitsData >> bitsCount & 1;
160 }
161
162 bitsData = data[offset++];
163
164 if (bitsData === 0xFF) {
165 var nextByte = data[offset++];
166
167 if (nextByte) {
168 if (nextByte === 0xDC && parseDNLMarker) {
169 offset += 2;
170 var scanLines = data[offset++] << 8 | data[offset++];
171
172 if (scanLines > 0 && scanLines !== frame.scanLines) {
173 throw new DNLMarkerError('Found DNL marker (0xFFDC) while parsing scan data', scanLines);
174 }
175 } else if (nextByte === 0xD9) {
176 throw new EOIMarkerError('Found EOI marker (0xFFD9) while parsing scan data');
177 }
178
179 throw new JpegError("unexpected marker ".concat((bitsData << 8 | nextByte).toString(16)));
180 }
181 }
182
183 bitsCount = 7;
184 return bitsData >>> 7;
185 }
186
187 function decodeHuffman(tree) {
188 var node = tree;
189
190 while (true) {
191 node = node[readBit()];
192
193 if (typeof node === 'number') {
194 return node;
195 }
196
197 if (_typeof(node) !== 'object') {
198 throw new JpegError('invalid huffman sequence');
199 }
200 }
201 }
202
203 function receive(length) {
204 var n = 0;
205
206 while (length > 0) {
207 n = n << 1 | readBit();
208 length--;
209 }
210
211 return n;
212 }
213
214 function receiveAndExtend(length) {
215 if (length === 1) {
216 return readBit() === 1 ? 1 : -1;
217 }
218
219 var n = receive(length);
220
221 if (n >= 1 << length - 1) {
222 return n;
223 }
224
225 return n + (-1 << length) + 1;
226 }
227
228 function decodeBaseline(component, offset) {
229 var t = decodeHuffman(component.huffmanTableDC);
230 var diff = t === 0 ? 0 : receiveAndExtend(t);
231 component.blockData[offset] = component.pred += diff;
232 var k = 1;
233
234 while (k < 64) {
235 var rs = decodeHuffman(component.huffmanTableAC);
236 var s = rs & 15,
237 r = rs >> 4;
238
239 if (s === 0) {
240 if (r < 15) {
241 break;
242 }
243
244 k += 16;
245 continue;
246 }
247
248 k += r;
249 var z = dctZigZag[k];
250 component.blockData[offset + z] = receiveAndExtend(s);
251 k++;
252 }
253 }
254
255 function decodeDCFirst(component, offset) {
256 var t = decodeHuffman(component.huffmanTableDC);
257 var diff = t === 0 ? 0 : receiveAndExtend(t) << successive;
258 component.blockData[offset] = component.pred += diff;
259 }
260
261 function decodeDCSuccessive(component, offset) {
262 component.blockData[offset] |= readBit() << successive;
263 }
264
265 var eobrun = 0;
266
267 function decodeACFirst(component, offset) {
268 if (eobrun > 0) {
269 eobrun--;
270 return;
271 }
272
273 var k = spectralStart,
274 e = spectralEnd;
275
276 while (k <= e) {
277 var rs = decodeHuffman(component.huffmanTableAC);
278 var s = rs & 15,
279 r = rs >> 4;
280
281 if (s === 0) {
282 if (r < 15) {
283 eobrun = receive(r) + (1 << r) - 1;
284 break;
285 }
286
287 k += 16;
288 continue;
289 }
290
291 k += r;
292 var z = dctZigZag[k];
293 component.blockData[offset + z] = receiveAndExtend(s) * (1 << successive);
294 k++;
295 }
296 }
297
298 var successiveACState = 0,
299 successiveACNextValue;
300
301 function decodeACSuccessive(component, offset) {
302 var k = spectralStart;
303 var e = spectralEnd;
304 var r = 0;
305 var s;
306 var rs;
307
308 while (k <= e) {
309 var offsetZ = offset + dctZigZag[k];
310 var sign = component.blockData[offsetZ] < 0 ? -1 : 1;
311
312 switch (successiveACState) {
313 case 0:
314 rs = decodeHuffman(component.huffmanTableAC);
315 s = rs & 15;
316 r = rs >> 4;
317
318 if (s === 0) {
319 if (r < 15) {
320 eobrun = receive(r) + (1 << r);
321 successiveACState = 4;
