mirror of
https://gitee.com/onvia/ccc-tnt-psd2ui
synced 2024-12-29 13:07:43 +00:00
1024 lines
146 KiB
JavaScript
1024 lines
146 KiB
JavaScript
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"use strict";
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// based on https://github.com/jpeg-js/jpeg-js
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/*
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Copyright 2011 notmasteryet
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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Object.defineProperty(exports, "__esModule", { value: true });
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exports.decodeJpeg = void 0;
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var dctZigZag = new Int32Array([
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0,
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1, 8,
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16, 9, 2,
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3, 10, 17, 24,
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32, 25, 18, 11, 4,
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5, 12, 19, 26, 33, 40,
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48, 41, 34, 27, 20, 13, 6,
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7, 14, 21, 28, 35, 42, 49, 56,
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57, 50, 43, 36, 29, 22, 15,
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23, 30, 37, 44, 51, 58,
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59, 52, 45, 38, 31,
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39, 46, 53, 60,
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61, 54, 47,
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55, 62,
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63
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]);
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var dctCos1 = 4017; // cos(pi/16)
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var dctSin1 = 799; // sin(pi/16)
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var dctCos3 = 3406; // cos(3*pi/16)
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var dctSin3 = 2276; // sin(3*pi/16)
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var dctCos6 = 1567; // cos(6*pi/16)
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var dctSin6 = 3784; // sin(6*pi/16)
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var dctSqrt2 = 5793; // sqrt(2)
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var dctSqrt1d2 = 2896; // sqrt(2) / 2
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var maxResolutionInMP = 100; // Don't decode more than 100 megapixels
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var maxMemoryUsageBytes = 64 * 1024 * 1024; // Don't decode if memory footprint is more than 64MB
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var totalBytesAllocated = 0; // avoid unexpected OOMs from untrusted content.
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function requestMemoryAllocation(increaseAmount) {
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var totalMemoryImpactBytes = totalBytesAllocated + increaseAmount;
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if (totalMemoryImpactBytes > maxMemoryUsageBytes) {
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var exceededAmount = Math.ceil((totalMemoryImpactBytes - maxMemoryUsageBytes) / 1024 / 1024);
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throw new Error("Max memory limit exceeded by at least ".concat(exceededAmount, "MB"));
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}
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totalBytesAllocated = totalMemoryImpactBytes;
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}
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function buildHuffmanTable(codeLengths, values) {
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var length = 16;
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while (length > 0 && !codeLengths[length - 1])
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length--;
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var code = [{ children: [], index: 0 }];
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var k = 0;
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var p = code[0];
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for (var i = 0; i < length; i++) {
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for (var j = 0; j < codeLengths[i]; j++) {
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p = code.pop();
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p.children[p.index] = values[k];
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while (p.index > 0) {
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if (code.length === 0)
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throw new Error('Could not recreate Huffman Table');
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p = code.pop();
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}
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p.index++;
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code.push(p);
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while (code.length <= i) {
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var q = { children: [], index: 0 };
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code.push(q);
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p.children[p.index] = q.children;
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p = q;
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}
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k++;
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}
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if (i + 1 < length) {
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// p here points to last code
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var q = { children: [], index: 0 };
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code.push(q);
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p.children[p.index] = q.children;
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p = q;
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}
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}
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return code[0].children;
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}
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function decodeScan(data, offset, frame, components, resetInterval, spectralStart, spectralEnd, successivePrev, successive) {
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var mcusPerLine = frame.mcusPerLine;
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var progressive = frame.progressive;
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var startOffset = offset;
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var bitsData = 0;
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var bitsCount = 0;
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function readBit() {
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if (bitsCount > 0) {
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bitsCount--;
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return (bitsData >> bitsCount) & 1;
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}
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bitsData = data[offset++];
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if (bitsData == 0xFF) {
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var nextByte = data[offset++];
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if (nextByte)
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throw new Error("unexpected marker: ".concat(((bitsData << 8) | nextByte).toString(16)));
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// unstuff 0
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}
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bitsCount = 7;
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return bitsData >>> 7;
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}
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function decodeHuffman(tree) {
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var node = tree;
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while (true) {
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node = node[readBit()];
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if (typeof node === 'number')
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return node;
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if (node === undefined)
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throw new Error('invalid huffman sequence');
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}
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}
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function receive(length) {
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var n = 0;
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while (length > 0) {
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n = (n << 1) | readBit();
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length--;
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}
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return n;
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}
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function receiveAndExtend(length) {
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var n = receive(length);
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if (n >= 1 << (length - 1))
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return n;
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return n + (-1 << length) + 1;
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}
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function decodeBaseline(component, zz) {
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var t = decodeHuffman(component.huffmanTableDC);
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var diff = t === 0 ? 0 : receiveAndExtend(t);
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zz[0] = (component.pred += diff);
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var k = 1;
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while (k < 64) {
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var rs = decodeHuffman(component.huffmanTableAC);
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var s = rs & 15;
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var r = rs >> 4;
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if (s === 0) {
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if (r < 15)
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break;
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k += 16;
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continue;
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}
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k += r;
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var z = dctZigZag[k];
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zz[z] = receiveAndExtend(s);
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k++;
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}
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}
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function decodeDCFirst(component, zz) {
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var t = decodeHuffman(component.huffmanTableDC);
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var diff = t === 0 ? 0 : (receiveAndExtend(t) << successive);
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zz[0] = (component.pred += diff);
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}
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function decodeDCSuccessive(_component, zz) {
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zz[0] |= readBit() << successive;
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}
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var eobrun = 0;
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function decodeACFirst(component, zz) {
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if (eobrun > 0) {
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eobrun--;
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return;
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}
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var k = spectralStart, e = spectralEnd;
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while (k <= e) {
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var rs = decodeHuffman(component.huffmanTableAC);
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var s = rs & 15;
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var r = rs >> 4;
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if (s === 0) {
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if (r < 15) {
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eobrun = receive(r) + (1 << r) - 1;
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break;
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}
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k += 16;
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continue;
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}
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k += r;
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var z = dctZigZag[k];
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zz[z] = receiveAndExtend(s) * (1 << successive);
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k++;
