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Merge pull request #4568 from p01/JPX_optimization

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Jpx optimization
This commit is contained in:
Yury Delendik 2014-04-09 17:25:11 -05:00
commit af536353d5
1 changed files with 182 additions and 190 deletions
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src/core/jpx.js
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@ -108,7 +108,7 @@ var JpxImage = (function JpxImageClosure() {
// Image and tile size (SIZ) // Image and tile size (SIZ)
if (code == 0xFF51) { if (code == 0xFF51) {
stream.skip(4); stream.skip(4);
var Xsiz = stream.getUint32(); // Byte 4 var Xsiz = stream.getUint32(); // Byte 4
var Ysiz = stream.getUint32(); // Byte 8 var Ysiz = stream.getUint32(); // Byte 8
var XOsiz = stream.getUint32(); // Byte 12 var XOsiz = stream.getUint32(); // Byte 12
var YOsiz = stream.getUint32(); // Byte 16 var YOsiz = stream.getUint32(); // Byte 16
@ -117,7 +117,7 @@ var JpxImage = (function JpxImageClosure() {
this.width = Xsiz - XOsiz; this.width = Xsiz - XOsiz;
this.height = Ysiz - YOsiz; this.height = Ysiz - YOsiz;
this.componentsCount = Csiz; this.componentsCount = Csiz;
// Results are always returned as UInt8Arrays // Results are always returned as UInt8Arrays
this.bitsPerComponent = 8; this.bitsPerComponent = 8;
return; return;
} }
@ -491,10 +491,10 @@ var JpxImage = (function JpxImageClosure() {
var ycb_ = dimensions.ycb_; var ycb_ = dimensions.ycb_;
var codeblockWidth = 1 << xcb_; var codeblockWidth = 1 << xcb_;
var codeblockHeight = 1 << ycb_; var codeblockHeight = 1 << ycb_;
var cbx0 = Math.floor(subband.tbx0 / codeblockWidth); var cbx0 = subband.tbx0 >> xcb_;
var cby0 = Math.floor(subband.tby0 / codeblockHeight); var cby0 = subband.tby0 >> ycb_;
var cbx1 = Math.ceil(subband.tbx1 / codeblockWidth); var cbx1 = (subband.tbx1 + codeblockWidth - 1) >> xcb_;
var cby1 = Math.ceil(subband.tby1 / codeblockHeight); var cby1 = (subband.tby1 + codeblockHeight - 1) >> ycb_;
var precinctParameters = subband.resolution.precinctParameters; var precinctParameters = subband.resolution.precinctParameters;
var codeblocks = []; var codeblocks = [];
var precincts = []; var precincts = [];
@ -528,13 +528,18 @@ var JpxImage = (function JpxImageClosure() {
codeblock.Lblock = 3; codeblock.Lblock = 3;
codeblocks.push(codeblock); codeblocks.push(codeblock);
// building precinct for the sub-band // building precinct for the sub-band
var precinct; var precinct = precincts[precinctNumber];
if (precinctNumber in precincts) { if (precinct !== undefined) {
precinct = precincts[precinctNumber]; if (i < precinct.cbxMin) {
precinct.cbxMin = Math.min(precinct.cbxMin, i); precinct.cbxMin = i;
precinct.cbyMin = Math.min(precinct.cbyMin, j); } else if (i > precinct.cbxMax) {
precinct.cbxMax = Math.max(precinct.cbxMax, i); precinct.cbxMax = i;
precinct.cbyMax = Math.max(precinct.cbyMax, j); }
if (j < precinct.cbyMin) {
precinct.cbxMin = j;
} else if (j > precinct.cbyMax) {
precinct.cbyMax = j;
}
} else { } else {
precincts[precinctNumber] = precinct = { precincts[precinctNumber] = precinct = {
cbxMin: i, cbxMin: i,
@ -553,10 +558,6 @@ var JpxImage = (function JpxImageClosure() {
numcodeblockhigh: cby1 - cby1 + 1 numcodeblockhigh: cby1 - cby1 + 1
}; };
subband.codeblocks = codeblocks; subband.codeblocks = codeblocks;
for (var i = 0, ii = codeblocks.length; i < ii; i++) {
var codeblock = codeblocks[i];
var precinctNumber = codeblock.precinctNumber;
}
subband.precincts = precincts; subband.precincts = precincts;
} }
function createPacket(resolution, precinctNumber, layerNumber) { function createPacket(resolution, precinctNumber, layerNumber) {
