/* Copyright 2017 Mozilla Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
'use strict';
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.JpegImage = undefined;
var _typeof = typeof Symbol === "function" && typeof Symbol.iterator === "symbol" ? function (obj) { return typeof obj; } : function (obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; };
var _util = require('../shared/util');
var JpegError = function JpegErrorClosure() {
function JpegError(msg) {
this.message = 'JPEG error: ' + msg;
}
JpegError.prototype = new Error();
JpegError.prototype.name = 'JpegError';
JpegError.constructor = JpegError;
return JpegError;
}();
var JpegImage = function JpegImageClosure() {
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]);
var dctCos1 = 4017;
var dctSin1 = 799;
var dctCos3 = 3406;
var dctSin3 = 2276;
var dctCos6 = 1567;
var dctSin6 = 3784;
var dctSqrt2 = 5793;
var dctSqrt1d2 = 2896;
function JpegImage() {
this.decodeTransform = null;
this.colorTransform = -1;
}
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) {
code.push(q = {
children: [],
index: 0
});
p.children[p.index] = q.children;
p = q;
}
}
return code[0].children;
}
function getBlockBufferOffset(component, row, col) {
return 64 * ((component.blocksPerLine + 1) * row + col);
}
function decodeScan(data, offset, frame, components, resetInterval, spectralStart, spectralEnd, successivePrev, successive) {
var mcusPerLine = frame.mcusPerLine;
var progressive = frame.progressive;
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 new JpegError('unexpected marker ' + (bitsData << 8 | nextByte).toString(16));
}
}
bitsCount = 7;
return bitsData >>> 7;
}
function decodeHuffman(tree) {
var node = tree;
while (true) {
node = node[readBit()];
if (typeof node === 'number') {
return node;
}
if ((typeof node === 'undefined' ? 'undefined' : _typeof(node)) !== 'object') {
throw new JpegError('invalid huffman sequence');
}
}
}
function receive(length) {
var n = 0;
while (length > 0) {
n = n << 1 | readBit();
length--;
}
return n;
}
function receiveAndExtend(length) {
if (length === 1) {
return readBit() === 1 ? 1 : -1;
}
var n = receive(length);
if (n >= 1 << length - 1) {
return n;
}
return n + (-1 << length) + 1;
}
function decodeBaseline(component, offset) {
var t = decodeHuffman(component.huffmanTableDC);
var diff = t === 0 ? 0 : receiveAndExtend(t);
component.blockData[offset] = 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;
var z = dctZigZag[k];
component.blockData[offset + z] = receiveAndExtend(s);
k++;
}
}
function decodeDCFirst(component, offset) {
var t = decodeHuffman(component.huffmanTableDC);
var diff = t === 0 ? 0 : receiveAndExtend(t) << successive;
component.blockData[offset] = component.pred += diff;
}
function decodeDCSuccessive(component, offset) {
component.blockData[offset] |= readBit() << successive;
}
var eobrun = 0;
function decodeACFirst(component, offset) {
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;
var z = dctZigZag[k];
component.blockData[offset + z] = receiveAndExtend(s) * (1 << successive);
k++;
}
}
var successiveACState = 0,
successiveACNextValue;
function decodeACSuccessive(component, offset) {
var k = spectralStart;
var e = spectralEnd;
var r = 0;
var s;
var rs;
while (k <= e) {
var z = dctZigZag[k];
switch (successiveACState) {
case 0:
rs = decodeHuffman(component.huffmanTableAC);
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 new JpegError('invalid ACn encoding');
}
successiveACNextValue = receiveAndExtend(s);
successiveACState = r ? 2 : 3;
}
continue;
case 1:
case 2:
if (component.blockData[offset + z]) {
component.blockData[offset + z] += readBit() << successive;
} else {
r--;
if (r === 0) {
successiveACState = successiveACState === 2 ? 3 : 0;
}
}
break;
case 3:
if (component.blockData[offset + z]) {
component.blockData[offset + z] += readBit() << successive;
} else {
component.blockData[offset + z] = successiveACNextValue << successive;
successiveACState = 0;
}
break;
case 4:
if (component.blockData[offset + z]) {
component.blockData[offset + z] += 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;
var offset = getBlockBufferOffset(component, blockRow, blockCol);
decode(component, offset);
}
function decodeBlock(component, decode, mcu) {
var blockRow = mcu / component.blocksPerLine | 0;
var blockCol = mcu % component.blocksPerLine;
var offset = getBlockBufferOffset(component, blockRow, blockCol);
decode(component, offset);
}
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,
fileMarker;
var mcuExpected;
if (componentsLength === 1) {
mcuExpected = components[0].blocksPerLine * components[0].blocksPerColumn;
} else {
mcuExpected = mcusPerLine * frame.mcusPerColumn;
}
var h, v;
while (mcu < mcuExpected) {
var mcuToRead = resetInterval ? Math.min(mcuExpected - mcu, resetInterval) : mcuExpected;
for (i = 0; i < componentsLength; i++) {
components[i].pred = 0;
}
eobrun = 0;
if (componentsLength === 1) {
component = components[0];
for (n = 0; n < mcuToRead; n++) {
decodeBlock(component, decodeFn, mcu);
mcu++;
}
} else {
for (n = 0; n < mcuToRead; 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++;
}
}
bitsCount = 0;
fileMarker = findNextFileMarker(data, offset);
if (fileMarker && fileMarker.invalid) {
(0, _util.warn)('decodeScan - unexpected MCU data, next marker is: ' + fileMarker.invalid);
offset = fileMarker.offset;
}
var marker = fileMarker && fileMarker.marker;
if (!marker || marker <= 0xFF00) {
throw new JpegError('marker was not found');
}
if (marker >= 0xFFD0 && marker <= 0xFFD7) {
offset += 2;
} else {
break;
}
}
fileMarker = findNextFileMarker(data, offset);
if (fileMarker && fileMarker.invalid) {
(0, _util.warn)('decodeScan - unexpected Scan data, next marker is: ' + fileMarker.invalid);
offset = fileMarker.offset;
}
return offset - startOffset;
}
function quantizeAndInverse(component, blockBufferOffset, p) {
var qt = component.quantizationTable,
blockData = component.blockData;
var v0, v1, v2, v3, v4, v5, v6, v7;
var p0, p1, p2, p3, p4, p5, p6, p7;
var t;
if (!qt) {
throw new JpegError('missing required Quantization Table.');
}
for (var row = 0; row < 64; row += 8) {
p0 = blockData[blockBufferOffset + row];
p1 = blockData[blockBufferOffset + row + 1];
p2 = blockData[blockBufferOffset + row + 2];
p3 = blockData[blockBufferOffset + row + 3];
p4 = blockData[blockBufferOffset + row + 4];
p5 = blockData[blockBufferOffset + row + 5];
p6 = blockData[blockBufferOffset + row + 6];
p7 = blockData[blockBufferOffset + row + 7];
p0 *= qt[row];
if ((p1 | p2 | p3 | p4 | p5 | p6 | p7) === 0) {
t = dctSqrt2 * p0 + 512 >> 10;
p[row] = t;
p[row + 1] = t;
p[row + 2] = t;
p[row + 3] = t;
p[row + 4] = t;
p[row + 5] = t;
p[row + 6] = t;
p[row + 7] = t;
continue;
}
p1 *= qt[row + 1];
p2 *= qt[row + 2];
p3 *= qt[row + 3];
p4 *= qt[row + 4];
p5 *= qt[row + 5];
p6 *= qt[row + 6];
p7 *= qt[row + 7];
v0 = dctSqrt2 * p0 + 128 >> 8;
v1 = dctSqrt2 * p4 + 128 >> 8;
v2 = p2;
v3 = p6;
v4 = dctSqrt1d2 * (p1 - p7) + 128 >> 8;
v7 = dctSqrt1d2 * (p1 + p7) + 128 >> 8;
v5 = p3 << 4;
v6 = p5 << 4;
v0 = v0 + v1 + 1 >> 1;
v1 = v0 - v1;
t = v2 * dctSin6 + v3 * dctCos6 + 128 >> 8;