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}
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}
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var successiveACState = 0;
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var successiveACNextValue = 0;
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function decodeACSuccessive(component, zz) {
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var k = spectralStart;
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var e = spectralEnd;
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var r = 0;
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while (k <= e) {
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var z = dctZigZag[k];
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var direction = zz[z] < 0 ? -1 : 1;
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switch (successiveACState) {
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case 0: // initial state
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var rs = decodeHuffman(component.huffmanTableAC);
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var s = rs & 15;
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r = rs >> 4; // this was new variable in old code
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if (s === 0) {
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if (r < 15) {
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eobrun = receive(r) + (1 << r);
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successiveACState = 4;
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}
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else {
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r = 16;
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successiveACState = 1;
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}
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}
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else {
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if (s !== 1)
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throw new Error('invalid ACn encoding');
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successiveACNextValue = receiveAndExtend(s);
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successiveACState = r ? 2 : 3;
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}
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continue;
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case 1: // skipping r zero items
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case 2:
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if (zz[z]) {
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zz[z] += (readBit() << successive) * direction;
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}
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else {
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r--;
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if (r === 0)
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successiveACState = successiveACState == 2 ? 3 : 0;
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}
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break;
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case 3: // set value for a zero item
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if (zz[z]) {
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zz[z] += (readBit() << successive) * direction;
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}
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else {
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zz[z] = successiveACNextValue << successive;
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successiveACState = 0;
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}
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break;
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case 4: // eob
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if (zz[z]) {
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zz[z] += (readBit() << successive) * direction;
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}
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break;
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}
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k++;
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}
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if (successiveACState === 4) {
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eobrun--;
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if (eobrun === 0)
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successiveACState = 0;
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}
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}
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function decodeMcu(component, decode, mcu, row, col) {
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var mcuRow = (mcu / mcusPerLine) | 0;
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var mcuCol = mcu % mcusPerLine;
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var blockRow = mcuRow * component.v + row;
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var blockCol = mcuCol * component.h + col;
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// If the block is missing, just skip it.
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if (component.blocks[blockRow] === undefined)
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return;
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decode(component, component.blocks[blockRow][blockCol]);
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}
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function decodeBlock(component, decode, mcu) {
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var blockRow = (mcu / component.blocksPerLine) | 0;
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var blockCol = mcu % component.blocksPerLine;
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// If the block is missing, just skip it.
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if (component.blocks[blockRow] === undefined)
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return;
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decode(component, component.blocks[blockRow][blockCol]);
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}
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var componentsLength = components.length;
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var component;
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var decodeFn;
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if (progressive) {
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if (spectralStart === 0) {
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decodeFn = successivePrev === 0 ? decodeDCFirst : decodeDCSuccessive;
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}
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else {
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decodeFn = successivePrev === 0 ? decodeACFirst : decodeACSuccessive;
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}
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}
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else {
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decodeFn = decodeBaseline;
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}
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var mcu = 0;
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var mcuExpected;
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if (componentsLength == 1) {
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mcuExpected = components[0].blocksPerLine * components[0].blocksPerColumn;
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}
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else {
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mcuExpected = mcusPerLine * frame.mcusPerColumn;
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}
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if (!resetInterval)
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resetInterval = mcuExpected;
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var h;
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var v;
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var marker;
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while (mcu < mcuExpected) {
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// reset interval stuff
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for (var i = 0; i < componentsLength; i++)
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components[i].pred = 0;
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eobrun = 0;
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if (componentsLength == 1) {
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component = components[0];
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for (var n = 0; n < resetInterval; n++) {
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decodeBlock(component, decodeFn, mcu);
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mcu++;
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}
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}
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else {
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for (var n = 0; n < resetInterval; n++) {
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for (var i = 0; i < componentsLength; i++) {
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component = components[i];
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h = component.h;
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v = component.v;
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for (var j = 0; j < v; j++) {
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for (var k = 0; k < h; k++) {
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decodeMcu(component, decodeFn, mcu, j, k);
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}
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}
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}
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mcu++;
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// If we've reached our expected MCU's, stop decoding
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if (mcu === mcuExpected)
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break;
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}
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}
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if (mcu === mcuExpected) {
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// Skip trailing bytes at the end of the scan - until we reach the next marker
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do {
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if (data[offset] === 0xFF) {
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if (data[offset + 1] !== 0x00) {
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break;
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}
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}
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offset += 1;
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} while (offset < data.length - 2);
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}
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// find marker
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bitsCount = 0;
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marker = (data[offset] << 8) | data[offset + 1];
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if (marker < 0xFF00)
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throw new Error('marker was not found');
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if (marker >= 0xFFD0 && marker <= 0xFFD7) { // RSTx
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offset += 2;
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}
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else {
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break;
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}
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}
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return offset - startOffset;
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}
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function buildComponentData(component) {
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var lines = [];
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var blocksPerLine = component.blocksPerLine;
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var blocksPerColumn = component.blocksPerColumn;
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var samplesPerLine = blocksPerLine << 3;
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// Only 1 used per invocation of this function and garbage collected after invocation, so no need to account for its memory footprint.
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var R = new Int32Array(64);
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var r = new Uint8Array(64);
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// A port of poppler's IDCT method which in turn is taken from:
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// Christoph Loeffler, Adriaan Ligtenberg, George S. Moschytz,
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// "Practical Fast 1-D DCT Algorithms with 11 Multiplications",
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// IEEE Intl. Conf. on Acoustics, Speech & Signal Processing, 1989,
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// 988-991.