322 } else {
323 r = 16;
324 successiveACState = 1;
325 }
326 } else {
327 if (s !== 1) {
328 throw new JpegError('invalid ACn encoding');
329 }
330
331 successiveACNextValue = receiveAndExtend(s);
332 successiveACState = r ? 2 : 3;
333 }
334
335 continue;
336
337 case 1:
338 case 2:
339 if (component.blockData[offsetZ]) {
340 component.blockData[offsetZ] += sign * (readBit() << successive);
341 } else {
342 r--;
343
344 if (r === 0) {
345 successiveACState = successiveACState === 2 ? 3 : 0;
346 }
347 }
348
349 break;
350
351 case 3:
352 if (component.blockData[offsetZ]) {
353 component.blockData[offsetZ] += sign * (readBit() << successive);
354 } else {
355 component.blockData[offsetZ] = successiveACNextValue << successive;
356 successiveACState = 0;
357 }
358
359 break;
360
361 case 4:
362 if (component.blockData[offsetZ]) {
363 component.blockData[offsetZ] += sign * (readBit() << successive);
364 }
365
366 break;
367 }
368
369 k++;
370 }
371
372 if (successiveACState === 4) {
373 eobrun--;
374
375 if (eobrun === 0) {
376 successiveACState = 0;
377 }
378 }
379 }
380
381 function decodeMcu(component, decode, mcu, row, col) {
382 var mcuRow = mcu / mcusPerLine | 0;
383 var mcuCol = mcu % mcusPerLine;
384 var blockRow = mcuRow * component.v + row;
385 var blockCol = mcuCol * component.h + col;
386 var offset = getBlockBufferOffset(component, blockRow, blockCol);
387 decode(component, offset);
388 }
389
390 function decodeBlock(component, decode, mcu) {
391 var blockRow = mcu / component.blocksPerLine | 0;
392 var blockCol = mcu % component.blocksPerLine;
393 var offset = getBlockBufferOffset(component, blockRow, blockCol);
394 decode(component, offset);
395 }
396
397 var componentsLength = components.length;
398 var component, i, j, k, n;
399 var decodeFn;
400
401 if (progressive) {
402 if (spectralStart === 0) {
403 decodeFn = successivePrev === 0 ? decodeDCFirst : decodeDCSuccessive;
404 } else {
405 decodeFn = successivePrev === 0 ? decodeACFirst : decodeACSuccessive;
406 }
407 } else {
408 decodeFn = decodeBaseline;
409 }
410
411 var mcu = 0,
412 fileMarker;
413 var mcuExpected;
414
415 if (componentsLength === 1) {
416 mcuExpected = components[0].blocksPerLine * components[0].blocksPerColumn;
417 } else {
418 mcuExpected = mcusPerLine * frame.mcusPerColumn;
419 }
420
421 var h, v;
422
423 while (mcu < mcuExpected) {
424 var mcuToRead = resetInterval ? Math.min(mcuExpected - mcu, resetInterval) : mcuExpected;
425
426 for (i = 0; i < componentsLength; i++) {
427 components[i].pred = 0;
428 }
429
430 eobrun = 0;
431
432 if (componentsLength === 1) {
433 component = components[0];
434
435 for (n = 0; n < mcuToRead; n++) {
436 decodeBlock(component, decodeFn, mcu);
437 mcu++;
438 }
439 } else {
440 for (n = 0; n < mcuToRead; n++) {
441 for (i = 0; i < componentsLength; i++) {
442 component = components[i];
443 h = component.h;
444 v = component.v;
445
446 for (j = 0; j < v; j++) {
447 for (k = 0; k < h; k++) {
448 decodeMcu(component, decodeFn, mcu, j, k);
449 }
450 }
451 }
452
453 mcu++;
454 }
455 }
456
457 bitsCount = 0;
458 fileMarker = findNextFileMarker(data, offset);
459
460 if (fileMarker && fileMarker.invalid) {
461 (0, _util.warn)('decodeScan - unexpected MCU data, current marker is: ' + fileMarker.invalid);
462 offset = fileMarker.offset;
463 }
464
465 var marker = fileMarker && fileMarker.marker;
466
467 if (!marker || marker <= 0xFF00) {
468 throw new JpegError('marker was not found');