v2 = v2 * dctCos6 - v3 * dctSin6 + 128 >> 8;
v3 = t;
v4 = v4 + v6 + 1 >> 1;
v6 = v4 - v6;
v7 = v7 + v5 + 1 >> 1;
v5 = v7 - v5;
v0 = v0 + v3 + 1 >> 1;
v3 = v0 - v3;
v1 = v1 + v2 + 1 >> 1;
v2 = v1 - v2;
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;
p[row] = v0 + v7;
p[row + 7] = v0 - v7;
p[row + 1] = v1 + v6;
p[row + 6] = v1 - v6;
p[row + 2] = v2 + v5;
p[row + 5] = v2 - v5;
p[row + 3] = v3 + v4;
p[row + 4] = v3 - v4;
}
for (var col = 0; col < 8; ++col) {
p0 = p[col];
p1 = p[col + 8];
p2 = p[col + 16];
p3 = p[col + 24];
p4 = p[col + 32];
p5 = p[col + 40];
p6 = p[col + 48];
p7 = p[col + 56];
if ((p1 | p2 | p3 | p4 | p5 | p6 | p7) === 0) {
t = dctSqrt2 * p0 + 8192 >> 14;
t = t < -2040 ? 0 : t >= 2024 ? 255 : t + 2056 >> 4;
blockData[blockBufferOffset + col] = t;
blockData[blockBufferOffset + col + 8] = t;
blockData[blockBufferOffset + col + 16] = t;
blockData[blockBufferOffset + col + 24] = t;
blockData[blockBufferOffset + col + 32] = t;
blockData[blockBufferOffset + col + 40] = t;
blockData[blockBufferOffset + col + 48] = t;
blockData[blockBufferOffset + col + 56] = t;
continue;
}
v0 = dctSqrt2 * p0 + 2048 >> 12;
v1 = dctSqrt2 * p4 + 2048 >> 12;
v2 = p2;
v3 = p6;
v4 = dctSqrt1d2 * (p1 - p7) + 2048 >> 12;
v7 = dctSqrt1d2 * (p1 + p7) + 2048 >> 12;
v5 = p3;
v6 = p5;
v0 = (v0 + v1 + 1 >> 1) + 4112;
v1 = v0 - v1;
t = v2 * dctSin6 + v3 * dctCos6 + 2048 >> 12;
v2 = v2 * dctCos6 - v3 * dctSin6 + 2048 >> 12;
v3 = t;
v4 = v4 + v6 + 1 >> 1;
v6 = v4 - v6;
v7 = v7 + v5 + 1 >> 1;
v5 = v7 - v5;
v0 = v0 + v3 + 1 >> 1;
v3 = v0 - v3;
v1 = v1 + v2 + 1 >> 1;
v2 = v1 - v2;
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;
p0 = v0 + v7;
p7 = v0 - v7;
p1 = v1 + v6;
p6 = v1 - v6;
p2 = v2 + v5;
p5 = v2 - v5;
p3 = v3 + v4;
p4 = v3 - v4;
p0 = p0 < 16 ? 0 : p0 >= 4080 ? 255 : p0 >> 4;
p1 = p1 < 16 ? 0 : p1 >= 4080 ? 255 : p1 >> 4;
p2 = p2 < 16 ? 0 : p2 >= 4080 ? 255 : p2 >> 4;
p3 = p3 < 16 ? 0 : p3 >= 4080 ? 255 : p3 >> 4;
p4 = p4 < 16 ? 0 : p4 >= 4080 ? 255 : p4 >> 4;
p5 = p5 < 16 ? 0 : p5 >= 4080 ? 255 : p5 >> 4;
p6 = p6 < 16 ? 0 : p6 >= 4080 ? 255 : p6 >> 4;
p7 = p7 < 16 ? 0 : p7 >= 4080 ? 255 : p7 >> 4;
blockData[blockBufferOffset + col] = p0;
blockData[blockBufferOffset + col + 8] = p1;
blockData[blockBufferOffset + col + 16] = p2;
blockData[blockBufferOffset + col + 24] = p3;
blockData[blockBufferOffset + col + 32] = p4;
blockData[blockBufferOffset + col + 40] = p5;
blockData[blockBufferOffset + col + 48] = p6;
blockData[blockBufferOffset + col + 56] = p7;
}
}
function buildComponentData(frame, component) {
var blocksPerLine = component.blocksPerLine;
var blocksPerColumn = component.blocksPerColumn;
var computationBuffer = new Int16Array(64);
for (var blockRow = 0; blockRow < blocksPerColumn; blockRow++) {
for (var blockCol = 0; blockCol < blocksPerLine; blockCol++) {
var offset = getBlockBufferOffset(component, blockRow, blockCol);
quantizeAndInverse(component, offset, computationBuffer);
}
}
return component.blockData;
}
function clamp0to255(a) {
return a <= 0 ? 0 : a >= 255 ? 255 : a;
}
function findNextFileMarker(data, currentPos, startPos) {
function peekUint16(pos) {
return data[pos] << 8 | data[pos + 1];
}
var maxPos = data.length - 1;
var newPos = startPos < currentPos ? startPos : currentPos;
if (currentPos >= maxPos) {
return null;
}
var currentMarker = peekUint16(currentPos);
if (currentMarker >= 0xFFC0 && currentMarker <= 0xFFFE) {
return {
invalid: null,
marker: currentMarker,
offset: currentPos
};
}
var newMarker = peekUint16(newPos);
while (!(newMarker >= 0xFFC0 && newMarker <= 0xFFFE)) {