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function quantizeAndInverse(zz, dataOut, dataIn) {
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var qt = component.quantizationTable;
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var p = dataIn;
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// dequant
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|
|
for (var i = 0; i < 64; i++) {
|
||
|
|
p[i] = zz[i] * qt[i];
|
||
|
|
}
|
||
|
|
// inverse DCT on rows
|
||
|
|
for (var i = 0; i < 8; ++i) {
|
||
|
|
var row = 8 * i;
|
||
|
|
// check for all-zero AC coefficients
|
||
|
|
if (p[1 + row] == 0 && p[2 + row] == 0 && p[3 + row] == 0 &&
|
||
|
|
p[4 + row] == 0 && p[5 + row] == 0 && p[6 + row] == 0 &&
|
||
|
|
p[7 + row] == 0) {
|
||
|
|
var t_1 = (dctSqrt2 * p[0 + row] + 512) >> 10;
|
||
|
|
p[0 + row] = t_1;
|
||
|
|
p[1 + row] = t_1;
|
||
|
|
p[2 + row] = t_1;
|
||
|
|
p[3 + row] = t_1;
|
||
|
|
p[4 + row] = t_1;
|
||
|
|
p[5 + row] = t_1;
|
||
|
|
p[6 + row] = t_1;
|
||
|
|
p[7 + row] = t_1;
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
// stage 4
|
||
|
|
var v0 = (dctSqrt2 * p[0 + row] + 128) >> 8;
|
||
|
|
var v1 = (dctSqrt2 * p[4 + row] + 128) >> 8;
|
||
|
|
var v2 = p[2 + row];
|
||
|
|
var v3 = p[6 + row];
|
||
|
|
var v4 = (dctSqrt1d2 * (p[1 + row] - p[7 + row]) + 128) >> 8;
|
||
|
|
var v7 = (dctSqrt1d2 * (p[1 + row] + p[7 + row]) + 128) >> 8;
|
||
|
|
var v5 = p[3 + row] << 4;
|
||
|
|
var v6 = p[5 + row] << 4;
|
||
|
|
// stage 3
|
||
|
|
var t = (v0 - v1 + 1) >> 1;
|
||
|
|
v0 = (v0 + v1 + 1) >> 1;
|
||
|
|
v1 = t;
|
||
|
|
t = (v2 * dctSin6 + v3 * dctCos6 + 128) >> 8;
|
||
|
|
v2 = (v2 * dctCos6 - v3 * dctSin6 + 128) >> 8;
|
||
|
|
v3 = t;
|
||
|
|
t = (v4 - v6 + 1) >> 1;
|
||
|
|
v4 = (v4 + v6 + 1) >> 1;
|
||
|
|
v6 = t;
|
||
|
|
t = (v7 + v5 + 1) >> 1;
|
||
|
|
v5 = (v7 - v5 + 1) >> 1;
|
||
|
|
v7 = t;
|
||
|
|
// stage 2
|
||
|
|
t = (v0 - v3 + 1) >> 1;
|
||
|
|
v0 = (v0 + v3 + 1) >> 1;
|
||
|
|
v3 = t;
|
||
|
|
t = (v1 - v2 + 1) >> 1;
|
||
|
|
v1 = (v1 + v2 + 1) >> 1;
|
||
|
|
v2 = t;
|
||
|
|
t = (v4 * dctSin3 + v7 * dctCos3 + 2048) >> 12;
|
||
|
|
v4 = (v4 * dctCos3 - v7 * dctSin3 + 2048) >> 12;
|
||
|
|
v7 = t;
|
||
|
|
t = (v5 * dctSin1 + v6 * dctCos1 + 2048) >> 12;
|
||
|
|
v5 = (v5 * dctCos1 - v6 * dctSin1 + 2048) >> 12;
|
||
|
|
v6 = t;
|
||
|
|
// stage 1
|
||
|
|
p[0 + row] = v0 + v7;
|
||
|
|
p[7 + row] = v0 - v7;
|
||
|
|
p[1 + row] = v1 + v6;
|
||
|
|
p[6 + row] = v1 - v6;
|
||
|
|
p[2 + row] = v2 + v5;
|
||
|
|
p[5 + row] = v2 - v5;
|
||
|
|
p[3 + row] = v3 + v4;
|
||
|
|
p[4 + row] = v3 - v4;
|
||
|
|
}
|
||
|
|
// inverse DCT on columns
|
||
|
|
for (var i = 0; i < 8; ++i) {
|
||
|
|
var col = i;
|
||
|
|
// check for all-zero AC coefficients
|
||
|
|
if (p[1 * 8 + col] == 0 && p[2 * 8 + col] == 0 && p[3 * 8 + col] == 0 &&
|
||
|
|
p[4 * 8 + col] == 0 && p[5 * 8 + col] == 0 && p[6 * 8 + col] == 0 &&
|
||
|
|
p[7 * 8 + col] == 0) {
|
||
|
|
var t_2 = (dctSqrt2 * dataIn[i + 0] + 8192) >> 14;
|
||
|
|
p[0 * 8 + col] = t_2;
|
||
|
|
p[1 * 8 + col] = t_2;
|
||
|
|
p[2 * 8 + col] = t_2;
|
||
|
|
p[3 * 8 + col] = t_2;
|
||
|
|
p[4 * 8 + col] = t_2;
|
||
|
|
p[5 * 8 + col] = t_2;
|
||
|
|
p[6 * 8 + col] = t_2;
|
||
|
|
p[7 * 8 + col] = t_2;
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
// stage 4
|
||
|
|
var v0 = (dctSqrt2 * p[0 * 8 + col] + 2048) >> 12;
|
||
|
|
var v1 = (dctSqrt2 * p[4 * 8 + col] + 2048) >> 12;
|
||
|
|
var v2 = p[2 * 8 + col];
|
||
|
|
var v3 = p[6 * 8 + col];
|
||
|
|
var v4 = (dctSqrt1d2 * (p[1 * 8 + col] - p[7 * 8 + col]) + 2048) >> 12;
|
||
|
|
var v7 = (dctSqrt1d2 * (p[1 * 8 + col] + p[7 * 8 + col]) + 2048) >> 12;
|
||
|
|
var v5 = p[3 * 8 + col];
|
||
|
|
var v6 = p[5 * 8 + col];
|
||
|
|
// stage 3
|
||
|
|
var t = (v0 - v1 + 1) >> 1;
|
||
|
|
v0 = (v0 + v1 + 1) >> 1;
|
||
|
|
v1 = t;
|
||
|
|
t = (v2 * dctSin6 + v3 * dctCos6 + 2048) >> 12;
|
||
|
|
v2 = (v2 * dctCos6 - v3 * dctSin6 + 2048) >> 12;
|
||
|
|
v3 = t;
|
||
|
|
t = (v4 - v6 + 1) >> 1;
|
||
|
|