@ -972,13 +973,18 @@ var JpxImage = (function JpxImageClosure() {
var magnitudeCorrection = reversible ? 0 : 0.5; var magnitudeCorrection = reversible ? 0 : 0.5;
for (var j = 0; j < blockHeight; j++) { for (var j = 0; j < blockHeight; j++) {
for (var k = 0; k < blockWidth; k++) { for (var k = 0; k < blockWidth; k++) {
var mag = magnitude[position]; n = magnitude[position];
if (mag !== 0) { if (n !== 0) {
n = sign[position] ? -(mag + magnitudeCorrection) : n = (n + magnitudeCorrection) * delta;
(mag + magnitudeCorrection); if (sign[position] !== 0) {
n = -n;
}
nb = bitsDecoded[position]; nb = bitsDecoded[position];
correction = (irreversible || mb > nb) ? 1 << (mb - nb) : 1; if (irreversible || mb > nb) {
coefficients[offset] = n * correction * delta; coefficients[offset] = n * (1 << (mb - nb));
} else {
coefficients[offset] = n;
}
} }
offset++; offset++;
position++; position++;
@ -1076,10 +1082,10 @@ var JpxImage = (function JpxImageClosure() {
var y1items = result[1].items; var y1items = result[1].items;
var y2items = result[2].items; var y2items = result[2].items;
for (var j = 0, jj = y0items.length; j < jj; ++j) { for (var j = 0, jj = y0items.length; j < jj; ++j) {
var y0 = y0items[j], y1 = y1items[j], y2 = y2items[j]; var y0 = y0items[j] + 0.5, y1 = y1items[j], y2 = y2items[j];
y0items[j] = y0 + 1.402 * y2 + 0.5; y0items[j] = y0 + 1.402 * y2;
y1items[j] = y0 - 0.34413 * y1 - 0.71414 * y2 + 0.5; y1items[j] = y0 - 0.34413 * y1 - 0.71414 * y2;
y2items[j] = y0 + 1.772 * y1 + 0.5; y2items[j] = y0 + 1.772 * y1;
} }
} else { } else {
// inverse reversible multiple component transform // inverse reversible multiple component transform
@ -1096,32 +1102,18 @@ var JpxImage = (function JpxImageClosure() {
} }
} }
// Section G.1 DC level shifting to unsigned component values
for (var c = 0; c < componentsCount; c++) {
var component = components[c];
if (component.isSigned) {
continue;
}
var offset = 1 << (component.precision - 1);
var tileImage = result[c];
var items = tileImage.items;
for (var j = 0, jj = items.length; j < jj; j++) {
items[j] += offset;
}
}
// To simplify things: shift and clamp output to 8 bit unsigned // To simplify things: shift and clamp output to 8 bit unsigned
for (var c = 0; c < componentsCount; c++) { for (var c = 0; c < componentsCount; c++) {
var component = components[c]; var component = components[c];
var offset = component.isSigned ? 128 : 0;
var shift = component.precision - 8; var shift = component.precision - 8;
var tileImage = result[c]; var tileImage = result[c];
var items = tileImage.items; var items = tileImage.items;
var data = new Uint8Array(items.length); var data = new Uint8Array(items.length);
var low = -(128 << shift);
var high = 127 << shift;
for (var j = 0, jj = items.length; j < jj; j++) { for (var j = 0, jj = items.length; j < jj; j++) {
var value = (items[j] >> shift) + offset; var val = items[j];
data[j] = value < 0 ? 0 : value > 255 ? 255 : value; data[j] = val <= low ? 0 : val >= high ? 255 : (val >> shift) + 128;
} }
result[c].items = data; result[c].items = data;
} }
@ -1311,31 +1303,6 @@ var JpxImage = (function JpxImageClosure() {
8, 0, 8, 8, 8, 0, 8, 8, 8, 0, 0, 0, 0, 0, 8, 8, 8, 0, 8, 8, 8, 0, 8, 8, 8 8, 0, 8, 8, 8, 0, 8, 8, 8, 0, 0, 0, 0, 0, 8, 8, 8, 0, 8, 8, 8, 0, 8, 8, 8
]); ]);
// Table D-2
function calcSignContribution(significance0, sign0, significance1, sign1) {
if (significance1) {
if (!sign1) {
return significance0 ? (!sign0 ? 1 : 0) : 1;
} else {
return significance0 ? (!sign0 ? 0 : -1) : -1;
}
} else {
return significance0 ? (!sign0 ? 1 : -1) : 0;
}
}
// Table D-3
var SignContextLabels = [
