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Merge pull request #4397 from fkaelberer/FixJPXcolors

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Fix JPX colors
This commit is contained in:
Yury Delendik 2014-03-06 08:57:17 -06:00
commit 1857ced63f
1 changed files with 43 additions and 27 deletions
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src/core/jpx.js
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@ -26,6 +26,10 @@ var JpxImage = (function JpxImageClosure() {
'HL': 1,
'HH': 2
};
var TransformType = {
IRREVERSIBLE: 0,
REVERSIBLE: 1
};
function JpxImage() {
this.failOnCorruptedImage = false;
}
@ -867,7 +871,6 @@ var JpxImage = (function JpxImageClosure() {
function copyCoefficients(coefficients, x0, y0, width, height,
delta, mb, codeblocks, transformation,
segmentationSymbolUsed) {
var r = 0.5; // formula (E-6)
for (var i = 0, ii = codeblocks.length; i < ii; ++i) {
var codeblock = codeblocks[i];
var blockWidth = codeblock.tbx1_ - codeblock.tbx0_;
@ -921,20 +924,16 @@ var JpxImage = (function JpxImageClosure() {
}
var offset = (codeblock.tbx0_ - x0) + (codeblock.tby0_ - y0) * width;
var position = 0;
var n, nb, correction, position = 0;
var irreversible = (transformation === TransformType.IRREVERSIBLE);
var sign = bitModel.coefficentsSign;
var magnitude = bitModel.coefficentsMagnitude;
var bitsDecoded = bitModel.bitsDecoded;
for (var j = 0; j < blockHeight; j++) {
for (var k = 0; k < blockWidth; k++) {
var n = (bitModel.coefficentsSign[position] ? -1 : 1) *
bitModel.coefficentsMagnitude[position];
var nb = bitModel.bitsDecoded[position], correction;
if (transformation === 0 || mb > nb) {
// use r only if transformation is irreversible or
// not all bitplanes were decoded for reversible transformation
n += n < 0 ? n - r : n > 0 ? n + r : 0;
correction = 1 << (mb - nb);
} else {
correction = 1;
}
n = (sign[position] ? -1 : 1) * magnitude[position];
nb = bitsDecoded[position];
correction = (irreversible || mb > nb) ? 1 << (mb - nb) : 1;
coefficients[offset++] = n * correction * delta;
position++;
}
@ -955,6 +954,10 @@ var JpxImage = (function JpxImageClosure() {
var segmentationSymbolUsed = codingStyleParameters.segmentationSymbolUsed;
var precision = context.components[c].precision;
var transformation = codingStyleParameters.transformation;
var transform = transformation === TransformType.IRREVERSIBLE ?
new IrreversibleTransform() : new ReversibleTransform();
var subbandCoefficients = [];
var k = 0, b = 0;
for (var i = 0; i <= decompositionLevelsCount; i++) {
@ -977,8 +980,8 @@ var JpxImage = (function JpxImageClosure() {
var gainLog2 = SubbandsGainLog2[subband.type];
// calulate quantization coefficient (Section E.1.1.1)
var delta = Math.pow(2, (precision + gainLog2) - epsilon) *
(1 + mu / 2048);
var delta = transformation === TransformType.IRREVERSIBLE ?
Math.pow(2, precision + gainLog2 - epsilon) * (1 + mu / 2048) : 1;
var mb = (guardBits + epsilon - 1);
var coefficients = new Float32Array(width * height);
@ -996,9 +999,6 @@ var JpxImage = (function JpxImageClosure() {
}
}
var transformation = codingStyleParameters.transformation;
var transform = transformation === 0 ? new IrreversibleTransform() :
new ReversibleTransform();
var result = transform.calculate(subbandCoefficients,
component.tcx0, component.tcy0);
return {
@ -1024,15 +1024,31 @@ var JpxImage = (function JpxImageClosure() {
// Section G.2.2 Inverse multi component transform
if (tile.codingStyleDefaultParameters.multipleComponentTransform) {
var y0items = result[0].items;
var y1items = result[1].items;
var y2items = result[2].items;
for (var j = 0, jj = y0items.length; j < jj; j++) {
var y0 = y0items[j], y1 = y1items[j], y2 = y2items[j];
var i1 = y0 - ((y2 + y1) >> 2);
y1items[j] = i1;
y0items[j] = y2 + i1;
y2items[j] = y1 + i1;
var component0 = tile.components[0];
var transformation = component0.codingStyleParameters.transformation;
if (transformation === TransformType.IRREVERSIBLE) {
// inverse irreversible multiple component transform
var y0items = result[0].items;
var y1items = result[1].items;
var y2items = result[2].items;
for (var j = 0, jj = y0items.length; j < jj; ++j) {
var y0 = y0items[j], y1 = y1items[j], y2 = y2items[j];
y0items[j] = y0 + 1.402 * y2 + 0.5;
y1items[j] = y0 - 0.34413 * y1 - 0.71414 * y2 + 0.5;
y2items[j] = y0 + 1.772 * y1 + 0.5;
}
} else {
// inverse reversible multiple component transform
var y0items = result[0].items;
var y1items = result[1].items;
var y2items = result[2].items;
for (var j = 0, jj = y0items.length; j < jj; ++j) {
var y0 = y0items[j], y1 = y1items[j], y2 = y2items[j];
var i1 = y0 - ((y2 + y1) >> 2);
y1items[j] = i1;
y0items[j] = y2 + i1;
y2items[j] = y1 + i1;
}
}
}