469 }
470
471 if (marker >= 0xFFD0 && marker <= 0xFFD7) {
472 offset += 2;
473 } else {
474 break;
475 }
476 }
477
478 fileMarker = findNextFileMarker(data, offset);
479
480 if (fileMarker && fileMarker.invalid) {
481 (0, _util.warn)('decodeScan - unexpected Scan data, current marker is: ' + fileMarker.invalid);
482 offset = fileMarker.offset;
483 }
484
485 return offset - startOffset;
486 }
487
488 function quantizeAndInverse(component, blockBufferOffset, p) {
489 var qt = component.quantizationTable,
490 blockData = component.blockData;
491 var v0, v1, v2, v3, v4, v5, v6, v7;
492 var p0, p1, p2, p3, p4, p5, p6, p7;
493 var t;
494
495 if (!qt) {
496 throw new JpegError('missing required Quantization Table.');
497 }
498
499 for (var row = 0; row < 64; row += 8) {
500 p0 = blockData[blockBufferOffset + row];
501 p1 = blockData[blockBufferOffset + row + 1];
502 p2 = blockData[blockBufferOffset + row + 2];
503 p3 = blockData[blockBufferOffset + row + 3];
504 p4 = blockData[blockBufferOffset + row + 4];
505 p5 = blockData[blockBufferOffset + row + 5];
506 p6 = blockData[blockBufferOffset + row + 6];
507 p7 = blockData[blockBufferOffset + row + 7];
508 p0 *= qt[row];
509
510 if ((p1 | p2 | p3 | p4 | p5 | p6 | p7) === 0) {
511 t = dctSqrt2 * p0 + 512 >> 10;
512 p[row] = t;
513 p[row + 1] = t;
514 p[row + 2] = t;
515 p[row + 3] = t;
516 p[row + 4] = t;
517 p[row + 5] = t;
518 p[row + 6] = t;
519 p[row + 7] = t;
520 continue;
521 }
522
523 p1 *= qt[row + 1];
524 p2 *= qt[row + 2];
525 p3 *= qt[row + 3];
526 p4 *= qt[row + 4];
527 p5 *= qt[row + 5];
528 p6 *= qt[row + 6];
529 p7 *= qt[row + 7];
530 v0 = dctSqrt2 * p0 + 128 >> 8;
531 v1 = dctSqrt2 * p4 + 128 >> 8;
532 v2 = p2;
533 v3 = p6;
534 v4 = dctSqrt1d2 * (p1 - p7) + 128 >> 8;
535 v7 = dctSqrt1d2 * (p1 + p7) + 128 >> 8;
536 v5 = p3 << 4;
537 v6 = p5 << 4;
538 v0 = v0 + v1 + 1 >> 1;
539 v1 = v0 - v1;
540 t = v2 * dctSin6 + v3 * dctCos6 + 128 >> 8;
541 v2 = v2 * dctCos6 - v3 * dctSin6 + 128 >> 8;
542 v3 = t;
543 v4 = v4 + v6 + 1 >> 1;
544 v6 = v4 - v6;
545 v7 = v7 + v5 + 1 >> 1;
546 v5 = v7 - v5;
547 v0 = v0 + v3 + 1 >> 1;
548 v3 = v0 - v3;
549 v1 = v1 + v2 + 1 >> 1;
550 v2 = v1 - v2;
551 t = v4 * dctSin3 + v7 * dctCos3 + 2048 >> 12;
552 v4 = v4 * dctCos3 - v7 * dctSin3 + 2048 >> 12;
553 v7 = t;
554 t = v5 * dctSin1 + v6 * dctCos1 + 2048 >> 12;
555 v5 = v5 * dctCos1 - v6 * dctSin1 + 2048 >> 12;
556 v6 = t;
557 p[row] = v0 + v7;
558 p[row + 7] = v0 - v7;
559 p[row + 1] = v1 + v6;
560 p[row + 6] = v1 - v6;
561 p[row + 2] = v2 + v5;
562 p[row + 5] = v2 - v5;
563 p[row + 3] = v3 + v4;
564 p[row + 4] = v3 - v4;
565 }
566
567 for (var col = 0; col < 8; ++col) {
568 p0 = p[col];
569 p1 = p[col + 8];
570 p2 = p[col + 16];
571 p3 = p[col + 24];
572 p4 = p[col + 32];
573 p5 = p[col + 40];
574 p6 = p[col + 48];
575 p7 = p[col + 56];
576
577 if ((p1 | p2 | p3 | p4 | p5 | p6 | p7) === 0) {
578 t = dctSqrt2 * p0 + 8192 >> 14;
579 t = t < -2040 ? 0 : t >= 2024 ? 255 : t + 2056 >> 4;
580 blockData[blockBufferOffset + col] = t;
581 blockData[blockBufferOffset + col + 8] = t;
582 blockData[blockBufferOffset + col + 16] = t;
583 blockData[blockBufferOffset + col + 24] = t;
584 blockData[blockBufferOffset + col + 32] = t;
585 blockData[blockBufferOffset + col + 40] = t;
586 blockData[blockBufferOffset + col + 48] = t;
587 blockData[blockBufferOffset + col + 56] = t;
588 continue;
589 }
590
591 v0 = dctSqrt2 * p0 + 2048 >> 12;
592 v1 = dctSqrt2 * p4 + 2048 >> 12;
593 v2 = p2;