{contextLabel: 13, xorBit: 0},
{contextLabel: 12, xorBit: 0},
{contextLabel: 11, xorBit: 0},
{contextLabel: 10, xorBit: 0},
{contextLabel: 9, xorBit: 0},
{contextLabel: 10, xorBit: 1},
{contextLabel: 11, xorBit: 1},
{contextLabel: 12, xorBit: 1},
{contextLabel: 13, xorBit: 1}
];
function BitModel(width, height, subband, zeroBitPlanes) { function BitModel(width, height, subband, zeroBitPlanes) {
this.width = width; this.width = width;
this.height = height; this.height = height;
@ -1352,9 +1319,11 @@ var JpxImage = (function JpxImageClosure() {
this.coefficentsMagnitude = new Uint32Array(coefficientCount); this.coefficentsMagnitude = new Uint32Array(coefficientCount);
this.processingFlags = new Uint8Array(coefficientCount); this.processingFlags = new Uint8Array(coefficientCount);
var bitsDecoded = new Uint8Array(this.width * this.height); var bitsDecoded = new Uint8Array(coefficientCount);
for (var i = 0, ii = bitsDecoded.length; i < ii; i++) { if (zeroBitPlanes !== 0) {
bitsDecoded[i] = zeroBitPlanes; for (var i = 0; i < coefficientCount; i++) {
bitsDecoded[i] = zeroBitPlanes;
}
} }
this.bitsDecoded = bitsDecoded; this.bitsDecoded = bitsDecoded;
@ -1366,7 +1335,7 @@ var JpxImage = (function JpxImageClosure() {
this.decoder = decoder; this.decoder = decoder;
}, },
reset: function BitModel_reset() { reset: function BitModel_reset() {
// We have 17 contexts that are accessed via context labels, // We have 17 contexts that are accessed via context labels,
// plus the uniform and runlength context. // plus the uniform and runlength context.
this.contexts = new Int8Array(19); this.contexts = new Int8Array(19);
@ -1377,32 +1346,38 @@ var JpxImage = (function JpxImageClosure() {
this.contexts[RUNLENGTH_CONTEXT] = (3 << 1) | 0; this.contexts[RUNLENGTH_CONTEXT] = (3 << 1) | 0;
}, },
setNeighborsSignificance: setNeighborsSignificance:
function BitModel_setNeighborsSignificance(row, column) { function BitModel_setNeighborsSignificance(row, column, index) {
var neighborsSignificance = this.neighborsSignificance; var neighborsSignificance = this.neighborsSignificance;
var width = this.width, height = this.height; var width = this.width, height = this.height;
var index = row * width + column; var left = (column > 0);
var right = (column + 1 < width);
if (row > 0) { if (row > 0) {
if (column > 0) { var i = index - width;
neighborsSignificance[index - width - 1] += 0x10; if (left) {
neighborsSignificance[i - 1] += 0x10;
} }
if (column + 1 < width) { if (right) {
neighborsSignificance[index - width + 1] += 0x10; neighborsSignificance[i + 1] += 0x10;
} }
neighborsSignificance[index - width] += 0x04; neighborsSignificance[i] += 0x04;
} }
if (row + 1 < height) { if (row + 1 < height) {
if (column > 0) { var i = index + width;
neighborsSignificance[index + width - 1] += 0x10; if (left) {
neighborsSignificance[i - 1] += 0x10;
} }
if (column + 1 < width) { if (right) {
neighborsSignificance[index + width + 1] += 0x10; neighborsSignificance[i + 1] += 0x10;
} }
neighborsSignificance[index + width] += 0x04; neighborsSignificance[i] += 0x04;
} }
if (column > 0) {
if (left) {
neighborsSignificance[index - 1] += 0x01; neighborsSignificance[index - 1] += 0x01;
} }
if (column + 1 < width) { if (right) {
neighborsSignificance[index + 1] += 0x01; neighborsSignificance[index + 1] += 0x01;
} }
neighborsSignificance[index] |= 0x80; neighborsSignificance[index] |= 0x80;
@ -1419,13 +1394,9 @@ var JpxImage = (function JpxImageClosure() {
var contexts = this.contexts; var contexts = this.contexts;
var labels = this.contextLabelTable; var labels = this.contextLabelTable;
var bitsDecoded = this.bitsDecoded; var bitsDecoded = this.bitsDecoded;
