--- /dev/null
+/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- /
+/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
+
+// - The JPEG specification can be found in the ITU CCITT Recommendation T.81
+// (www.w3.org/Graphics/JPEG/itu-t81.pdf)
+// - The JFIF specification can be found in the JPEG File Interchange Format
+// (www.w3.org/Graphics/JPEG/jfif3.pdf)
+// - The Adobe Application-Specific JPEG markers in the Supporting the DCT Filters
+// in PostScript Level 2, Technical Note #5116
+// (partners.adobe.com/public/developer/en/ps/sdk/5116.DCT_Filter.pdf)
+
+var JpegImage = (function jpegImage() {
+ "use strict";
+
+ function constructor(colorTransform) {
+ this.colorTransform = typeof colorTransform !== 'undefined' ? colorTransform : -1;
+ }
+
+ var iDCTTables = (function initDCTTables() {
+ var cosTables = [], i, j;
+ for (i = 0; i < 8; i++) {
+ cosTables.push(new Float32Array(8));
+ for (j = 0; j < 8; j++)
+ cosTables[i][j] = Math.cos((2 * i + 1) * j * Math.PI / 16) *
+ (j > 0 ? 1 : 1/Math.sqrt(2));
+ }
+
+ var zzTransform = new Int32Array([
+ 0, 1, 5, 6, 14, 15, 27, 28, 2, 4, 7, 13, 16, 26, 29, 42, 3, 8, 12,
+ 17, 25, 30, 41, 43, 9, 11, 18, 24, 31, 40, 44, 53, 10, 19, 23, 32,
+ 39, 45, 52, 54, 20, 22, 33, 38, 46, 51, 55, 60, 21, 34, 37, 47,
+ 50, 56, 59, 61, 35, 36, 48, 49, 57, 58, 62, 63]);
+
+ var x, y, u, v;
+ var tables = [];
+ for (y = 0; y < 8; y++) {
+ var cosTable_y = cosTables[y];
+ for (x = 0; x < 8; x++) {
+ var cosTable_x = cosTables[x];
+ var table = new Float32Array(64);
+ i = 0;
+ for (v = 0; v < 8; v++) {
+ for (u = 0; u < 8; u++)
+ table[zzTransform[i++]] = cosTable_x[u] * cosTable_y[v];
+ }
+ tables.push(table);
+ }
+ }
+ return tables;
+ })();
+
+ function buildHuffmanTable(codeLengths, values) {
+ var k = 0, code = [], i, j, length = 16;
+ while (length > 0 && !codeLengths[length - 1])
+ length--;
+ code.push({children: [], index: 0});
+ var p = code[0], q;
+ for (i = 0; i < length; i++) {
+ for (j = 0; j < codeLengths[i]; j++) {
+ p = code.pop();
+ p.children[p.index] = values[k];
+ while (p.index > 0) {
+ p = code.pop();
+ }
+ p.index++;
+ code.push(p);
+ while (code.length <= i) {
+ code.push(q = {children: [], index: 0});
+ p.children[p.index] = q.children;
+ p = q;
+ }
+ k++;
+ }
+ if (i + 1 < length) {
+ // p here points to last code
+ code.push(q = {children: [], index: 0});
+ p.children[p.index] = q.children;
+ p = q;
+ }
+ }
+ return code[0].children;
+ }
+
+ function decodeScan(data, offset,
+ frame, components, resetInterval,
+ spectralStart, spectralEnd,
+ successivePrev, successive) {
+ var precision = frame.precision;
+ var samplesPerLine = frame.samplesPerLine;
+ var scanLines = frame.scanLines;
+ var mcusPerLine = frame.mcusPerLine;
+ var progressive = frame.progressive;
+ var maxH = frame.maxH, maxV = frame.maxV;
+
+ var startOffset = offset, bitsData = 0, bitsCount = 0;
+ function readBit() {
+ if (bitsCount > 0) {
+ bitsCount--;
+ return (bitsData >> bitsCount) & 1;
+ }
+ bitsData = data[offset++];
+ if (bitsData == 0xFF) {
+ var nextByte = data[offset++];
+ if (nextByte) {
+ throw "unexpected marker: " + ((bitsData << 8) | nextByte).toString(16);