594 v3 = p6;
595 v4 = dctSqrt1d2 * (p1 - p7) + 2048 >> 12;
596 v7 = dctSqrt1d2 * (p1 + p7) + 2048 >> 12;
597 v5 = p3;
598 v6 = p5;
599 v0 = (v0 + v1 + 1 >> 1) + 4112;
600 v1 = v0 - v1;
601 t = v2 * dctSin6 + v3 * dctCos6 + 2048 >> 12;
602 v2 = v2 * dctCos6 - v3 * dctSin6 + 2048 >> 12;
603 v3 = t;
604 v4 = v4 + v6 + 1 >> 1;
605 v6 = v4 - v6;
606 v7 = v7 + v5 + 1 >> 1;
607 v5 = v7 - v5;
608 v0 = v0 + v3 + 1 >> 1;
609 v3 = v0 - v3;
610 v1 = v1 + v2 + 1 >> 1;
611 v2 = v1 - v2;
612 t = v4 * dctSin3 + v7 * dctCos3 + 2048 >> 12;
613 v4 = v4 * dctCos3 - v7 * dctSin3 + 2048 >> 12;
614 v7 = t;
615 t = v5 * dctSin1 + v6 * dctCos1 + 2048 >> 12;
616 v5 = v5 * dctCos1 - v6 * dctSin1 + 2048 >> 12;
617 v6 = t;
618 p0 = v0 + v7;
619 p7 = v0 - v7;
620 p1 = v1 + v6;
621 p6 = v1 - v6;
622 p2 = v2 + v5;
623 p5 = v2 - v5;
624 p3 = v3 + v4;
625 p4 = v3 - v4;
626 p0 = p0 < 16 ? 0 : p0 >= 4080 ? 255 : p0 >> 4;
627 p1 = p1 < 16 ? 0 : p1 >= 4080 ? 255 : p1 >> 4;
628 p2 = p2 < 16 ? 0 : p2 >= 4080 ? 255 : p2 >> 4;
629 p3 = p3 < 16 ? 0 : p3 >= 4080 ? 255 : p3 >> 4;
630 p4 = p4 < 16 ? 0 : p4 >= 4080 ? 255 : p4 >> 4;
631 p5 = p5 < 16 ? 0 : p5 >= 4080 ? 255 : p5 >> 4;
632 p6 = p6 < 16 ? 0 : p6 >= 4080 ? 255 : p6 >> 4;
633 p7 = p7 < 16 ? 0 : p7 >= 4080 ? 255 : p7 >> 4;
634 blockData[blockBufferOffset + col] = p0;
635 blockData[blockBufferOffset + col + 8] = p1;
636 blockData[blockBufferOffset + col + 16] = p2;
637 blockData[blockBufferOffset + col + 24] = p3;
638 blockData[blockBufferOffset + col + 32] = p4;
639 blockData[blockBufferOffset + col + 40] = p5;
640 blockData[blockBufferOffset + col + 48] = p6;
641 blockData[blockBufferOffset + col + 56] = p7;
642 }
643 }
644
645 function buildComponentData(frame, component) {
646 var blocksPerLine = component.blocksPerLine;
647 var blocksPerColumn = component.blocksPerColumn;
648 var computationBuffer = new Int16Array(64);
649
650 for (var blockRow = 0; blockRow < blocksPerColumn; blockRow++) {
651 for (var blockCol = 0; blockCol < blocksPerLine; blockCol++) {
652 var offset = getBlockBufferOffset(component, blockRow, blockCol);
653 quantizeAndInverse(component, offset, computationBuffer);
654 }
655 }
656
657 return component.blockData;
658 }
659
660 function findNextFileMarker(data, currentPos) {
661 var startPos = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : currentPos;
662
663 function peekUint16(pos) {
664 return data[pos] << 8 | data[pos + 1];
665 }
666
667 var maxPos = data.length - 1;
668 var newPos = startPos < currentPos ? startPos : currentPos;
669
670 if (currentPos >= maxPos) {
671 return null;
672 }
673
674 var currentMarker = peekUint16(currentPos);
675
676 if (currentMarker >= 0xFFC0 && currentMarker <= 0xFFFE) {
677 return {
678 invalid: null,
679 marker: currentMarker,
680 offset: currentPos
681 };
682 }
683
684 var newMarker = peekUint16(newPos);
685
686 while (!(newMarker >= 0xFFC0 && newMarker <= 0xFFFE)) {
687 if (++newPos >= maxPos) {
688 return null;
689 }
690
691 newMarker = peekUint16(newPos);
692 }
693
694 return {
695 invalid: currentMarker.toString(16),
696 marker: newMarker,
697 offset: newPos
698 };
699 }
700
701 JpegImage.prototype = {
702 parse: function parse(data) {
703 var _ref2 = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {},
704 _ref2$dnlScanLines = _ref2.dnlScanLines,
705 dnlScanLines = _ref2$dnlScanLines === void 0 ? null : _ref2$dnlScanLines;
706
707 function readUint16() {
708 var value = data[offset] << 8 | data[offset + 1];
709 offset += 2;