// clear processed flag
var processedInverseMask = ~1; var processedInverseMask = ~1;
var processedMask = 1; var processedMask = 1;
var firstMagnitudeBitMask = 2; var firstMagnitudeBitMask = 2;
for (var q = 0, qq = width * height; q < qq; q++) {
processingFlags[q] &= processedInverseMask;
}
for (var i0 = 0; i0 < height; i0 += 4) { for (var i0 = 0; i0 < height; i0 += 4) {
for (var j = 0; j < width; j++) { for (var j = 0; j < width; j++) {
@ -1435,6 +1406,8 @@ var JpxImage = (function JpxImageClosure() {
if (i >= height) { if (i >= height) {
break; break;
} }
// clear processed flag first
processingFlags[index] &= processedInverseMask;
if (coefficentsMagnitude[index] || if (coefficentsMagnitude[index] ||
!neighborsSignificance[index]) { !neighborsSignificance[index]) {
@ -1444,10 +1417,10 @@ var JpxImage = (function JpxImageClosure() {
var contextLabel = labels[neighborsSignificance[index]]; var contextLabel = labels[neighborsSignificance[index]];
var decision = decoder.readBit(contexts, contextLabel); var decision = decoder.readBit(contexts, contextLabel);
if (decision) { if (decision) {
var sign = this.decodeSignBit(i, j); var sign = this.decodeSignBit(i, j, index);
coefficentsSign[index] = sign; coefficentsSign[index] = sign;
coefficentsMagnitude[index] = 1; coefficentsMagnitude[index] = 1;
this.setNeighborsSignificance(i, j); this.setNeighborsSignificance(i, j, index);
processingFlags[index] |= firstMagnitudeBitMask; processingFlags[index] |= firstMagnitudeBitMask;
} }
bitsDecoded[index]++; bitsDecoded[index]++;
@ -1456,27 +1429,55 @@ var JpxImage = (function JpxImageClosure() {
} }
} }
}, },
decodeSignBit: function BitModel_decodeSignBit(row, column) { decodeSignBit: function BitModel_decodeSignBit(row, column, index) {
var width = this.width, height = this.height; var width = this.width, height = this.height;
var index = row * width + column;
var coefficentsMagnitude = this.coefficentsMagnitude; var coefficentsMagnitude = this.coefficentsMagnitude;
var coefficentsSign = this.coefficentsSign; var coefficentsSign = this.coefficentsSign;
var horizontalContribution = calcSignContribution( var contribution, sign0, sign1, significance1;
column > 0 && coefficentsMagnitude[index - 1],
coefficentsSign[index - 1],
column + 1 < width && coefficentsMagnitude[index + 1],
coefficentsSign[index + 1]);
var verticalContribution = calcSignContribution(
row > 0 && coefficentsMagnitude[index - width],
coefficentsSign[index - width],
row + 1 < height && coefficentsMagnitude[index + width],
coefficentsSign[index + width]);
var contextLabelAndXor = SignContextLabels[ // calculate horizontal contribution
3 * (1 - horizontalContribution) + (1 - verticalContribution)]; significance1 = (column > 0 && coefficentsMagnitude[index - 1] !== 0);
var contextLabel = contextLabelAndXor.contextLabel; if (column + 1 < width && coefficentsMagnitude[index + 1] !== 0) {
var decoded = this.decoder.readBit(this.contexts, contextLabel); sign1 = coefficentsSign[index + 1];
return decoded ^ contextLabelAndXor.xorBit; if (significance1) {
sign0 = coefficentsSign[index - 1];
contribution = 1 - sign1 - sign0;
} else {
contribution = 1 - sign1 - sign1;
}
} else if (significance1) {
sign0 = coefficentsSign[index - 1];
contribution = 1 - sign0 - sign0;
} else {
contribution = 0;
}
var horizontalContribution = 3 * contribution;
// calculate vertical contribution and combine with the horizontal
significance1 = (row > 0 && coefficentsMagnitude[index - width] !== 0);
if (row + 1 < height && coefficentsMagnitude[index + width] !== 0) {
sign1 = coefficentsSign[index + width];
if (significance1) {