+ }
+ // unstuff 0
+ }
+ bitsCount = 7;
+ return bitsData >>> 7;
+ }
+ function decodeHuffman(tree) {
+ var node = tree, bit;
+ while ((bit = readBit()) !== null) {
+ node = node[bit];
+ if (typeof node === 'number')
+ return node;
+ if (typeof node !== 'object')
+ throw "invalid huffman sequence";
+ }
+ return null;
+ }
+ function receive(length) {
+ var n = 0;
+ while (length > 0) {
+ var bit = readBit();
+ if (bit === null) return;
+ n = (n << 1) | bit;
+ length--;
+ }
+ return n;
+ }
+ function receiveAndExtend(length) {
+ var n = receive(length);
+ if (n >= 1 << (length - 1))
+ return n;
+ return n + (-1 << length) + 1;
+ }
+ function decodeBaseline(component, zz) {
+ var t = decodeHuffman(component.huffmanTableDC);
+ var diff = t === 0 ? 0 : receiveAndExtend(t);
+ zz[0]= (component.pred += diff);
+ var k = 1;
+ while (k < 64) {
+ var rs = decodeHuffman(component.huffmanTableAC);
+ var s = rs & 15, r = rs >> 4;
+ if (s === 0) {
+ if (r < 15)
+ break;
+ k += 16;
+ continue;
+ }
+ k += r;
+ zz[k] = receiveAndExtend(s);
+ k++;
+ }
+ }
+ function decodeDCFirst(component, zz) {
+ var t = decodeHuffman(component.huffmanTableDC);
+ var diff = t === 0 ? 0 : (receiveAndExtend(t) << successive);
+ zz[0] = (component.pred += diff);
+ }
+ function decodeDCSuccessive(component, zz) {
+ zz[0] |= readBit() << successive;
+ }
+ var eobrun = 0;
+ function decodeACFirst(component, zz) {
+ if (eobrun > 0) {
+ eobrun--;
+ return;
+ }
+ var k = spectralStart, e = spectralEnd;
+ while (k <= e) {
+ var rs = decodeHuffman(component.huffmanTableAC);
+ var s = rs & 15, r = rs >> 4;
+ if (s === 0) {
+ if (r < 15) {
+ eobrun = receive(r) + (1 << r) - 1;
+ break;
+ }
+ k += 16;
+ continue;
+ }
+ k += r;
+ zz[k] = receiveAndExtend(s) * (1 << successive);
+ k++;
+ }
+ }
+ var successiveACState = 0, successiveACNextValue;
+ function decodeACSuccessive(component, zz) {
+ var k = spectralStart, e = spectralEnd, r = 0;
+ while (k <= e) {
+ switch (successiveACState) {
+ case 0: // initial state
+ var rs = decodeHuffman(component.huffmanTableAC);
+ var s = rs & 15, r = rs >> 4;
+ if (s === 0) {
+ if (r < 15) {
+ eobrun = receive(r) + (1 << r);
+ successiveACState = 4;
+ } else {
+ r = 16;
+ successiveACState = 1;
+ }
+ } else {
+ if (s !== 1)
+ throw "invalid ACn encoding";
+ successiveACNextValue = receiveAndExtend(s);
+ successiveACState = r ? 2 : 3;
+ }
+ continue;
+ case 1: // skipping r zero items
+ case 2:
+ if (zz[k])
+ zz[k] += (readBit() << successive);
+ else {
+ r--;
+ if (r === 0)
+ successiveACState = successiveACState == 2 ? 3 : 0;
+ }
+ break;
+ case 3: // set value for a zero item
+ if (zz[k])
+ zz[k] += (readBit() << successive);
+ else {
+ zz[k] = successiveACNextValue << successive;
+ successiveACState = 0;
+ }
+ break;
+ case 4: // eob
+ if (zz[k])
+ zz[k] += (readBit() << successive);
+ break;
+ }
+ k++;
+ }
+ if (successiveACState === 4) {
+ eobrun--;
+ if (eobrun === 0)
+ successiveACState = 0;
+ }
+ }
+ function decodeMcu(component, decode, mcu, row, col) {
+ var mcuRow = (mcu / mcusPerLine) | 0;
+ var mcuCol = mcu % mcusPerLine;
+ var blockRow = mcuRow * component.v + row;
+ var blockCol = mcuCol * component.h + col;
