jpgjs performance tuning
This commit is contained in:
fkaelberer
Yury Delendik
parent
35f5a1ea5e
commit
e874b272bf
204
external/jpgjs/jpg.js
vendored
204
external/jpgjs/jpg.js
vendored
@ -335,17 +335,16 @@ var JpegImage = (function jpegImage() {
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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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var R = new Int32Array(64), r = new Uint8Array(64);
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var R = new Int32Array(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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function quantizeAndInverse(zz, p) {
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var qt = component.quantizationTable;
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var v0, v1, v2, v3, v4, v5, v6, v7, t;
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var p = dataIn;
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var i;
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// dequant
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@ -429,7 +428,7 @@ var JpegImage = (function jpegImage() {
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if (p[1*8 + col] == 0 && p[2*8 + col] == 0 && p[3*8 + col] == 0 &&
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p[4*8 + col] == 0 && p[5*8 + col] == 0 && p[6*8 + col] == 0 &&
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p[7*8 + col] == 0) {
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t = (dctSqrt2 * dataIn[i+0] + 8192) >> 14;
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t = (dctSqrt2 * p[i+0] + 8192) >> 14;
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p[0*8 + col] = t;
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p[1*8 + col] = t;
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p[2*8 + col] = t;
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@ -492,8 +491,7 @@ var JpegImage = (function jpegImage() {
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// convert to 8-bit integers
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for (i = 0; i < 64; ++i) {
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var sample = 128 + ((p[i] + 8) >> 4);
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dataOut[i] = sample < 0 ? 0 : sample > 0xFF ? 0xFF : sample;
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p[i] = clampTo8bit((p[i] + 2056) >> 4);
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}
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}
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@ -503,13 +501,13 @@ var JpegImage = (function jpegImage() {
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for (i = 0; i < 8; i++)
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lines.push(new Uint8Array(samplesPerLine));
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for (var blockCol = 0; blockCol < blocksPerLine; blockCol++) {
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quantizeAndInverse(component.blocks[blockRow][blockCol], r, R);
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quantizeAndInverse(component.blocks[blockRow][blockCol], R);
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var offset = 0, sample = blockCol << 3;
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for (j = 0; j < 8; j++) {
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var line = lines[scanLine + j];
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for (i = 0; i < 8; i++)
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line[sample + i] = r[offset++];
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line[sample + i] = R[offset++];
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}
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}
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}
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@ -570,7 +568,7 @@ var JpegImage = (function jpegImage() {
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for (var i = 0; i < blocksPerColumnForMcu; i++) {
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var row = [];
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for (var j = 0; j < blocksPerLineForMcu; j++)
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row.push(new Int32Array(64));
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row.push(new Int16Array(64));
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blocks.push(row);
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}
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component.blocksPerLine = blocksPerLine;
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@ -774,41 +772,35 @@ var JpegImage = (function jpegImage() {
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getData: function getData(width, height) {
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var scaleX = this.width / width, scaleY = this.height / height;
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var component1, component2, component3, component4;
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var component1Line, component2Line, component3Line, component4Line;
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var x, y;
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var component, componentLine, componentScaleX, componentScaleY;
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var x, y, i;
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var offset = 0;
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var Y, Cb, Cr, K, C, M, Ye, R, G, B;
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var colorTransform;
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var dataLength = width * height * this.components.length;
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var numComponents = this.components.length;
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var dataLength = width * height * numComponents;
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var data = new Uint8Array(dataLength);
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switch (this.components.length) {
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case 1:
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component1 = this.components[0];
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for (y = 0; y < height; y++) {
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component1Line = component1.lines[0 | (y * component1.scaleY * scaleY)];
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for (x = 0; x < width; x++) {
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Y = component1Line[0 | (x * component1.scaleX * scaleX)];
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data[offset++] = Y;
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}
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// First construct image data ...