v4 = (v4 + v6 + 1) >> 1;
|
||
|
|
v6 = t;
|
||
|
|
t = (v7 + v5 + 1) >> 1;
|
||
|
|
v5 = (v7 - v5 + 1) >> 1;
|
||
|
|
v7 = t;
|
||
|
|
// stage 2
|
||
|
|
t = (v0 - v3 + 1) >> 1;
|
||
|
|
v0 = (v0 + v3 + 1) >> 1;
|
||
|
|
v3 = t;
|
||
|
|
t = (v1 - v2 + 1) >> 1;
|
||
|
|
v1 = (v1 + v2 + 1) >> 1;
|
||
|
|
v2 = t;
|
||
|
|
t = (v4 * dctSin3 + v7 * dctCos3 + 2048) >> 12;
|
||
|
|
v4 = (v4 * dctCos3 - v7 * dctSin3 + 2048) >> 12;
|
||
|
|
v7 = t;
|
||
|
|
t = (v5 * dctSin1 + v6 * dctCos1 + 2048) >> 12;
|
||
|
|
v5 = (v5 * dctCos1 - v6 * dctSin1 + 2048) >> 12;
|
||
|
|
v6 = t;
|
||
|
|
// stage 1
|
||
|
|
p[0 * 8 + col] = v0 + v7;
|
||
|
|
p[7 * 8 + col] = v0 - v7;
|
||
|
|
p[1 * 8 + col] = v1 + v6;
|
||
|
|
p[6 * 8 + col] = v1 - v6;
|
||
|
|
p[2 * 8 + col] = v2 + v5;
|
||
|
|
p[5 * 8 + col] = v2 - v5;
|
||
|
|
p[3 * 8 + col] = v3 + v4;
|
||
|
|
p[4 * 8 + col] = v3 - v4;
|
||
|
|
}
|
||
|
|
// convert to 8-bit integers
|
||
|
|
for (var i = 0; i < 64; ++i) {
|
||
|
|
var sample = 128 + ((p[i] + 8) >> 4);
|
||
|
|
dataOut[i] = sample < 0 ? 0 : sample > 0xFF ? 0xFF : sample;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
requestMemoryAllocation(samplesPerLine * blocksPerColumn * 8);
|
||
|
|
for (var blockRow = 0; blockRow < blocksPerColumn; blockRow++) {
|
||
|
|
var scanLine = blockRow << 3;
|
||
|
|
for (var i = 0; i < 8; i++)
|
||
|
|
lines.push(new Uint8Array(samplesPerLine));
|
||
|
|
for (var blockCol = 0; blockCol < blocksPerLine; blockCol++) {
|
||
|
|
quantizeAndInverse(component.blocks[blockRow][blockCol], r, R);
|
||
|
|
var offset = 0;
|
||
|
|
var sample = blockCol << 3;
|
||
|
|
for (var j = 0; j < 8; j++) {
|
||
|
|
var line = lines[scanLine + j];
|
||
|
|
for (var i = 0; i < 8; i++)
|
||
|
|
line[sample + i] = r[offset++];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return lines;
|
||
|
|
}
|
||
|
|
function clampTo8bit(a) {
|
||
|
|
return a < 0 ? 0 : a > 255 ? 255 : a;
|
||
|
|
}
|
||
|
|
function parse(data) {
|
||
|
|
var self = {
|
||
|
|
width: 0,
|
||
|
|
height: 0,
|
||
|
|
comments: [],
|
||
|
|
adobe: undefined,
|
||
|
|
components: [],
|
||
|
|
exifBuffer: undefined,
|
||
|
|
jfif: undefined,
|
||
|
|
};
|
||
|
|
var maxResolutionInPixels = maxResolutionInMP * 1000 * 1000;
|
||
|
|
var offset = 0;
|
||
|
|
function readUint16() {
|
||
|
|
var value = (data[offset] << 8) | data[offset + 1];
|
||
|
|
offset += 2;
|
||
|
|
return value;
|
||
|
|
}
|
||
|
|
function readDataBlock() {
|
||
|
|
var length = readUint16();
|
||
|
|
var array = data.subarray(offset, offset + length - 2);
|
||
|
|
offset += array.length;
|
||
|
|
return array;
|
||
|
|
}
|
||
|
|
function prepareComponents(frame) {
|
||
|
|
var maxH = 0, maxV = 0;
|
||
|
|
for (var componentId in frame.components) {
|
||
|
|
if (frame.components.hasOwnProperty(componentId)) {
|
||
|
|
var component = frame.components[componentId];
|
||
|
|
if (maxH < component.h)
|
||
|
|
maxH = component.h;
|
||
|
|
if (maxV < component.v)
|
||
|
|
maxV = component.v;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
var mcusPerLine = Math.ceil(frame.samplesPerLine / 8 / maxH);
|
||
|
|
var mcusPerColumn = Math.ceil(frame.scanLines / 8 / maxV);
|
||
|
|
for (var componentId in frame.components) {
|
||
|
|
if (frame.components.hasOwnProperty(componentId)) {
|
||
|
|
var component = frame.components[componentId];
|
||
|
|
var blocksPerLine = Math.ceil(Math.ceil(frame.samplesPerLine / 8) * component.h / maxH);
|
||
|
|
var blocksPerColumn = Math.ceil(Math.ceil(frame.scanLines / 8) * component.v / maxV);
|
||
|
|
var blocksPerLineForMcu = mcusPerLine * component.h;
|
||
|
|
var blocksPerColumnForMcu = mcusPerColumn * component.v;
|
||
|
|
var blocksToAllocate = blocksPerColumnForMcu * blocksPerLineForMcu;
|
||
|
|
var blocks = [];
|
||
|
|
// Each block is a Int32Array of length 64 (4 x 64 = 256 bytes)
|
||
|
|
requestMemoryAllocation(blocksToAllocate * 256);
|
||
|
|
for (var i = 0; i < blocksPerColumnForMcu; i++) {
|
||
|
|
var row = [];
|
||
|
|
for (var j = 0; j < blocksPerLineForMcu; j++) {
|