+ decode(component, component.blocks[blockRow][blockCol]);
+ }
+ function decodeBlock(component, decode, mcu) {
+ var blockRow = (mcu / component.blocksPerLine) | 0;
+ var blockCol = mcu % component.blocksPerLine;
+ decode(component, component.blocks[blockRow][blockCol]);
+ }
+
+ var componentsLength = components.length;
+ var component, i, j, k, n;
+ var decodeFn;
+ if (progressive) {
+ if (spectralStart === 0)
+ decodeFn = successivePrev === 0 ? decodeDCFirst : decodeDCSuccessive;
+ else
+ decodeFn = successivePrev === 0 ? decodeACFirst : decodeACSuccessive;
+ } else {
+ decodeFn = decodeBaseline;
+ }
+
+ var mcu = 0, marker;
+ var mcuExpected;
+ if (componentsLength == 1) {
+ mcuExpected = components[0].blocksPerLine * components[0].blocksPerColumn;
+ } else {
+ mcuExpected = mcusPerLine * frame.mcusPerColumn;
+ }
+ if (!resetInterval) resetInterval = mcuExpected;
+
+ var h, v;
+ while (mcu < mcuExpected) {
+ // reset interval stuff
+ for (i = 0; i < componentsLength; i++)
+ components[i].pred = 0;
+ eobrun = 0;
+
+ if (componentsLength == 1) {
+ component = components[0];
+ for (n = 0; n < resetInterval; n++) {
+ decodeBlock(component, decodeFn, mcu);
+ mcu++;
+ }
+ } else {
+ for (n = 0; n < resetInterval; n++) {
+ for (i = 0; i < componentsLength; i++) {
+ component = components[i];
+ h = component.h;
+ v = component.v;
+ for (j = 0; j < v; j++) {
+ for (k = 0; k < h; k++) {
+ decodeMcu(component, decodeFn, mcu, j, k);
+ }
+ }
+ }
+ mcu++;
+ }
+ }
+
+ // find marker
+ bitsCount = 0;
+ marker = (data[offset] << 8) | data[offset + 1];
+ if (marker <= 0xFF00) {
+ throw "marker was not found";
+ }
+
+ if (marker >= 0xFFD0 && marker <= 0xFFD7) { // RSTx
+ offset += 2;
+ }
+ else
+ break;
+ }
+
+ return offset - startOffset;
+ }
+
+ function buildComponentData(frame, component) {
+ var lines = [];
+ var blocksPerLine = component.blocksPerLine;
+ var blocksPerColumn = component.blocksPerColumn;
+ var samplesPerLine = blocksPerLine << 3;
+
+ function quantizeAndInverse(zz) {
+ var qt = component.quantizationTable;
+ var precisionShift = frame.precision - 8;
+
+ var R = new Int32Array(64);
+ for (i = 0; i < 64; i++)
+ R[i] = zz[i] * qt[i];
+
+ var r = new Uint8Array(64), i, j;
+ for (i = 0; i < 64; i++) {
+ var sum = 0;
+ var table = iDCTTables[i];
+ for (j = 0; j < 64; j++)
+ sum += table[j] * R[j];
+ // TODO loosing precision?
+ var sample = 128 + ((sum / 4) >> precisionShift);
+ // clamping
+ r[i] = sample < 0 ? 0 : sample > 0xFF ? 0xFF : sample;
+ }
+ return r;
+ }
+
+ var i, j;
+ for (var blockRow = 0; blockRow < blocksPerColumn; blockRow++) {
+ var scanLine = blockRow << 3;
+ for (i = 0; i < 8; i++)
+ lines.push(new Uint8Array(samplesPerLine));
+ for (var blockCol = 0; blockCol < blocksPerLine; blockCol++) {
+ var r = quantizeAndInverse(component.blocks[blockRow][blockCol]);
+
+ var offset = 0, sample = blockCol << 3;
+ for (j = 0; j < 8; j++) {
+ var line = lines[scanLine + j];
+ for (i = 0; i < 8; i++)
+ line[sample + i] = r[offset++];
+ }
+ }
+ }
+ return lines;
+ }
+
+ constructor.prototype = {
+ load: function load(path) {
+ var xhr = new XMLHttpRequest();
+ xhr.open("GET", path, true);