710 return value;
711 }
712
713 function readDataBlock() {
714 var length = readUint16();
715 var endOffset = offset + length - 2;
716 var fileMarker = findNextFileMarker(data, endOffset, offset);
717
718 if (fileMarker && fileMarker.invalid) {
719 (0, _util.warn)('readDataBlock - incorrect length, current marker is: ' + fileMarker.invalid);
720 endOffset = fileMarker.offset;
721 }
722
723 var array = data.subarray(offset, endOffset);
724 offset += array.length;
725 return array;
726 }
727
728 function prepareComponents(frame) {
729 var mcusPerLine = Math.ceil(frame.samplesPerLine / 8 / frame.maxH);
730 var mcusPerColumn = Math.ceil(frame.scanLines / 8 / frame.maxV);
731
732 for (var i = 0; i < frame.components.length; i++) {
733 component = frame.components[i];
734 var blocksPerLine = Math.ceil(Math.ceil(frame.samplesPerLine / 8) * component.h / frame.maxH);
735 var blocksPerColumn = Math.ceil(Math.ceil(frame.scanLines / 8) * component.v / frame.maxV);
736 var blocksPerLineForMcu = mcusPerLine * component.h;
737 var blocksPerColumnForMcu = mcusPerColumn * component.v;
738 var blocksBufferSize = 64 * blocksPerColumnForMcu * (blocksPerLineForMcu + 1);
739 component.blockData = new Int16Array(blocksBufferSize);
740 component.blocksPerLine = blocksPerLine;
741 component.blocksPerColumn = blocksPerColumn;
742 }
743
744 frame.mcusPerLine = mcusPerLine;
745 frame.mcusPerColumn = mcusPerColumn;
746 }
747
748 var offset = 0;
749 var jfif = null;
750 var adobe = null;
751 var frame, resetInterval;
752 var numSOSMarkers = 0;
753 var quantizationTables = [];
754 var huffmanTablesAC = [],
755 huffmanTablesDC = [];
756 var fileMarker = readUint16();
757
758 if (fileMarker !== 0xFFD8) {
759 throw new JpegError('SOI not found');
760 }
761
762 fileMarker = readUint16();
763
764 markerLoop: while (fileMarker !== 0xFFD9) {
765 var i, j, l;
766
767 switch (fileMarker) {
768 case 0xFFE0:
769 case 0xFFE1:
770 case 0xFFE2:
771 case 0xFFE3:
772 case 0xFFE4:
773 case 0xFFE5:
774 case 0xFFE6:
775 case 0xFFE7:
776 case 0xFFE8:
777 case 0xFFE9:
778 case 0xFFEA:
779 case 0xFFEB:
780 case 0xFFEC:
781 case 0xFFED:
782 case 0xFFEE:
783 case 0xFFEF:
784 case 0xFFFE:
785 var appData = readDataBlock();
786
787 if (fileMarker === 0xFFE0) {
788 if (appData[0] === 0x4A && appData[1] === 0x46 && appData[2] === 0x49 && appData[3] === 0x46 && appData[4] === 0) {
789 jfif = {
790 version: {
791 major: appData[5],
792 minor: appData[6]
793 },
794 densityUnits: appData[7],
795 xDensity: appData[8] << 8 | appData[9],
796 yDensity: appData[10] << 8 | appData[11],
797 thumbWidth: appData[12],
798 thumbHeight: appData[13],
799 thumbData: appData.subarray(14, 14 + 3 * appData[12] * appData[13])
800 };
801 }
802 }
803
804 if (fileMarker === 0xFFEE) {
805 if (appData[0] === 0x41 && appData[1] === 0x64 && appData[2] === 0x6F && appData[3] === 0x62 && appData[4] === 0x65) {
806 adobe = {
807 version: appData[5] << 8 | appData[6],
808 flags0: appData[7] << 8 | appData[8],
809 flags1: appData[9] << 8 | appData[10],
810 transformCode: appData[11]
811 };
812 }
813 }
814
815 break;
816
817 case 0xFFDB:
818 var quantizationTablesLength = readUint16();
819 var quantizationTablesEnd = quantizationTablesLength + offset - 2;
820 var z;
821
822 while (offset < quantizationTablesEnd) {
823 var quantizationTableSpec = data[offset++];
824 var tableData = new Uint16Array(64);
825
826 if (quantizationTableSpec >> 4 === 0) {
827 for (j = 0; j < 64; j++) {
828 z = dctZigZag[j];