if (++newPos >= maxPos) {
return null;
}
newMarker = peekUint16(newPos);
}
return {
invalid: currentMarker.toString(16),
marker: newMarker,
offset: newPos
};
}
JpegImage.prototype = {
parse: function parse(data) {
function readUint16() {
var value = data[offset] << 8 | data[offset + 1];
offset += 2;
return value;
}
function readDataBlock() {
var length = readUint16();
var endOffset = offset + length - 2;
var fileMarker = findNextFileMarker(data, endOffset, offset);
if (fileMarker && fileMarker.invalid) {
(0, _util.warn)('readDataBlock - incorrect length, next marker is: ' + fileMarker.invalid);
endOffset = fileMarker.offset;
}
var array = data.subarray(offset, endOffset);
offset += array.length;
return array;
}
function prepareComponents(frame) {
var mcusPerLine = Math.ceil(frame.samplesPerLine / 8 / frame.maxH);
var mcusPerColumn = Math.ceil(frame.scanLines / 8 / frame.maxV);
for (var i = 0; i < frame.components.length; i++) {
component = frame.components[i];
var blocksPerLine = Math.ceil(Math.ceil(frame.samplesPerLine / 8) * component.h / frame.maxH);
var blocksPerColumn = Math.ceil(Math.ceil(frame.scanLines / 8) * component.v / frame.maxV);
var blocksPerLineForMcu = mcusPerLine * component.h;
var blocksPerColumnForMcu = mcusPerColumn * component.v;
var blocksBufferSize = 64 * blocksPerColumnForMcu * (blocksPerLineForMcu + 1);
component.blockData = new Int16Array(blocksBufferSize);
component.blocksPerLine = blocksPerLine;
component.blocksPerColumn = blocksPerColumn;
}
frame.mcusPerLine = mcusPerLine;
frame.mcusPerColumn = mcusPerColumn;
}
var offset = 0;
var jfif = null;
var adobe = null;
var frame, resetInterval;
var quantizationTables = [];
var huffmanTablesAC = [],
huffmanTablesDC = [];
var fileMarker = readUint16();
if (fileMarker !== 0xFFD8) {
throw new JpegError('SOI not found');
}
fileMarker = readUint16();
while (fileMarker !== 0xFFD9) {
var i, j, l;
switch (fileMarker) {
case 0xFFE0:
case 0xFFE1:
case 0xFFE2:
case 0xFFE3:
case 0xFFE4:
case 0xFFE5:
case 0xFFE6:
case 0xFFE7:
case 0xFFE8:
case 0xFFE9:
case 0xFFEA:
case 0xFFEB:
case 0xFFEC:
case 0xFFED:
case 0xFFEE:
case 0xFFEF:
case 0xFFFE:
var appData = readDataBlock();
if (fileMarker === 0xFFE0) {
if (appData[0] === 0x4A && appData[1] === 0x46 && appData[2] === 0x49 && appData[3] === 0x46 && appData[4] === 0) {
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])
};
}
}
if (fileMarker === 0xFFEE) {
if (appData[0] === 0x41 && appData[1] === 0x64 && appData[2] === 0x6F && appData[3] === 0x62 && appData[4] === 0x65) {
adobe = {
version: appData[5] << 8 | appData[6],
flags0: appData[7] << 8 | appData[8],
flags1: appData[9] << 8 | appData[10],
transformCode: appData[11]
};
}
}
break;
case 0xFFDB:
var quantizationTablesLength = readUint16();
var quantizationTablesEnd = quantizationTablesLength + offset - 2;
var z;
while (offset < quantizationTablesEnd) {
var quantizationTableSpec = data[offset++];
var tableData = new Uint16Array(64);
if (quantizationTableSpec >> 4 === 0) {
for (j = 0; j < 64; j++) {
z = dctZigZag[j];
tableData[z] = data[offset++];
}
} else if (quantizationTableSpec >> 4 === 1) {
for (j = 0; j < 64; j++) {
z = dctZigZag[j];
tableData[z] = readUint16();
}
} else {
throw new JpegError('DQT - invalid table spec');
}
quantizationTables[quantizationTableSpec & 15] = tableData;
}
break;
case 0xFFC0:
case 0xFFC1:
case 0xFFC2:
if (frame) {
throw new JpegError('Only single frame JPEGs supported');
}
readUint16();
frame = {};
frame.extended = fileMarker === 0xFFC1;
frame.progressive = fileMarker === 0xFFC2;
frame.precision = data[offset++];