||
|
|
row.push(new Int32Array(64));
|
||
|
|
}
|
||
|
|
blocks.push(row);
|
||
|
|
}
|
||
|
|
component.blocksPerLine = blocksPerLine;
|
||
|
|
component.blocksPerColumn = blocksPerColumn;
|
||
|
|
component.blocks = blocks;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
frame.maxH = maxH;
|
||
|
|
frame.maxV = maxV;
|
||
|
|
frame.mcusPerLine = mcusPerLine;
|
||
|
|
frame.mcusPerColumn = mcusPerColumn;
|
||
|
|
}
|
||
|
|
var jfif = null;
|
||
|
|
var adobe = null;
|
||
|
|
var frame = undefined;
|
||
|
|
var resetInterval = 0;
|
||
|
|
var quantizationTables = [];
|
||
|
|
var frames = [];
|
||
|
|
var huffmanTablesAC = [];
|
||
|
|
var huffmanTablesDC = [];
|
||
|
|
var fileMarker = readUint16();
|
||
|
|
var malformedDataOffset = -1;
|
||
|
|
if (fileMarker != 0xFFD8) { // SOI (Start of Image)
|
||
|
|
throw new Error('SOI not found');
|
||
|
|
}
|
||
|
|
fileMarker = readUint16();
|
||
|
|
while (fileMarker != 0xFFD9) { // EOI (End of image)
|
||
|
|
switch (fileMarker) {
|
||
|
|
case 0xFF00: break;
|
||
|
|
case 0xFFE0: // APP0 (Application Specific)
|
||
|
|
case 0xFFE1: // APP1
|
||
|
|
case 0xFFE2: // APP2
|
||
|
|
case 0xFFE3: // APP3
|
||
|
|
case 0xFFE4: // APP4
|
||
|
|
case 0xFFE5: // APP5
|
||
|
|
case 0xFFE6: // APP6
|
||
|
|
case 0xFFE7: // APP7
|
||
|
|
case 0xFFE8: // APP8
|
||
|
|
case 0xFFE9: // APP9
|
||
|
|
case 0xFFEA: // APP10
|
||
|
|
case 0xFFEB: // APP11
|
||
|
|
case 0xFFEC: // APP12
|
||
|
|
case 0xFFED: // APP13
|
||
|
|
case 0xFFEE: // APP14
|
||
|
|
case 0xFFEF: // APP15
|
||
|
|
case 0xFFFE: { // COM (Comment)
|
||
|
|
var appData = readDataBlock();
|
||
|
|
if (fileMarker === 0xFFFE) {
|
||
|
|
var comment = '';
|
||
|
|
for (var ii = 0; ii < appData.byteLength; ii++) {
|
||
|
|
comment += String.fromCharCode(appData[ii]);
|
||
|
|
}
|
||
|
|
self.comments.push(comment);
|
||
|
|
}
|
||
|
|
if (fileMarker === 0xFFE0) {
|
||
|
|
if (appData[0] === 0x4A && appData[1] === 0x46 && appData[2] === 0x49 &&
|
||
|
|
appData[3] === 0x46 && appData[4] === 0) { // 'JFIF\x00'
|
||
|
|
jfif = {
|
||
|
|
version: { major: appData[5], minor: appData[6] },
|
||
|
|
densityUnits: appData[7],
|
||
|
|
xDensity: (appData[8] << 8) | appData[9],
|
||
|
|
yDensity: (appData[10] << 8) | appData[11],
|
||
|
|
thumbWidth: appData[12],
|
||
|
|
thumbHeight: appData[13],
|
||
|
|
thumbData: appData.subarray(14, 14 + 3 * appData[12] * appData[13])
|
||
|
|
};
|
||
|
|
}
|
||
|
|
}
|
||
|
|
// TODO APP1 - Exif
|
||
|
|
if (fileMarker === 0xFFE1) {
|
||
|
|
if (appData[0] === 0x45 &&
|
||
|
|
appData[1] === 0x78 &&
|
||
|
|
appData[2] === 0x69 &&
|
||
|
|
appData[3] === 0x66 &&
|
||
|
|
appData[4] === 0) { // 'EXIF\x00'
|
||
|
|
self.exifBuffer = appData.subarray(5, appData.length);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if (fileMarker === 0xFFEE) {
|
||
|
|
if (appData[0] === 0x41 && appData[1] === 0x64 && appData[2] === 0x6F &&
|
||
|
|
appData[3] === 0x62 && appData[4] === 0x65 && appData[5] === 0) { // 'Adobe\x00'
|
||
|
|
adobe = {
|
||
|
|
version: appData[6],
|
||
|
|
flags0: (appData[7] << 8) | appData[8],
|
||
|
|
flags1: (appData[9] << 8) | appData[10],
|
||
|
|
transformCode: appData[11]
|
||
|
|
};
|
||
|
|
}
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
case 0xFFDB: { // DQT (Define Quantization Tables)
|
||
|
|
var quantizationTablesLength = readUint16();
|
||
|
|
var quantizationTablesEnd = quantizationTablesLength + offset - 2;
|
||
|
|
while (offset < quantizationTablesEnd) {
|
||
|
|
var quantizationTableSpec = data[offset++];
|
||
|
|
requestMemoryAllocation(64 * 4);
|
||
|
|
var tableData = new Int32Array(64);
|
||
|
|
if ((quantizationTableSpec >> 4) === 0) { // 8 bit values
|
||
|
|
for (var j = 0; j < 64; j++) {
|
||
|
|
var z = dctZigZag[j];
|
||
|
|
tableData[z] = data[offset++];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else if ((quantizationTableSpec >> 4) === 1) { //16 bit
|
||
|
|
for (var j = 0; j < 64; j++) {
|
||
|
|
var z = dctZigZag[j];
|
||
|
|
