[Pkg-javascript-commits] [pdf.js] 96/161: jpgjs performance improvements
David Prévot
taffit at moszumanska.debian.org
Sat Apr 19 14:16:33 UTC 2014
This is an automated email from the git hooks/post-receive script.
taffit pushed a commit to branch master
in repository pdf.js.
commit 03892a85c2adfc67e81fc4a62c0d9c82483badec
Author: Thorben Bochenek <thorbenb at opera.com>
Date: Thu Mar 20 18:01:28 2014 -0500
jpgjs performance improvements
see https://github.com/notmasteryet/jpgjs/pull/22
---
external/jpgjs/jpg.js | 461 +++++++++++++++++++++++++-------------------------
1 file changed, 234 insertions(+), 227 deletions(-)
diff --git a/external/jpgjs/jpg.js b/external/jpgjs/jpg.js
index 80a7e0e..20d8f92 100644
--- a/external/jpgjs/jpg.js
+++ b/external/jpgjs/jpg.js
@@ -88,6 +88,10 @@ var JpegImage = (function jpegImage() {
return code[0].children;
}
+ function getBlockBufferOffset(component, row, col) {
+ return 64 * (component.blocksPerLine * row + col);
+ }
+
function decodeScan(data, offset,
frame, components, resetInterval,
spectralStart, spectralEnd,
@@ -143,10 +147,10 @@ var JpegImage = (function jpegImage() {
return n;
return n + (-1 << length) + 1;
}
- function decodeBaseline(component, zz) {
+ function decodeBaseline(component, offset) {
var t = decodeHuffman(component.huffmanTableDC);
var diff = t === 0 ? 0 : receiveAndExtend(t);
- zz[0]= (component.pred += diff);
+ component.blocks[offset] = (component.pred += diff);
var k = 1;
while (k < 64) {
var rs = decodeHuffman(component.huffmanTableAC);
@@ -159,20 +163,20 @@ var JpegImage = (function jpegImage() {
}
k += r;
var z = dctZigZag[k];
- zz[z] = receiveAndExtend(s);
+ component.blocks[offset + z] = receiveAndExtend(s);
k++;
}
}
- function decodeDCFirst(component, zz) {
+ function decodeDCFirst(component, offset) {
var t = decodeHuffman(component.huffmanTableDC);
var diff = t === 0 ? 0 : (receiveAndExtend(t) << successive);
- zz[0] = (component.pred += diff);
+ component.blocks[offset] = (component.pred += diff);
}
- function decodeDCSuccessive(component, zz) {
- zz[0] |= readBit() << successive;
+ function decodeDCSuccessive(component, offset) {
+ component.blocks[offset] |= readBit() << successive;
}
var eobrun = 0;
- function decodeACFirst(component, zz) {
+ function decodeACFirst(component, offset) {
if (eobrun > 0) {
eobrun--;
return;
@@ -191,12 +195,12 @@ var JpegImage = (function jpegImage() {
}
k += r;
var z = dctZigZag[k];
- zz[z] = receiveAndExtend(s) * (1 << successive);
+ component.blocks[offset + z] = receiveAndExtend(s) * (1 << successive);
k++;
}
}
var successiveACState = 0, successiveACNextValue;
- function decodeACSuccessive(component, zz) {
+ function decodeACSuccessive(component, offset) {
var k = spectralStart, e = spectralEnd, r = 0;
while (k <= e) {
var z = dctZigZag[k];
@@ -221,25 +225,26 @@ var JpegImage = (function jpegImage() {
continue;
case 1: // skipping r zero items
case 2:
- if (zz[z])
- zz[z] += (readBit() << successive);
- else {
+ if (component.blocks[offset + z]) {