frame.scanLines = readUint16();
frame.samplesPerLine = readUint16();
frame.components = [];
frame.componentIds = {};
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;
if (maxH < h) {
maxH = h;
}
if (maxV < v) {
maxV = v;
}
var qId = data[offset + 2];
l = frame.components.push({
h: h,
v: v,
quantizationId: qId,
quantizationTable: null
});
frame.componentIds[componentId] = l - 1;
offset += 3;
}
frame.maxH = maxH;
frame.maxV = maxV;
prepareComponents(frame);
break;
case 0xFFC4:
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:
readUint16();
resetInterval = readUint16();
break;
case 0xFFDA:
readUint16();
var selectorsCount = data[offset++];
var components = [],
component;
for (i = 0; i < selectorsCount; i++) {
var componentIndex = frame.componentIds[data[offset++]];
component = frame.components[componentIndex];
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:
if (data[offset] !== 0xFF) {
offset--;
}
break;
default:
if (data[offset - 3] === 0xFF && data[offset - 2] >= 0xC0 && data[offset - 2] <= 0xFE) {
offset -= 3;
break;
}
throw new JpegError('unknown marker ' + fileMarker.toString(16));
}
fileMarker = readUint16();
}
this.width = frame.samplesPerLine;
this.height = frame.scanLines;
this.jfif = jfif;
this.adobe = adobe;
this.components = [];
for (i = 0; i < frame.components.length; i++) {
component = frame.components[i];
var quantizationTable = quantizationTables[component.quantizationId];
if (quantizationTable) {
component.quantizationTable = quantizationTable;
}
this.components.push({
output: buildComponentData(frame, component),
scaleX: component.h / frame.maxH,
scaleY: component.v / frame.maxV,
blocksPerLine: component.blocksPerLine,
blocksPerColumn: component.blocksPerColumn
});
}
this.numComponents = this.components.length;
},
_getLinearizedBlockData: function getLinearizedBlockData(width, height) {
var scaleX = this.width / width,
scaleY = this.height / height;
var component, componentScaleX, componentScaleY, blocksPerScanline;
var x, y, i, j, k;
var index;
var offset = 0;
var output;
var numComponents = this.components.length;
var dataLength = width * height * numComponents;
var data = new Uint8Array(dataLength);
var xScaleBlockOffset = new Uint32Array(width);
var mask3LSB = 0xfffffff8;
for (i = 0; i < numComponents; i++) {
component = this.components[i];
componentScaleX = component.scaleX * scaleX;
componentScaleY = component.scaleY * scaleY;
offset = i;
output = component.output;
blocksPerScanline = component.blocksPerLine + 1 << 3;
for (x = 0; x < width; x++) {
j = 0 | x * componentScaleX;
xScaleBlockOffset[x] = (j & mask3LSB) << 3 | j & 7;
}
for (y = 0; y < height; y++) {
j = 0 | y * componentScaleY;
index = blocksPerScanline * (j & mask3LSB) | (j & 7) << 3;
for (x = 0; x < width; x++) {
data[offset] = output[index + xScaleBlockOffset[x]];
offset += numComponents;
}
}
}
var transform = this.decodeTransform;
if (transform) {
for (i = 0; i < dataLength;) {
for (j = 0, k = 0; j < numComponents; j++, i++, k += 2) {
data[i] = (data[i] * transform[k] >> 8) + transform[k + 1];
}
}
}
return data;
},
_isColorConversionNeeded: function _isColorConversionNeeded() {
if (this.adobe) {
return !!this.adobe.transformCode;
}
if (this.numComponents === 3) {
if (this.colorTransform === 0) {
return false;
}
return true;
}
if (this.colorTransform === 1) {
return true;
}
return false;
},
_convertYccToRgb: function convertYccToRgb(data) {
var Y, Cb, Cr;
for (var i = 0, length = data.length; i < length; i += 3) {
Y = data[i];
Cb = data[i + 1];
Cr = data[i + 2];