829 tableData[z] = data[offset++];
830 }
831 } else if (quantizationTableSpec >> 4 === 1) {
832 for (j = 0; j < 64; j++) {
833 z = dctZigZag[j];
834 tableData[z] = readUint16();
835 }
836 } else {
837 throw new JpegError('DQT - invalid table spec');
838 }
839
840 quantizationTables[quantizationTableSpec & 15] = tableData;
841 }
842
843 break;
844
845 case 0xFFC0:
846 case 0xFFC1:
847 case 0xFFC2:
848 if (frame) {
849 throw new JpegError('Only single frame JPEGs supported');
850 }
851
852 readUint16();
853 frame = {};
854 frame.extended = fileMarker === 0xFFC1;
855 frame.progressive = fileMarker === 0xFFC2;
856 frame.precision = data[offset++];
857 var sofScanLines = readUint16();
858 frame.scanLines = dnlScanLines || sofScanLines;
859 frame.samplesPerLine = readUint16();
860 frame.components = [];
861 frame.componentIds = {};
862 var componentsCount = data[offset++],
863 componentId;
864 var maxH = 0,
865 maxV = 0;
866
867 for (i = 0; i < componentsCount; i++) {
868 componentId = data[offset];
869 var h = data[offset + 1] >> 4;
870 var v = data[offset + 1] & 15;
871
872 if (maxH < h) {
873 maxH = h;
874 }
875
876 if (maxV < v) {
877 maxV = v;
878 }
879
880 var qId = data[offset + 2];
881 l = frame.components.push({
882 h: h,
883 v: v,
884 quantizationId: qId,
885 quantizationTable: null
886 });
887 frame.componentIds[componentId] = l - 1;
888 offset += 3;
889 }
890
891 frame.maxH = maxH;
892 frame.maxV = maxV;
893 prepareComponents(frame);
894 break;
895
896 case 0xFFC4:
897 var huffmanLength = readUint16();
898
899 for (i = 2; i < huffmanLength;) {
900 var huffmanTableSpec = data[offset++];
901 var codeLengths = new Uint8Array(16);
902 var codeLengthSum = 0;
903
904 for (j = 0; j < 16; j++, offset++) {
905 codeLengthSum += codeLengths[j] = data[offset];
906 }
907
908 var huffmanValues = new Uint8Array(codeLengthSum);
909
910 for (j = 0; j < codeLengthSum; j++, offset++) {
911 huffmanValues[j] = data[offset];
912 }
913
914 i += 17 + codeLengthSum;
915 (huffmanTableSpec >> 4 === 0 ? huffmanTablesDC : huffmanTablesAC)[huffmanTableSpec & 15] = buildHuffmanTable(codeLengths, huffmanValues);
916 }
917
918 break;
919
920 case 0xFFDD:
921 readUint16();
922 resetInterval = readUint16();
923 break;
924
925 case 0xFFDA:
926 var parseDNLMarker = ++numSOSMarkers === 1 && !dnlScanLines;
927 readUint16();
928 var selectorsCount = data[offset++];
929 var components = [],
930 component;
931
932 for (i = 0; i < selectorsCount; i++) {
933 var componentIndex = frame.componentIds[data[offset++]];
934 component = frame.components[componentIndex];
935 var tableSpec = data[offset++];
936 component.huffmanTableDC = huffmanTablesDC[tableSpec >> 4];
937 component.huffmanTableAC = huffmanTablesAC[tableSpec & 15];
938 components.push(component);
939 }
940
941 var spectralStart = data[offset++];
942 var spectralEnd = data[offset++];
943 var successiveApproximation = data[offset++];
944
945 try {
946 var processed = decodeScan(data, offset, frame, components, resetInterval, spectralStart, spectralEnd, successiveApproximation >> 4, successiveApproximation & 15, parseDNLMarker);
947 offset += processed;
948 } catch (ex) {
949 if (ex instanceof DNLMarkerError) {
950 (0, _util.warn)("".concat(ex.message, " -- attempting to re-parse the JPEG image."));
951 return this.parse(data, {
952 dnlScanLines: ex.scanLines
953 });
954 } else if (ex instanceof EOIMarkerError) {
955 (0, _util.warn)("".concat(ex.message, " -- ignoring the rest of the image data."));