sign0 = coefficentsSign[index - width];
contribution = 1 - sign1 - sign0 + horizontalContribution;
} else {
contribution = 1 - sign1 - sign1 + horizontalContribution;
}
} else if (significance1) {
sign0 = coefficentsSign[index - width];
contribution = 1 - sign0 - sign0 + horizontalContribution;
} else {
contribution = horizontalContribution;
}
if (contribution >= 0) {
var contextLabel = 9 + contribution;
var decoded = this.decoder.readBit(this.contexts, contextLabel);
} else {
var contextLabel = 9 - contribution;
var decoded = this.decoder.readBit(this.contexts, contextLabel) ^ 1;
}
return decoded;
}, },
runMagnitudeRefinementPass: runMagnitudeRefinementPass:
function BitModel_runMagnitudeRefinementPass() { function BitModel_runMagnitudeRefinementPass() {
@ -1489,14 +1490,13 @@ var JpxImage = (function JpxImageClosure() {
var processingFlags = this.processingFlags; var processingFlags = this.processingFlags;
var processedMask = 1; var processedMask = 1;
var firstMagnitudeBitMask = 2; var firstMagnitudeBitMask = 2;
for (var i0 = 0; i0 < height; i0 += 4) { var length = width * height;
var width4 = width * 4;
for (var index0 = 0, indexNext; index0 < length; index0 = indexNext) {
indexNext = Math.min(length, index0 + width4);
for (var j = 0; j < width; j++) { for (var j = 0; j < width; j++) {
for (var i1 = 0; i1 < 4; i1++) { for (var index = index0 + j; index < indexNext; index += width) {
var i = i0 + i1;
if (i >= height) {
break;
}
var index = i * width + j;
// significant but not those that have just become // significant but not those that have just become
if (!coefficentsMagnitude[index] || if (!coefficentsMagnitude[index] ||
@ -1506,12 +1506,10 @@ var JpxImage = (function JpxImageClosure() {
var contextLabel = 16; var contextLabel = 16;
if ((processingFlags[index] & firstMagnitudeBitMask) !== 0) { if ((processingFlags[index] & firstMagnitudeBitMask) !== 0) {
processingFlags[i * width + j] ^= firstMagnitudeBitMask; processingFlags[index] ^= firstMagnitudeBitMask;
// first refinement // first refinement
var significance = neighborsSignificance[index]; var significance = neighborsSignificance[index] & 127;
var sumOfSignificance = (significance & 3) + contextLabel = significance === 0 ? 15 : 14;
((significance >> 2) & 3) + ((significance >> 4) & 7);
contextLabel = sumOfSignificance >= 1 ? 15 : 14;
} }
var bit = decoder.readBit(contexts, contextLabel); var bit = decoder.readBit(contexts, contextLabel);
@ -1570,10 +1568,10 @@ var JpxImage = (function JpxImageClosure() {
i = i0 + i1; i = i0 + i1;
index += i1 * width; index += i1 * width;
var sign = this.decodeSignBit(i, j); var sign = this.decodeSignBit(i, j, index);
coefficentsSign[index] = sign; coefficentsSign[index] = sign;
coefficentsMagnitude[index] = 1; coefficentsMagnitude[index] = 1;
this.setNeighborsSignificance(i, j); this.setNeighborsSignificance(i, j, index);
processingFlags[index] |= firstMagnitudeBitMask; processingFlags[index] |= firstMagnitudeBitMask;
index = index0; index = index0;
@ -1597,10 +1595,10 @@ var JpxImage = (function JpxImageClosure() {
var contextLabel = labels[neighborsSignificance[index]]; var contextLabel = labels[neighborsSignificance[index]];
var decision = decoder.readBit(contexts, contextLabel); var decision = decoder.readBit(contexts, contextLabel);
if (decision == 1) { if (decision == 1) {
var sign = this.decodeSignBit(i, j); var sign = this.decodeSignBit(i, j, index);
coefficentsSign[index] = sign; coefficentsSign[index] = sign;
coefficentsMagnitude[index] = 1; coefficentsMagnitude[index] = 1;
this.setNeighborsSignificance(i, j); this.setNeighborsSignificance(i, j, index);