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for (i = 0; i < numComponents; i++) {
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component = this.components[i];
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componentScaleX = component.scaleX * scaleX;
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componentScaleY = component.scaleY * scaleY;
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offset = i;
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for (y = 0; y < height; y++) {
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componentLine = component.lines[0 | (y * componentScaleY)];
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for (x = 0; x < width; x++) {
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data[offset] = componentLine[0 | (x * componentScaleX)];
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offset += numComponents;
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}
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break;
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case 2:
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// PDF might compress two component data in custom colorspace
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component1 = this.components[0];
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component2 = this.components[1];
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for (y = 0; y < height; y++) {
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component1Line = component1.lines[0 | (y * component1.scaleY * scaleY)];
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component2Line = component2.lines[0 | (y * component2.scaleY * scaleY)];
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for (x = 0; x < width; x++) {
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Y = component1Line[0 | (x * component1.scaleX * scaleX)];
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data[offset++] = Y;
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Y = component2Line[0 | (x * component2.scaleX * scaleX)];
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data[offset++] = Y;
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}
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}
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break;
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}
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}
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// ... then transform colors, if necessary
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switch (numComponents) {
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case 1: case 2: break;
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// no color conversion for one or two compoenents
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case 3:
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// The default transform for three components is true
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colorTransform = true;
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@ -818,31 +810,19 @@ var JpegImage = (function jpegImage() {
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else if (typeof this.colorTransform !== 'undefined')
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colorTransform = !!this.colorTransform;
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component1 = this.components[0];
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component2 = this.components[1];
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component3 = this.components[2];
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for (y = 0; y < height; y++) {
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component1Line = component1.lines[0 | (y * component1.scaleY * scaleY)];
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component2Line = component2.lines[0 | (y * component2.scaleY * scaleY)];
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component3Line = component3.lines[0 | (y * component3.scaleY * scaleY)];
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for (x = 0; x < width; x++) {
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if (!colorTransform) {
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R = component1Line[0 | (x * component1.scaleX * scaleX)];
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G = component2Line[0 | (x * component2.scaleX * scaleX)];
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B = component3Line[0 | (x * component3.scaleX * scaleX)];
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} else {
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Y = component1Line[0 | (x * component1.scaleX * scaleX)];
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Cb = component2Line[0 | (x * component2.scaleX * scaleX)];
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Cr = component3Line[0 | (x * component3.scaleX * scaleX)];
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if (colorTransform) {
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for (i = 0; i < dataLength; i += numComponents) {
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Y = data[i ];
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Cb = data[i + 1];
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Cr = data[i + 2];
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R = clampTo8bit(Y + 1.402 * (Cr - 128));
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G = clampTo8bit(Y - 0.3441363 * (Cb - 128) - 0.71413636 * (Cr - 128));
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B = clampTo8bit(Y + 1.772 * (Cb - 128));
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}
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R = clampTo8bit(Y + 1.402 * (Cr - 128));
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G = clampTo8bit(Y - 0.3441363 * (Cb - 128) - 0.71413636 * (Cr - 128));
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B = clampTo8bit(Y + 1.772 * (Cb - 128));
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data[offset++] = R;
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data[offset++] = G;
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data[offset++] = B;
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data[i ] = R;
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data[i + 1] = G;
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data[i + 2] = B;
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}
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}
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break;
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@ -855,35 +835,20 @@ var JpegImage = (function jpegImage() {
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else if (typeof this.colorTransform !== 'undefined')
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colorTransform = !!this.colorTransform;
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component1 = this.components[0];
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component2 = this.components[1];
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component3 = this.components[2];
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component4 = this.components[3];
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for (y = 0; y < height; y++) {
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component1Line = component1.lines[0 | (y * component1.scaleY * scaleY)];
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component2Line = component2.lines[0 | (y * component2.scaleY * scaleY)];
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component3Line = component3.lines[0 | (y * component3.scaleY * scaleY)];
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component4Line = component4.lines[0 | (y * component4.scaleY * scaleY)];
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for (x = 0; x < width; x++) {
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if (!colorTransform) {
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C = component1Line[0 | (x * component1.scaleX * scaleX)];
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M = component2Line[0 | (x * component2.scaleX * scaleX)];
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Ye = component3Line[0 | (x * component3.scaleX * scaleX)];
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K = component4Line[0 | (x * component4.scaleX * scaleX)];