tableData[z] = readUint16();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else
|
||
|
|
throw new Error('DQT: invalid table spec');
|
||
|
|
quantizationTables[quantizationTableSpec & 15] = tableData;
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
case 0xFFC0: // SOF0 (Start of Frame, Baseline DCT)
|
||
|
|
case 0xFFC1: // SOF1 (Start of Frame, Extended DCT)
|
||
|
|
case 0xFFC2: { // SOF2 (Start of Frame, Progressive DCT)
|
||
|
|
readUint16(); // skip data length
|
||
|
|
frame = {
|
||
|
|
extended: (fileMarker === 0xFFC1),
|
||
|
|
progressive: (fileMarker === 0xFFC2),
|
||
|
|
precision: data[offset++],
|
||
|
|
scanLines: readUint16(),
|
||
|
|
samplesPerLine: readUint16(),
|
||
|
|
components: {},
|
||
|
|
componentsOrder: [],
|
||
|
|
maxH: 0,
|
||
|
|
maxV: 0,
|
||
|
|
mcusPerLine: 0,
|
||
|
|
mcusPerColumn: 0,
|
||
|
|
};
|
||
|
|
var pixelsInFrame = frame.scanLines * frame.samplesPerLine;
|
||
|
|
if (pixelsInFrame > maxResolutionInPixels) {
|
||
|
|
var exceededAmount = Math.ceil((pixelsInFrame - maxResolutionInPixels) / 1e6);
|
||
|
|
throw new Error("maxResolutionInMP limit exceeded by ".concat(exceededAmount, "MP"));
|
||
|
|
}
|
||
|
|
var componentsCount = data[offset++];
|
||
|
|
for (var i = 0; i < componentsCount; i++) {
|
||
|
|
var componentId = data[offset];
|
||
|
|
var h = data[offset + 1] >> 4;
|
||
|
|
var v = data[offset + 1] & 15;
|
||
|
|
var qId = data[offset + 2];
|
||
|
|
frame.componentsOrder.push(componentId);
|
||
|
|
frame.components[componentId] = {
|
||
|
|
h: h,
|
||
|
|
v: v,
|
||
|
|
quantizationIdx: qId,
|
||
|
|
blocksPerColumn: 0,
|
||
|
|
blocksPerLine: 0,
|
||
|
|
blocks: [],
|
||
|
|
pred: 0,
|
||
|
|
};
|
||
|
|
offset += 3;
|
||
|
|
}
|
||
|
|
prepareComponents(frame);
|
||
|
|
frames.push(frame);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
case 0xFFC4: { // DHT (Define Huffman Tables)
|
||
|
|
var huffmanLength = readUint16();
|
||
|
|
for (var i = 2; i < huffmanLength;) {
|
||
|
|
var huffmanTableSpec = data[offset++];
|
||
|
|
var codeLengths = new Uint8Array(16);
|
||
|
|
var codeLengthSum = 0;
|
||
|
|
for (var j = 0; j < 16; j++, offset++) {
|
||
|
|
codeLengthSum += (codeLengths[j] = data[offset]);
|
||
|
|
}
|
||
|
|
requestMemoryAllocation(16 + codeLengthSum);
|
||
|
|
var huffmanValues = new Uint8Array(codeLengthSum);
|
||
|
|
for (var j = 0; j < codeLengthSum; j++, offset++) {
|
||
|
|
huffmanValues[j] = data[offset];
|
||
|
|
}
|
||
|
|
i += 17 + codeLengthSum;
|
||
|
|
var index = huffmanTableSpec & 15;
|
||
|
|
var table = (huffmanTableSpec >> 4) === 0 ? huffmanTablesDC : huffmanTablesAC;
|
||
|
|
table[index] = buildHuffmanTable(codeLengths, huffmanValues);
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
case 0xFFDD: // DRI (Define Restart Interval)
|
||
|
|
readUint16(); // skip data length
|
||
|
|
resetInterval = readUint16();
|
||
|
|
break;
|
||
|
|
case 0xFFDC: // Number of Lines marker
|
||
|
|
readUint16(); // skip data length
|
||
|
|
readUint16(); // Ignore this data since it represents the image height
|
||
|
|
break;
|
||
|
|
case 0xFFDA: { // SOS (Start of Scan)
|
||
|
|
readUint16(); // skip data length
|
||
|
|
var selectorsCount = data[offset++];
|
||
|
|
var components = [];
|
||
|
|
for (var i = 0; i < selectorsCount; i++) {
|
||
|
|
var component = frame.components[data[offset++]];
|
||
|
|
var tableSpec = data[offset++];
|
||
|
|
component.huffmanTableDC = huffmanTablesDC[tableSpec >> 4];
|
||
|
|
component.huffmanTableAC = huffmanTablesAC[tableSpec & 15];
|
||
|
|
components.push(component);
|
||
|
|
}
|
||
|
|
var spectralStart = data[offset++];
|
||
|
|
var spectralEnd = data[offset++];
|
||
|
|
var successiveApproximation = data[offset++];
|
||
|
|
var processed = decodeScan(data, offset, frame, components, resetInterval, spectralStart, spectralEnd, successiveApproximation >> 4, successiveApproximation & 15);
|
||
|
|
offset += processed;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
case 0xFFFF: // Fill bytes
|
||
|
|
if (data[offset] !== 0xFF) { // Avoid skipping a valid marker.