data[i] = clamp0to255(Y - 179.456 + 1.402 * Cr);
data[i + 1] = clamp0to255(Y + 135.459 - 0.344 * Cb - 0.714 * Cr);
data[i + 2] = clamp0to255(Y - 226.816 + 1.772 * Cb);
}
return data;
},
_convertYcckToRgb: function convertYcckToRgb(data) {
var Y, Cb, Cr, k;
var offset = 0;
for (var i = 0, length = data.length; i < length; i += 4) {
Y = data[i];
Cb = data[i + 1];
Cr = data[i + 2];
k = data[i + 3];
var r = -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);
var g = 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);
var b = -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);
data[offset++] = clamp0to255(r);
data[offset++] = clamp0to255(g);
data[offset++] = clamp0to255(b);
}
return data;
},
_convertYcckToCmyk: function convertYcckToCmyk(data) {
var Y, Cb, Cr;
for (var i = 0, length = data.length; i < length; i += 4) {
Y = data[i];
Cb = data[i + 1];
Cr = data[i + 2];
data[i] = clamp0to255(434.456 - Y - 1.402 * Cr);
data[i + 1] = clamp0to255(119.541 - Y + 0.344 * Cb + 0.714 * Cr);
data[i + 2] = clamp0to255(481.816 - Y - 1.772 * Cb);
}
return data;
},
_convertCmykToRgb: function convertCmykToRgb(data) {
var c, m, y, k;
var offset = 0;
var min = -255 * 255 * 255;
var scale = 1 / 255 / 255;
for (var i = 0, length = data.length; i < length; i += 4) {
c = data[i];
m = data[i + 1];
y = data[i + 2];
k = data[i + 3];
var r = c * (-4.387332384609988 * c + 54.48615194189176 * m + 18.82290502165302 * y + 212.25662451639585 * k - 72734.4411664936) + m * (1.7149763477362134 * m - 5.6096736904047315 * y - 17.873870861415444 * k - 1401.7366389350734) + y * (-2.5217340131683033 * y - 21.248923337353073 * k + 4465.541406466231) - k * (21.86122147463605 * k + 48317.86113160301);
var g = c * (8.841041422036149 * c + 60.118027045597366 * m + 6.871425592049007 * y + 31.159100130055922 * k - 20220.756542821975) + m * (-15.310361306967817 * m + 17.575251261109482 * y + 131.35250912493976 * k - 48691.05921601825) + y * (4.444339102852739 * y + 9.8632861493405 * k - 6341.191035517494) - k * (20.737325471181034 * k + 47890.15695978492);
var b = c * (0.8842522430003296 * c + 8.078677503112928 * m + 30.89978309703729 * y - 0.23883238689178934 * k - 3616.812083916688) + m * (10.49593273432072 * m + 63.02378494754052 * y + 50.606957656360734 * k - 28620.90484698408) + y * (0.03296041114873217 * y + 115.60384449646641 * k - 49363.43385999684) - k * (22.33816807309886 * k + 45932.16563550634);
data[offset++] = r >= 0 ? 255 : r <= min ? 0 : 255 + r * scale | 0;
data[offset++] = g >= 0 ? 255 : g <= min ? 0 : 255 + g * scale | 0;
data[offset++] = b >= 0 ? 255 : b <= min ? 0 : 255 + b * scale | 0;
}
return data;
},
getData: function getData(width, height, forceRGBoutput) {
if (this.numComponents > 4) {
throw new JpegError('Unsupported color mode');
}
var data = this._getLinearizedBlockData(width, height);
if (this.numComponents === 1 && forceRGBoutput) {
var dataLength = data.length;
var rgbData = new Uint8Array(dataLength * 3);
var offset = 0;
for (var i = 0; i < dataLength; i++) {
var grayColor = data[i];
rgbData[offset++] = grayColor;
rgbData[offset++] = grayColor;
rgbData[offset++] = grayColor;
}
return rgbData;
} else if (this.numComponents === 3 && this._isColorConversionNeeded()) {
return this._convertYccToRgb(data);
} else if (this.numComponents === 4) {
if (this._isColorConversionNeeded()) {
if (forceRGBoutput) {
return this._convertYcckToRgb(data);
}
return this._convertYcckToCmyk(data);
} else if (forceRGBoutput) {
return this._convertCmykToRgb(data);
}
}
return data;
}
};
return JpegImage;
}();
exports.JpegImage = JpegImage;