processingFlags[index] |= firstMagnitudeBitMask; processingFlags[index] |= firstMagnitudeBitMask;
} }
bitsDecoded[index]++; bitsDecoded[index]++;
@ -1631,7 +1629,7 @@ var JpxImage = (function JpxImageClosure() {
Transform.prototype.calculate = Transform.prototype.calculate =
function transformCalculate(subbands, u0, v0) { function transformCalculate(subbands, u0, v0) {
var ll = subbands[0]; var ll = subbands[0];
for (var i = 1, ii = subbands.length, j = 1; i < ii; i += 3, j++) { for (var i = 1, ii = subbands.length; i < ii; i += 3) {
ll = this.iterate(ll, subbands[i], subbands[i + 1], ll = this.iterate(ll, subbands[i], subbands[i + 1],
subbands[i + 2], u0, v0); subbands[i + 2], u0, v0);
} }
@ -1692,21 +1690,24 @@ var JpxImage = (function JpxImageClosure() {
var rowBuffer = new Float32Array(width + 2 * bufferPadding); var rowBuffer = new Float32Array(width + 2 * bufferPadding);
// Section F.3.4 HOR_SR // Section F.3.4 HOR_SR
for (var v = 0; v < height; v++) { if (width === 1) {
if (width == 1) { // if width = 1, when u0 even keep items as is, when odd divide by 2
// if width = 1, when u0 even keep items as is, when odd divide by 2 if ((u0 & 1) !== 0) {
if ((u0 % 1) !== 0) { for (var v = 0, k = 0; v < height; v++, k += width) {
items[v * width] /= 2; items[k] *= 0.5;
} }
continue;
} }
k = v * width; } else {
rowBuffer.set(items.subarray(k, k + width), bufferPadding); for (var v = 0, k = 0; v < height; v++, k += width) {
rowBuffer.set(items.subarray(k, k + width), bufferPadding);
this.extend(rowBuffer, bufferPadding, width); this.extend(rowBuffer, bufferPadding, width);
this.filter(rowBuffer, bufferPadding, width, u0, rowBuffer); this.filter(rowBuffer, bufferPadding, width, u0, rowBuffer);
items.set(rowBuffer.subarray(bufferPadding, bufferPadding + width), k); items.set(
rowBuffer.subarray(bufferPadding, bufferPadding + width),
k);
}
} }
// Accesses to the items array can take long, because it may not fit into // Accesses to the items array can take long, because it may not fit into
@ -1723,37 +1724,38 @@ var JpxImage = (function JpxImageClosure() {
var b, currentBuffer = 0, ll = bufferPadding + height; var b, currentBuffer = 0, ll = bufferPadding + height;
// Section F.3.5 VER_SR // Section F.3.5 VER_SR
for (var u = 0; u < width; u++) { if (height === 1) {
if (height == 1) {
// if height = 1, when v0 even keep items as is, when odd divide by 2 // if height = 1, when v0 even keep items as is, when odd divide by 2
if ((v0 % 1) !== 0) { if ((v0 & 1) !== 0) {
items[u] /= 2; for (var u = 0; u < width; u++) {
items[u] *= 0.5;
} }
continue;
} }
} else {
// if we ran out of buffers, copy several image columns at once for (var u = 0; u < width; u++) {
if (currentBuffer === 0) { // if we ran out of buffers, copy several image columns at once
numBuffers = Math.min(width - u, numBuffers); if (currentBuffer === 0) {
for (k = u, l = bufferPadding; l < ll; k += width, l++) { numBuffers = Math.min(width - u, numBuffers);
for (b = 0; b < numBuffers; b++) { for (k = u, l = bufferPadding; l < ll; k += width, l++) {
colBuffers[b][l] = items[k + b]; for (b = 0; b < numBuffers; b++) {
colBuffers[b][l] = items[k + b];
}
} }
currentBuffer = numBuffers;
} }
currentBuffer = numBuffers;
}
currentBuffer--; currentBuffer--;
var buffer = colBuffers[currentBuffer]; var buffer = colBuffers[currentBuffer];
this.extend(buffer, bufferPadding, height); this.extend(buffer, bufferPadding, height);
this.filter(buffer, bufferPadding, height, v0, buffer); this.filter(buffer, bufferPadding, height, v0, buffer);
// If this is last buffer in this group of buffers, flush all buffers. // If this is last buffer in this group of buffers, flush all buffers.