956 break markerLoop;
957 }
958
959 throw ex;
960 }
961
962 break;
963
964 case 0xFFDC:
965 offset += 4;
966 break;
967
968 case 0xFFFF:
969 if (data[offset] !== 0xFF) {
970 offset--;
971 }
972
973 break;
974
975 default:
976 if (data[offset - 3] === 0xFF && data[offset - 2] >= 0xC0 && data[offset - 2] <= 0xFE) {
977 offset -= 3;
978 break;
979 }
980
981 var nextFileMarker = findNextFileMarker(data, offset - 2);
982
983 if (nextFileMarker && nextFileMarker.invalid) {
984 (0, _util.warn)('JpegImage.parse - unexpected data, current marker is: ' + nextFileMarker.invalid);
985 offset = nextFileMarker.offset;
986 break;
987 }
988
989 throw new JpegError('unknown marker ' + fileMarker.toString(16));
990 }
991
992 fileMarker = readUint16();
993 }
994
995 this.width = frame.samplesPerLine;
996 this.height = frame.scanLines;
997 this.jfif = jfif;
998 this.adobe = adobe;
999 this.components = [];
1000
1001 for (i = 0; i < frame.components.length; i++) {
1002 component = frame.components[i];
1003 var quantizationTable = quantizationTables[component.quantizationId];
1004
1005 if (quantizationTable) {
1006 component.quantizationTable = quantizationTable;
1007 }
1008
1009 this.components.push({
1010 output: buildComponentData(frame, component),
1011 scaleX: component.h / frame.maxH,
1012 scaleY: component.v / frame.maxV,
1013 blocksPerLine: component.blocksPerLine,
1014 blocksPerColumn: component.blocksPerColumn
1015 });
1016 }
1017
1018 this.numComponents = this.components.length;
1019 },
1020 _getLinearizedBlockData: function _getLinearizedBlockData(width, height) {
1021 var isSourcePDF = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : false;
1022 var scaleX = this.width / width,
1023 scaleY = this.height / height;
1024 var component, componentScaleX, componentScaleY, blocksPerScanline;
1025 var x, y, i, j, k;
1026 var index;
1027 var offset = 0;
1028 var output;
1029 var numComponents = this.components.length;
1030 var dataLength = width * height * numComponents;
1031 var data = new Uint8ClampedArray(dataLength);
1032 var xScaleBlockOffset = new Uint32Array(width);
1033 var mask3LSB = 0xfffffff8;
1034
1035 for (i = 0; i < numComponents; i++) {
1036 component = this.components[i];
1037 componentScaleX = component.scaleX * scaleX;
1038 componentScaleY = component.scaleY * scaleY;
1039 offset = i;
1040 output = component.output;
1041 blocksPerScanline = component.blocksPerLine + 1 << 3;
1042
1043 for (x = 0; x < width; x++) {
1044 j = 0 | x * componentScaleX;
1045 xScaleBlockOffset[x] = (j & mask3LSB) << 3 | j & 7;
1046 }
1047
1048 for (y = 0; y < height; y++) {
1049 j = 0 | y * componentScaleY;
1050 index = blocksPerScanline * (j & mask3LSB) | (j & 7) << 3;
1051
1052 for (x = 0; x < width; x++) {
1053 data[offset] = output[index + xScaleBlockOffset[x]];
1054 offset += numComponents;
1055 }
1056 }
1057 }
1058
1059 var transform = this._decodeTransform;
1060
1061 if (!isSourcePDF && numComponents === 4 && !transform) {
1062 transform = new Int32Array([-256, 255, -256, 255, -256, 255, -256, 255]);
1063 }
1064
1065 if (transform) {
1066 for (i = 0; i < dataLength;) {
1067 for (j = 0, k = 0; j < numComponents; j++, i++, k += 2) {
1068 data[i] = (data[i] * transform[k] >> 8) + transform[k + 1];
1069 }
1070 }
1071 }
1072
1073 return data;
1074 },
1075
1076 get _isColorConversionNeeded() {
1077 if (this.adobe) {
1078 return !!this.adobe.transformCode;
1079 }
1080
1081 if (this.numComponents === 3) {