+ component.blocks[offset + z] += (readBit() << successive);
+ } else {
r--;
if (r === 0)
successiveACState = successiveACState == 2 ? 3 : 0;
}
break;
case 3: // set value for a zero item
- if (zz[z])
- zz[z] += (readBit() << successive);
- else {
- zz[z] = successiveACNextValue << successive;
+ if (component.blocks[offset + z]) {
+ component.blocks[offset + z] += (readBit() << successive);
+ } else {
+ component.blocks[offset + z] = successiveACNextValue << successive;
successiveACState = 0;
}
break;
case 4: // eob
- if (zz[z])
- zz[z] += (readBit() << successive);
+ if (component.blocks[offset + z]) {
+ component.blocks[offset + z] += (readBit() << successive);
+ }
break;
}
k++;
@@ -250,17 +255,20 @@ var JpegImage = (function jpegImage() {
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]);
+
+ decode(component, getBlockBufferOffset(component, blockRow, blockCol));
}
+
function decodeBlock(component, decode, mcu) {
var blockRow = (mcu / component.blocksPerLine) | 0;
var blockCol = mcu % component.blocksPerLine;
- decode(component, component.blocks[blockRow][blockCol]);
+ decode(component, getBlockBufferOffset(component, blockRow, blockCol));
}
var componentsLength = components.length;
@@ -330,184 +338,188 @@ var JpegImage = (function jpegImage() {
return offset - startOffset;
}
- function buildComponentData(frame, component) {
- var lines = [];
- var blocksPerLine = component.blocksPerLine;
- var blocksPerColumn = component.blocksPerColumn;
- var samplesPerLine = blocksPerLine << 3;
- var R = new Int32Array(64);
-
- // A port of poppler's IDCT method which in turn is taken from:
- // Christoph Loeffler, Adriaan Ligtenberg, George S. Moschytz,
- // "Practical Fast 1-D DCT Algorithms with 11 Multiplications",
- // IEEE Intl. Conf. on Acoustics, Speech & Signal Processing, 1989,
- // 988-991.
- function quantizeAndInverse(zz, p) {
- var qt = component.quantizationTable;
- var v0, v1, v2, v3, v4, v5, v6, v7, t;
- var i;
-
- // dequant
- for (i = 0; i < 64; i++)
- p[i] = zz[i] * qt[i];
-
- // inverse DCT on rows
- for (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) {
- t = (dctSqrt2 * p[0 + row] + 512) >> 10;
- p[0 + row] = t;
- p[1 + row] = t;
- p[2 + row] = t;
- p[3 + row] = t;
- p[4 + row] = t;
- p[5 + row] = t;
- p[6 + row] = t;
- p[7 + row] = t;
- continue;
- }
-
- // stage 4
- v0 = (dctSqrt2 * p[0 + row] + 128) >> 8;
- v1 = (dctSqrt2 * p[4 + row] + 128) >> 8;
- v2 = p[2 + row];
- v3 = p[6 + row];
- v4 = (dctSqrt1d2 * (p[1 + row] - p[7 + row]) + 128) >> 8;
- v7 = (dctSqrt1d2 * (p[1 + row] + p[7 + row]) + 128) >> 8;
- v5 = p[3 + row] << 4;
- v6 = p[5 + row] << 4;
-
- // stage 3
- 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;
+ // A port of poppler's IDCT method which in turn is taken from:
+ // Christoph Loeffler, Adriaan Ligtenberg, George S. Moschytz,
+ // "Practical Fast 1-D DCT Algorithms with 11 Multiplications",
+ // IEEE Intl. Conf. on Acoustics, Speech & Signal Processing, 1989,
+ // 988-991.