|
||
|
|
offset--;
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
default: {
|
||
|
|
if (data[offset - 3] == 0xFF && data[offset - 2] >= 0xC0 && data[offset - 2] <= 0xFE) {
|
||
|
|
// could be incorrect encoding -- last 0xFF byte of the previous
|
||
|
|
// block was eaten by the encoder
|
||
|
|
offset -= 3;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
else if (fileMarker === 0xE0 || fileMarker == 0xE1) {
|
||
|
|
// Recover from malformed APP1 markers popular in some phone models.
|
||
|
|
// See https://github.com/eugeneware/jpeg-js/issues/82
|
||
|
|
if (malformedDataOffset !== -1) {
|
||
|
|
throw new Error("first unknown JPEG marker at offset ".concat(malformedDataOffset.toString(16), ", second unknown JPEG marker ").concat(fileMarker.toString(16), " at offset ").concat((offset - 1).toString(16)));
|
||
|
|
}
|
||
|
|
malformedDataOffset = offset - 1;
|
||
|
|
var nextOffset = readUint16();
|
||
|
|
if (data[offset + nextOffset - 2] === 0xFF) {
|
||
|
|
offset += nextOffset - 2;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
throw new Error('unknown JPEG marker ' + fileMarker.toString(16));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
fileMarker = readUint16();
|
||
|
|
}
|
||
|
|
if (frames.length != 1)
|
||
|
|
throw new Error('only single frame JPEGs supported');
|
||
|
|
// set each frame's components quantization table
|
||
|
|
for (var i = 0; i < frames.length; i++) {
|
||
|
|
var cp = frames[i].components;
|
||
|
|
for (var j in cp) { // TODO: don't use `in`
|
||
|
|
cp[j].quantizationTable = quantizationTables[cp[j].quantizationIdx];
|
||
|
|
delete cp[j].quantizationIdx; // TODO: why ???
|
||
|
|
}
|
||
|
|
}
|
||
|
|
self.width = frame.samplesPerLine;
|
||
|
|
self.height = frame.scanLines;
|
||
|
|
self.jfif = jfif;
|
||
|
|
self.adobe = adobe;
|
||
|
|
self.components = [];
|
||
|
|
for (var i = 0; i < frame.componentsOrder.length; i++) {
|
||
|
|
var component = frame.components[frame.componentsOrder[i]];
|
||
|
|
self.components.push({
|
||
|
|
lines: buildComponentData(component),
|
||
|
|
scaleX: component.h / frame.maxH,
|
||
|
|
scaleY: component.v / frame.maxV
|
||
|
|
});
|
||
|
|
}
|
||
|
|
return self;
|
||
|
|
}
|
||
|
|
function getData(decoded) {
|
||
|
|
var offset = 0;
|
||
|
|
var colorTransform = false;
|
||
|
|
var width = decoded.width;
|
||
|
|
var height = decoded.height;
|
||
|
|
var dataLength = width * height * decoded.components.length;
|
||
|
|
requestMemoryAllocation(dataLength);
|
||
|
|
var data = new Uint8Array(dataLength);
|
||
|
|
switch (decoded.components.length) {
|
||
|
|
case 1: {
|
||
|
|
var component1 = decoded.components[0];
|
||
|
|
for (var y = 0; y < height; y++) {
|
||
|
|
var component1Line = component1.lines[0 | (y * component1.scaleY)];
|
||
|
|
for (var x = 0; x < width; x++) {
|
||
|
|
var Y = component1Line[0 | (x * component1.scaleX)];
|
||
|
|
data[offset++] = Y;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
case 2: {
|
||
|
|
// PDF might compress two component data in custom colorspace
|
||
|
|
var component1 = decoded.components[0];
|
||
|
|
var component2 = decoded.components[1];
|
||
|
|
for (var y = 0; y < height; y++) {
|
||
|
|
var component1Line = component1.lines[0 | (y * component1.scaleY)];
|
||
|
|
var component2Line = component2.lines[0 | (y * component2.scaleY)];
|
||
|
|
for (var x = 0; x < width; x++) {
|
||
|
|
var Y1 = component1Line[0 | (x * component1.scaleX)];
|
||
|
|
data[offset++] = Y1;
|
||
|
|
var Y2 = component2Line[0 | (x * component2.scaleX)];
|
||
|
|
data[offset++] = Y2;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
case 3: {
|
||
|
|
// The default transform for three components is true
|
||
|
|
colorTransform = true;
|
||
|
|
// The adobe transform marker overrides any previous setting
|
||
|
|
if (decoded.adobe && decoded.adobe.transformCode)
|
||
|
|
colorTransform = true;
|
||
|
|
var component1 = decoded.components[0];
|
||
|
|
var component2 = decoded.components[1];
|
||
|
|
var component3 = decoded.components[2];
|
||
|
|
for (var y = 0; y < height; y++) {
|
||
|
|
var component1Line = component1.lines[0 | (y * component1.scaleY)];
|
||
|
|
var component2Line = component2.lines[0 | (y * component2.scaleY)];
|
||
|
|
var component3Line = component3.lines[0 | (y * component3.scaleY)];
|
||
|
|
for (var x = 0; x < width; x++) {
|
||
|
|
var Y = void 0, Cb = void 0, Cr = void 0, R = void 0, G = void 0, B = void 0;
|
||
|
|
if (!colorTransform) {
|
||
|
|
R = component1Line[0 | (x * component1.scaleX)];
|
||
|
|
G = component2Line[0 | (x * component2.scaleX)];
|
||
|
|
B = component3Line[0 | (x * component3.scaleX)];
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