1082 if (this._colorTransform === 0) {
1083 return false;
1084 }
1085
1086 return true;
1087 }
1088
1089 if (this._colorTransform === 1) {
1090 return true;
1091 }
1092
1093 return false;
1094 },
1095
1096 _convertYccToRgb: function convertYccToRgb(data) {
1097 var Y, Cb, Cr;
1098
1099 for (var i = 0, length = data.length; i < length; i += 3) {
1100 Y = data[i];
1101 Cb = data[i + 1];
1102 Cr = data[i + 2];
1103 data[i] = Y - 179.456 + 1.402 * Cr;
1104 data[i + 1] = Y + 135.459 - 0.344 * Cb - 0.714 * Cr;
1105 data[i + 2] = Y - 226.816 + 1.772 * Cb;
1106 }
1107
1108 return data;
1109 },
1110 _convertYcckToRgb: function convertYcckToRgb(data) {
1111 var Y, Cb, Cr, k;
1112 var offset = 0;
1113
1114 for (var i = 0, length = data.length; i < length; i += 4) {
1115 Y = data[i];
1116 Cb = data[i + 1];
1117 Cr = data[i + 2];
1118 k = data[i + 3];
1119 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);
1120 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);
1121 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);
1122 }
1123
1124 return data.subarray(0, offset);
1125 },
1126 _convertYcckToCmyk: function convertYcckToCmyk(data) {
1127 var Y, Cb, Cr;
1128
1129 for (var i = 0, length = data.length; i < length; i += 4) {
1130 Y = data[i];
1131 Cb = data[i + 1];
1132 Cr = data[i + 2];
1133 data[i] = 434.456 - Y - 1.402 * Cr;
1134 data[i + 1] = 119.541 - Y + 0.344 * Cb + 0.714 * Cr;
1135 data[i + 2] = 481.816 - Y - 1.772 * Cb;
1136 }
1137
1138 return data;
1139 },
1140 _convertCmykToRgb: function convertCmykToRgb(data) {
1141 var c, m, y, k;
1142 var offset = 0;
1143 var scale = 1 / 255;
1144
1145 for (var i = 0, length = data.length; i < length; i += 4) {
1146 c = data[i] * scale;
1147 m = data[i + 1] * scale;
1148 y = data[i + 2] * scale;
1149 k = data[i + 3] * scale;
1150 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);
1151 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);
1152 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);
1153 }
1154
1155 return data.subarray(0, offset);
1156 },
1157 getData: function getData(_ref3) {
1158 var width = _ref3.width,
1159 height = _ref3.height,
1160 _ref3$forceRGB = _ref3.forceRGB,
1161 forceRGB = _ref3$forceRGB === void 0 ? false : _ref3$forceRGB,
1162 _ref3$isSourcePDF = _ref3.isSourcePDF,
1163 isSourcePDF = _ref3$isSourcePDF === void 0 ? false : _ref3$isSourcePDF;
1164
1165 if (this.numComponents > 4) {
1166 throw new JpegError('Unsupported color mode');
1167 }
1168
1169 var data = this._getLinearizedBlockData(width, height, isSourcePDF);
1170
1171 if (this.numComponents === 1 && forceRGB) {
1172 var dataLength = data.length;
1173 var rgbData = new Uint8ClampedArray(dataLength * 3);
1174 var offset = 0;
1175
1176 for (var i = 0; i < dataLength; i++) {
1177 var grayColor = data[i];
1178 rgbData[offset++] = grayColor;
1179 rgbData[offset++] = grayColor;
1180 rgbData[offset++] = grayColor;
1181 }
1182
1183 return rgbData;
1184 } else if (this.numComponents === 3 && this._isColorConversionNeeded) {
1185 return this._convertYccToRgb(data);
1186 } else if (this.numComponents === 4) {
1187 if (this._isColorConversionNeeded) {
1188 if (forceRGB) {
1189 return this._convertYcckToRgb(data);
1190 }
1191
1192 return this._convertYcckToCmyk(data);
1193 } else if (forceRGB) {
1194 return this._convertCmykToRgb(data);
1195 }
1196 }
1197
1198 return data;
1199 }
1200 };
1201 return JpegImage;
1202}();
1203
1204exports.JpegImage = JpegImage;
\No newline at end of file