+ function quantizeAndInverse(component, blockBufferOffset, p) {
+ var qt = component.quantizationTable;
+ var v0, v1, v2, v3, v4, v5, v6, v7, t;
+ var i;
+
+ // dequant
+ for (i = 0; i < 64; i++)
+ p[i] = component.blocks[blockBufferOffset + i] * qt[i];
+
+ // inverse DCT on rows
+ for (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) {
+ t = (dctSqrt2 * p[0 + row] + 512) >> 10;
+ p[0 + row] = t;
+ p[1 + row] = t;
+ p[2 + row] = t;
+ p[3 + row] = t;
+ p[4 + row] = t;
+ p[5 + row] = t;
+ p[6 + row] = t;
+ p[7 + row] = t;
+ continue;
}
- // inverse DCT on columns
- for (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) {
- t = (dctSqrt2 * p[i+0] + 8192) >> 14;
- p[0*8 + col] = t;
- p[1*8 + col] = t;
- p[2*8 + col] = t;
- p[3*8 + col] = t;
- p[4*8 + col] = t;
- p[5*8 + col] = t;
- p[6*8 + col] = t;
- p[7*8 + col] = t;
- continue;
- }
+ // stage 4
+ v0 = (dctSqrt2 * p[0 + row] + 128) >> 8;
+ v1 = (dctSqrt2 * p[4 + row] + 128) >> 8;
+ v2 = p[2 + row];
+ v3 = p[6 + row];
+ v4 = (dctSqrt1d2 * (p[1 + row] - p[7 + row]) + 128) >> 8;
+ v7 = (dctSqrt1d2 * (p[1 + row] + p[7 + row]) + 128) >> 8;
+ v5 = p[3 + row] << 4;
+ v6 = p[5 + row] << 4;
+
+ // stage 3
+ 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;
+ }
- // stage 4
- v0 = (dctSqrt2 * p[0*8 + col] + 2048) >> 12;
- v1 = (dctSqrt2 * p[4*8 + col] + 2048) >> 12;
- v2 = p[2*8 + col];
- v3 = p[6*8 + col];
- v4 = (dctSqrt1d2 * (p[1*8 + col] - p[7*8 + col]) + 2048) >> 12;
- v7 = (dctSqrt1d2 * (p[1*8 + col] + p[7*8 + col]) + 2048) >> 12;
- v5 = p[3*8 + col];
- v6 = p[5*8 + col];
-
- // stage 3
- 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;
+ // inverse DCT on columns
+ for (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) {
+ t = (dctSqrt2 * p[i+0] + 8192) >> 14;
+ p[0*8 + col] = t;
+ p[1*8 + col] = t;
+ p[2*8 + col] = t;
+ p[3*8 + col] = t;
+ p[4*8 + col] = t;
+ p[5*8 + col] = t;
+ p[6*8 + col] = t;
+ p[7*8 + col] = t;
+ continue;
}
- // convert to 8-bit integers
- for (i = 0; i < 64; ++i) {
- p[i] = clampTo8bit((p[i] + 2056) >> 4);
- }
+ // stage 4
+ v0 = (dctSqrt2 * p[0*8 + col] + 2048) >> 12;
+ v1 = (dctSqrt2 * p[4*8 + col] + 2048) >> 12;
+ v2 = p[2*8 + col];
+ v3 = p[6*8 + col];
+ v4 = (dctSqrt1d2 * (p[1*8 + col] - p[7*8 + col]) + 2048) >> 12;
+ v7 = (dctSqrt1d2 * (p[1*8 + col] + p[7*8 + col]) + 2048) >> 12;
+ v5 = p[3*8 + col];
+ v6 = p[5*8 + col];
+
+ // stage 3
+ 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 (i = 0; i < 64; ++i) {
+ p[i] = clampTo8bit((p[i] + 2056) >> 4);
+ }
+ }
+
+ function buildComponentData(frame, component) {
+ var lines = [];
+ var blocksPerLine = component.blocksPerLine;
+ var blocksPerColumn = component.blocksPerColumn;
+ var samplesPerLine = blocksPerLine << 3;
+ var R = new Int16Array(64);
+
var i, j;
for (var blockRow = 0; blockRow < blocksPerColumn; blockRow++) {
var scanLine = blockRow << 3;
- for (i = 0; i < 8; i++)
+ for (i = 0; i < 8; i++) {
lines.push(new Uint8Array(samplesPerLine));
+ }
for (var blockCol = 0; blockCol < blocksPerLine; blockCol++) {
- quantizeAndInverse(component.blocks[blockRow][blockCol], R);
+ quantizeAndInverse(component,
+ getBlockBufferOffset(component, blockRow, blockCol),
+ R);
var offset = 0, sample = blockCol << 3;
for (j = 0; j < 8; j++) {
var line = lines[scanLine + j];
- for (i = 0; i < 8; i++)
+ for (i = 0; i < 8; i++) {
line[sample + i] = R[offset++];
+ }
}
}
}
@@ -532,60 +544,50 @@ var JpegImage = (function jpegImage() {
}).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 Int16Array(64));