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} else {
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Y = component1Line[0 | (x * component1.scaleX * scaleX)];
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Cb = component2Line[0 | (x * component2.scaleX * scaleX)];
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Cr = component3Line[0 | (x * component3.scaleX * scaleX)];
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K = component4Line[0 | (x * component4.scaleX * scaleX)];
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if (colorTransform) {
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for (i = 0; i < dataLength; i += numComponents) {
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Y = data[i];
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Cb = data[i + 1];
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Cr = data[i + 2];
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C = 255 - clampTo8bit(Y + 1.402 * (Cr - 128));
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M = 255 - clampTo8bit(Y - 0.3441363 * (Cb - 128) - 0.71413636 * (Cr - 128));
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Ye = 255 - clampTo8bit(Y + 1.772 * (Cb - 128));
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}
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data[offset++] = C;
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data[offset++] = M;
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data[offset++] = Ye;
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data[offset++] = K;
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C = 255 - clampTo8bit(Y + 1.402 * (Cr - 128));
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M = 255 - clampTo8bit(Y - 0.3441363 * (Cb - 128) - 0.71413636 * (Cr - 128));
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Ye = 255 - clampTo8bit(Y + 1.772 * (Cb - 128));
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data[i ] = C;
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data[i + 1] = M;
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data[i + 2] = Ye;
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// K is unchanged
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}
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}
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break;
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@ -894,54 +859,49 @@ var JpegImage = (function jpegImage() {
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},
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copyToImageData: function copyToImageData(imageData) {
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var width = imageData.width, height = imageData.height;
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var imageDataBytes = width * height * 4;
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var imageDataArray = imageData.data;
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var data = this.getData(width, height);
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var i = 0, j = 0, x, y;
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var i = 0, j = 0;
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var Y, K, C, M, R, G, B;
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switch (this.components.length) {
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case 1:
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for (y = 0; y < height; y++) {
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for (x = 0; x < width; x++) {
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Y = data[i++];
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while (j < imageDataBytes) {
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Y = data[i++];
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imageDataArray[j++] = Y;
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imageDataArray[j++] = Y;
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imageDataArray[j++] = Y;
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imageDataArray[j++] = 255;
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}
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imageDataArray[j++] = Y;
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imageDataArray[j++] = Y;
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imageDataArray[j++] = Y;
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imageDataArray[j++] = 255;
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}
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break;
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case 3:
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for (y = 0; y < height; y++) {
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for (x = 0; x < width; x++) {
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R = data[i++];
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G = data[i++];
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B = data[i++];
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while (j < imageDataBytes) {
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R = data[i++];
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G = data[i++];
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B = data[i++];
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imageDataArray[j++] = R;
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imageDataArray[j++] = G;
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imageDataArray[j++] = B;
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imageDataArray[j++] = 255;
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}
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imageDataArray[j++] = R;
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imageDataArray[j++] = G;
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imageDataArray[j++] = B;
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imageDataArray[j++] = 255;
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}
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break;
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case 4:
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for (y = 0; y < height; y++) {
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for (x = 0; x < width; x++) {
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C = data[i++];
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M = data[i++];
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Y = data[i++];
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K = data[i++];
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while (j < imageDataBytes) {
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C = data[i++];
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M = data[i++];
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Y = data[i++];
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K = data[i++];
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R = 255 - clampTo8bit(C * (1 - K / 255) + K);
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G = 255 - clampTo8bit(M * (1 - K / 255) + K);
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B = 255 - clampTo8bit(Y * (1 - K / 255) + K);
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R = 255 - clampTo8bit(C * (1 - K / 255) + K);
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G = 255 - clampTo8bit(M * (1 - K / 255) + K);
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B = 255 - clampTo8bit(Y * (1 - K / 255) + K);
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imageDataArray[j++] = R;
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imageDataArray[j++] = G;
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imageDataArray[j++] = B;
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imageDataArray[j++] = 255;
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}
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imageDataArray[j++] = R;
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imageDataArray[j++] = G;
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imageDataArray[j++] = B;
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imageDataArray[j++] = 255;
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}
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break;
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default:
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