+ xhr.responseType = "arraybuffer";
+ xhr.onload = (function() {
+ // TODO catch parse error
+ var data = new Uint8Array(xhr.response || xhr.mozResponseArrayBuffer);
+ this.parse(data);
+ if (this.onload)
+ this.onload();
+ }).bind(this);
+ xhr.send(null);
+ },
+ parse: function parse(data) {
+ var offset = 0, length = data.length;
+ 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;
+ var component, componentId;
+ for (componentId in frame.components) {
+ if (frame.components.hasOwnProperty(componentId)) {
+ 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 (componentId in frame.components) {
+ if (frame.components.hasOwnProperty(componentId)) {
+ 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 blocks = [];
+ 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 pixels = null;
+ var frame, resetInterval;
+ var quantizationTables = [], frames = [];
+ var huffmanTablesAC = [], huffmanTablesDC = [];
+ var fileMarker = readUint16();
+ if (fileMarker != 0xFFD8) { // SOI (Start of Image)
+ throw "SOI not found";
+ }
+
+ fileMarker = readUint16();
+ while (fileMarker != 0xFFD9) { // EOI (End of image)
+ var i, j, l;
+ switch(fileMarker) {
+ 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 === 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 === 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 quantizationTableCount = Math.floor((readUint16() - 2) / 65);
+ for (i = 0; i < quantizationTableCount; i++) {
+ var quantizationTableSpec = data[offset++];
+ var tableData = new Int32Array(64);
+ if ((quantizationTableSpec >> 4) === 0) { // 8 bit values
+ for (j = 0; j < 64; j++)
+ tableData[j] = data[offset++];
+ } else if ((quantizationTableSpec >> 4) === 1) { //16 bit
+ tableData[j] = readUint16();
+ } else
+ throw "DQT: invalid table spec";
+ quantizationTables[quantizationTableSpec & 15] = tableData;
+ }
+ break;
+
+ case 0xFFC0: // SOF0 (Start of Frame, Baseline DCT)
+ case 0xFFC2: // SOF2 (Start of Frame, Progressive DCT)
+ readUint16(); // skip data length
+ frame = {};
+ frame.progressive = (fileMarker === 0xFFC2);
+ frame.precision = data[offset++];
+ frame.scanLines = readUint16();
+ frame.samplesPerLine = readUint16();
+ frame.components = [];
+ var componentsCount = data[offset++], componentId;
+ var maxH = 0, maxV = 0;
+ for (i = 0; i < componentsCount; i++) {
+ componentId = data[offset];
+ var h = data[offset + 1] >> 4;
+ var v = data[offset + 1] & 15;
+ var qId = data[offset + 2];
+ frame.components[componentId] = {
+ h: h,
+ v: v,
+ quantizationTable: quantizationTables[qId]
+ };
+ offset += 3;
+ }
+ prepareComponents(frame);
+ frames.push(frame);
+ break;
+
+ case 0xFFC4: // DHT (Define Huffman Tables)
+ var huffmanLength = readUint16();
+ for (i = 2; i < huffmanLength;) {
+ var huffmanTableSpec = data[offset++];
+ var codeLengths = new Uint8Array(16);
+ var codeLengthSum = 0;
+ for (j = 0; j < 16; j++, offset++)
+ codeLengthSum += (codeLengths[j] = data[offset]);
+ var huffmanValues = new Uint8Array(codeLengthSum);
+ for (j = 0; j < codeLengthSum; j++, offset++)
+ huffmanValues[j] = data[offset];
+ i += 17 + codeLengthSum;
+
+ ((huffmanTableSpec >> 4) === 0 ?