- blocks.push(row);
- }
- component.blocksPerLine = blocksPerLine;
- component.blocksPerColumn = blocksPerColumn;
- component.blocks = blocks;
- }
+ var mcusPerLine = Math.ceil(frame.samplesPerLine / (frame.maxH << 3));
+ var mcusPerColumn = Math.ceil(frame.scanLines / (frame.maxV << 3));
+ for (var i = 0; i < frame.components.length; i++) {
+ component = frame.components[i];
+ 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 blocksBufferSize = 64 * blocksPerColumnForMcu
+ * blocksPerLineForMcu;
+ var blocks = new Int16Array(blocksBufferSize);
+
+ component.blocksPerLine = blocksPerLine;
+ component.blocksPerColumn = blocksPerColumn;
+ component.blocks = blocks;
}
- frame.maxH = maxH;
- frame.maxV = maxV;
frame.mcusPerLine = mcusPerLine;
frame.mcusPerColumn = mcusPerColumn;
}
+
+ var offset = 0, length = data.length;
var jfif = null;
var adobe = null;
var pixels = null;
var frame, resetInterval;
- var quantizationTables = [], frames = [];
+ var quantizationTables = [];
var huffmanTablesAC = [], huffmanTablesDC = [];
var fileMarker = readUint16();
if (fileMarker != 0xFFD8) { // SOI (Start of Image)
@@ -668,6 +670,9 @@ var JpegImage = (function jpegImage() {
case 0xFFC0: // SOF0 (Start of Frame, Baseline DCT)
case 0xFFC1: // SOF1 (Start of Frame, Extended DCT)
case 0xFFC2: // SOF2 (Start of Frame, Progressive DCT)
+ if (frame) {
+ throw "Only single frame JPEGs supported";
+ }
readUint16(); // skip data length
frame = {};
frame.extended = (fileMarker === 0xFFC1);
@@ -675,25 +680,28 @@ var JpegImage = (function jpegImage() {
frame.precision = data[offset++];
frame.scanLines = readUint16();
frame.samplesPerLine = readUint16();
- frame.components = {};
- frame.componentsOrder = [];
+ 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];
- frame.componentsOrder.push(componentId);
- frame.components[componentId] = {
+ var l = frame.components.push({
h: h,
v: v,
quantizationTable: quantizationTables[qId]
- };
+ });
+ frame.componentIds[componentId] = l - 1;
offset += 3;
}
+ frame.maxH = maxH;
+ frame.maxV = maxV;
prepareComponents(frame);
- frames.push(frame);
break;
case 0xFFC4: // DHT (Define Huffman Tables)
@@ -709,7 +717,7 @@ var JpegImage = (function jpegImage() {
huffmanValues[j] = data[offset];
i += 17 + codeLengthSum;
- ((huffmanTableSpec >> 4) === 0 ?
+ ((huffmanTableSpec >> 4) === 0 ?
huffmanTablesDC : huffmanTablesAC)[huffmanTableSpec & 15] =
buildHuffmanTable(codeLengths, huffmanValues);
}
@@ -725,7 +733,8 @@ var JpegImage = (function jpegImage() {
var selectorsCount = data[offset++];
var components = [], component;
for (i = 0; i < selectorsCount; i++) {
- component = frame.components[data[offset++]];
+ var componentIndex = frame.componentIds[data[offset++]];
+ component = frame.components[componentIndex];
var tableSpec = data[offset++];
component.huffmanTableDC = huffmanTablesDC[tableSpec >> 4];
component.huffmanTableAC = huffmanTablesAC[tableSpec & 15];
@@ -752,16 +761,14 @@ var JpegImage = (function jpegImage() {
}
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 i = 0; i < frame.componentsOrder.length; i++) {
- var component = frame.components[frame.componentsOrder[i]];
+ for (var i = 0; i < frame.components.length; i++) {
+ var component = frame.components[i];
this.components.push({
lines: buildComponentData(frame, component),
scaleX: component.h / frame.maxH,
--
Alioth's /usr/local/bin/git-commit-notice on /srv/git.debian.org/git/pkg-javascript/pdf.js.git
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