Y = component1Line[0 | (x * component1.scaleX)];
|
||
|
|
Cb = component2Line[0 | (x * component2.scaleX)];
|
||
|
|
Cr = component3Line[0 | (x * component3.scaleX)];
|
||
|
|
R = clampTo8bit(Y + 1.402 * (Cr - 128));
|
||
|
|
G = clampTo8bit(Y - 0.3441363 * (Cb - 128) - 0.71413636 * (Cr - 128));
|
||
|
|
B = clampTo8bit(Y + 1.772 * (Cb - 128));
|
||
|
|
}
|
||
|
|
data[offset++] = R;
|
||
|
|
data[offset++] = G;
|
||
|
|
data[offset++] = B;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
case 4: {
|
||
|
|
if (!decoded.adobe)
|
||
|
|
throw new Error('Unsupported color mode (4 components)');
|
||
|
|
// The default transform for four components is false
|
||
|
|
colorTransform = false;
|
||
|
|
// The adobe transform marker overrides any previous setting
|
||
|
|
if (decoded.adobe && decoded.adobe.transformCode)
|
||
|
|
colorTransform = true;
|
||
|
|
var component1 = decoded.components[0];
|
||
|
|
var component2 = decoded.components[1];
|
||
|
|
var component3 = decoded.components[2];
|
||
|
|
var component4 = decoded.components[3];
|
||
|
|
for (var y = 0; y < height; y++) {
|
||
|
|
var component1Line = component1.lines[0 | (y * component1.scaleY)];
|
||
|
|
var component2Line = component2.lines[0 | (y * component2.scaleY)];
|
||
|
|
var component3Line = component3.lines[0 | (y * component3.scaleY)];
|
||
|
|
var component4Line = component4.lines[0 | (y * component4.scaleY)];
|
||
|
|
for (var x = 0; x < width; x++) {
|
||
|
|
var Y = void 0, Cb = void 0, Cr = void 0, K = void 0, C = void 0, M = void 0, Ye = void 0;
|
||
|
|
if (!colorTransform) {
|
||
|
|
C = component1Line[0 | (x * component1.scaleX)];
|
||
|
|
M = component2Line[0 | (x * component2.scaleX)];
|
||
|
|
Ye = component3Line[0 | (x * component3.scaleX)];
|
||
|
|
K = component4Line[0 | (x * component4.scaleX)];
|
||
|
|
}
|
||
|
|
else {
|
||
|
|
Y = component1Line[0 | (x * component1.scaleX)];
|
||
|
|
Cb = component2Line[0 | (x * component2.scaleX)];
|
||
|
|
Cr = component3Line[0 | (x * component3.scaleX)];
|
||
|
|
K = component4Line[0 | (x * component4.scaleX)];
|
||
|
|
C = 255 - clampTo8bit(Y + 1.402 * (Cr - 128));
|
||
|
|
M = 255 - clampTo8bit(Y - 0.3441363 * (Cb - 128) - 0.71413636 * (Cr - 128));
|
||
|
|
Ye = 255 - clampTo8bit(Y + 1.772 * (Cb - 128));
|
||
|
|
}
|
||
|
|
data[offset++] = 255 - C;
|
||
|
|
data[offset++] = 255 - M;
|
||
|
|
data[offset++] = 255 - Ye;
|
||
|
|
data[offset++] = 255 - K;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
default:
|
||
|
|
throw new Error('Unsupported color mode');
|
||
|
|
}
|
||
|
|
return data;
|
||
|
|
}
|
||
|
|
function decodeJpeg(encoded, createImageData) {
|
||
|
|
totalBytesAllocated = 0;
|
||
|
|
if (encoded.length === 0)
|
||
|
|
throw new Error('Empty jpeg buffer');
|
||
|
|
var decoded = parse(encoded);
|
||
|
|
requestMemoryAllocation(decoded.width * decoded.height * 4);
|
||
|
|
var data = getData(decoded);
|
||
|
|
var imageData = createImageData(decoded.width, decoded.height);
|
||
|
|
var width = imageData.width;
|
||
|
|
var height = imageData.height;
|
||
|
|
var imageDataArray = imageData.data;
|
||
|
|
var i = 0;
|
||
|
|
var j = 0;
|
||
|
|
switch (decoded.components.length) {
|
||
|
|
case 1:
|
||
|
|
for (var y = 0; y < height; y++) {
|
||
|
|
for (var x = 0; x < width; x++) {
|
||
|
|
var Y = data[i++];
|
||
|
|
imageDataArray[j++] = Y;
|
||
|
|
imageDataArray[j++] = Y;
|
||
|
|
imageDataArray[j++] = Y;
|
||
|
|
imageDataArray[j++] = 255;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
case 3:
|
||
|
|
for (var y = 0; y < height; y++) {
|
||
|
|
for (var x = 0; x < width; x++) {
|
||
|
|
var R = data[i++];
|
||
|
|
var G = data[i++];
|
||
|
|
var B = data[i++];
|
||
|
|
imageDataArray[j++] = R;
|
||
|
|
imageDataArray[j++] = G;
|
||
|
|
imageDataArray[j++] = B;
|
||
|
|
imageDataArray[j++] = 255;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
case 4:
|
||
|
|
for (var y = 0; y < height; y++) {
|
||
|
|
for (var x = 0; x < width; x++) {
|
||
|
|
var C = data[i++];
|
||
|
|
var M = data[i++];
|
||
|
|
var Y = data[i++];
|
||
|
|
var K = data[i++];
|
||
|
|
var R = 255 - clampTo8bit(C * (1 - K / 255) + K);
|
||
|
|
var G = 255 - clampTo8bit(M * (1 - K / 255) + K);
|
||
|
|
var B = 255 - clampTo8bit(Y * (1 - K / 255) + K);
|
||
|
|
imageDataArray[j++] = R;
|
||
|
|
imageDataArray[j++] = G;
|
||
|
|
imageDataArray[j++] = B;
|
||
|
|
imageDataArray[j++] = 255;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
default:
|
||
|
|
throw new Error('Unsupported color mode');
|
||
|
|
}
|
||
|
|
return imageData;
|
||
|
|
}
|
||
|
|
exports.decodeJpeg = decodeJpeg;
|
||
|
|
|
||
|
|
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