+ huffmanTablesDC : huffmanTablesAC)[huffmanTableSpec & 15] =
+ buildHuffmanTable(codeLengths, huffmanValues);
+ }
+ break;
+
+ case 0xFFDD: // DRI (Define Restart Interval)
+ readUint16(); // skip data length
+ resetInterval = readUint16();
+ break;
+
+ case 0xFFDA: // SOS (Start of Scan)
+ var scanLength = readUint16();
+ var selectorsCount = data[offset++];
+ var components = [], component;
+ for (i = 0; i < selectorsCount; i++) {
+ 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;
+ default:
+ throw "unknown JPEG marker " + fileMarker.toString(16);
+ }
+ fileMarker = readUint16();
+ }
+ if (frames.length != 1)
+ throw "only single frame JPEGs supported";
+
+ this.width = frame.samplesPerLine;
+ this.height = frame.scanLines;
+ this.jfif = jfif;
+ this.adobe = adobe;
+ this.components = [];
+ for (var id in frame.components) {
+ if (frame.components.hasOwnProperty(id)) {
+ this.components.push({
+ lines: buildComponentData(frame, frame.components[id]),
+ scaleX: frame.components[id].h / frame.maxH,
+ scaleY: frame.components[id].v / frame.maxV
+ });
+ }
+ }
+ },
+ getData: function getData(width, height) {
+ function clampTo8bit(a) {
+ return a < 0 ? 0 : a > 255 ? 255 : a;
+ }
+ var scaleX = this.width / width, scaleY = this.height / height;
+
+ var component1, component2, component3, component4;
+ var component1Line, component2Line, component3Line, component4Line;
+ var x, y;
+ var offset = 0;
+ var Y, Cb, Cr, K, C, M, Ye, R, G, B;
+ var colorTransform;
+ var dataLength = width * height * this.components.length;
+ var data = new Uint8Array(dataLength);
+ switch (this.components.length) {
+ case 1:
+ component1 = this.components[0];
+ for (y = 0; y < height; y++) {
+ component1Line = component1.lines[0 | (y * component1.scaleY * scaleY)];
+ for (x = 0; x < width; x++) {
+ Y = component1Line[0 | (x * component1.scaleX * scaleX)];
+
+ data[offset++] = Y;
+ }
+ }
+ break;
+ case 3:
+ // The default transform for three components is true
+ colorTransform = true;
+ // The adobe transform marker overrides any previous setting
+ if (this.adobe && this.adobe.transformCode)
+ colorTransform = true;
+ else if (typeof this.colorTransform != -1)
+ colorTransform = this.colorTransform == true;
+
+ component1 = this.components[0];
+ component2 = this.components[1];
+ component3 = this.components[2];
+ for (y = 0; y < height; y++) {
+ component1Line = component1.lines[0 | (y * component1.scaleY * scaleY)];
+ component2Line = component2.lines[0 | (y * component2.scaleY * scaleY)];
+ component3Line = component3.lines[0 | (y * component3.scaleY * scaleY)];
+ for (x = 0; x < width; x++) {
+ if (!colorTransform) {
+ R = component1Line[0 | (x * component1.scaleX * scaleX)];
+ G = component2Line[0 | (x * component2.scaleX * scaleX)];
+ B = component3Line[0 | (x * component3.scaleX * scaleX)];
+ } else {
+ Y = component1Line[0 | (x * component1.scaleX * scaleX)];
+ Cb = component2Line[0 | (x * component2.scaleX * scaleX)];
+ Cr = component3Line[0 | (x * component3.scaleX * 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 (!this.adobe)
+ throw 'Unsupported color mode (4 components)';
+ // The default transform for four components is false
+ colorTransform = false;
+ // The adobe transform marker overrides any previous setting
+ if (this.adobe && this.adobe.transformCode)
+ colorTransform = true;
+ else if (typeof this.colorTransform != -1)
+ colorTransform = this.colorTransform == true;
+
+ component1 = this.components[0];
+ component2 = this.components[1];
+ component3 = this.components[2];
+ component4 = this.components[3];
+ for (y = 0; y < height; y++) {
+ component1Line = component1.lines[0 | (y * component1.scaleY * scaleY)];
+ component2Line = component2.lines[0 | (y * component2.scaleY * scaleY)];
+ component3Line = component3.lines[0 | (y * component3.scaleY * scaleY)];
+ component4Line = component4.lines[0 | (y * component4.scaleY * scaleY)];
+ for (x = 0; x < width; x++) {
+ if (!colorTransform) {
+ C = component1Line[0 | (x * component1.scaleX * scaleX)];
+ M = component2Line[0 | (x * component2.scaleX * scaleX)];
+ Ye = component3Line[0 | (x * component3.scaleX * scaleX)];
+ K = component4Line[0 | (x * component4.scaleX * scaleX)];
+ } else {
+ Y = component1Line[0 | (x * component1.scaleX * scaleX)];
+ Cb = component2Line[0 | (x * component2.scaleX * scaleX)];
+ Cr = component3Line[0 | (x * component3.scaleX * scaleX)];
+ K = component4Line[0 | (x * component4.scaleX * 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++] = C;
+ data[offset++] = M;
+ data[offset++] = Ye;
+ data[offset++] = K;
+ }
+ }
+ break;
+ default:
+ throw 'Unsupported color mode';
+ }
+ return data;
+ },
+ copyToImageData: function copyToImageData(imageData) {
+ this.getData(imageData.data, imageData.width, imageData.height);
+ }
+ };
+
+ return constructor;
+})();
\ No newline at end of file
projects / pdf.js.git / commitdiff