if (currentBuffer === 0) { if (currentBuffer === 0) {
k = u - numBuffers + 1; k = u - numBuffers + 1;
for (l = bufferPadding; l < ll; k += width, l++) { for (l = bufferPadding; l < ll; k += width, l++) {
for (b = 0; b < numBuffers; b++) { for (b = 0; b < numBuffers; b++) {
items[k + b] = colBuffers[b][l]; items[k + b] = colBuffers[b][l];
}
} }
} }
} }
@ -1777,9 +1779,8 @@ var JpxImage = (function JpxImageClosure() {
IrreversibleTransform.prototype = Object.create(Transform.prototype); IrreversibleTransform.prototype = Object.create(Transform.prototype);
IrreversibleTransform.prototype.filter = IrreversibleTransform.prototype.filter =
function irreversibleTransformFilter(y, offset, length, i0, x) { function irreversibleTransformFilter(y, offset, length, i0, x) {
var i0_ = Math.floor(i0 / 2); var len = length >> 1;
var i1_ = Math.floor((i0 + length) / 2); var offset = offset | 0;
var offset_ = offset - (i0 % 1);
var alpha = -1.586134342059924; var alpha = -1.586134342059924;
var beta = -0.052980118572961; var beta = -0.052980118572961;
@ -1788,39 +1789,31 @@ var JpxImage = (function JpxImageClosure() {
var K = 1.230174104914001; var K = 1.230174104914001;
var K_ = 1 / K; var K_ = 1 / K;
// step 1 // step 1 is combined with step 3
var j = offset_ - 2;
for (var n = i0_ - 1, nn = i1_ + 2; n < nn; n++, j += 2) {
x[j] = K * y[j];
}
// step 2 // step 2
var j = offset_ - 3; for (var j = offset - 3, n = len + 4; n--; j += 2) {
for (var n = i0_ - 2, nn = i1_ + 2; n < nn; n++, j += 2) {
x[j] = K_ * y[j]; x[j] = K_ * y[j];
} }
// step 3 // step 1 & 3
var j = offset_ - 2; for (var j = offset - 2, n = len + 3; n--; j += 2) {
for (var n = i0_ - 1, nn = i1_ + 2; n < nn; n++, j += 2) { x[j] = K * y[j] -
x[j] -= delta * (x[j - 1] + x[j + 1]); delta * (x[j - 1] + x[j + 1]);
} }
// step 4 // step 4
var j = offset_ - 1; for (var j = offset - 1, n = len + 2; n--; j += 2) {
for (var n = i0_ - 1, nn = i1_ + 1; n < nn; n++, j += 2) {
x[j] -= gamma * (x[j - 1] + x[j + 1]); x[j] -= gamma * (x[j - 1] + x[j + 1]);
} }
// step 5 // step 5
var j = offset_; for (var j = offset, n = len + 1; n--; j += 2) {
for (var n = i0_, nn = i1_ + 1; n < nn; n++, j += 2) {
x[j] -= beta * (x[j - 1] + x[j + 1]); x[j] -= beta * (x[j - 1] + x[j + 1]);
} }
// step 6 // step 6
var j = offset_ + 1; for (var j = offset + 1, n = len; n--; j += 2) {
for (var n = i0_, nn = i1_; n < nn; n++, j += 2) {
x[j] -= alpha * (x[j - 1] + x[j + 1]); x[j] -= alpha * (x[j - 1] + x[j + 1]);
} }
}; };
@ -1837,16 +1830,15 @@ var JpxImage = (function JpxImageClosure() {
ReversibleTransform.prototype = Object.create(Transform.prototype); ReversibleTransform.prototype = Object.create(Transform.prototype);
ReversibleTransform.prototype.filter = ReversibleTransform.prototype.filter =
function reversibleTransformFilter(y, offset, length, i0, x) { function reversibleTransformFilter(y, offset, length, i0, x) {
var i0_ = Math.floor(i0 / 2); var len = length >> 1;
var i1_ = Math.floor((i0 + length) / 2); var offset = offset | 0;
var offset_ = offset - (i0 % 1);
for (var n = i0_, nn = i1_ + 1, j = offset_; n < nn; n++, j += 2) { for (var j = offset, n = len + 1; n--; j += 2) {
x[j] = y[j] - Math.floor((y[j - 1] + y[j + 1] + 2) / 4); x[j] = y[j] - ((y[j - 1] + y[j + 1] + 2) >> 2);
} }
for (var n = i0_, nn = i1_, j = offset_ + 1; n < nn; n++, j += 2) { for (var j = offset + 1, n = len; n--; j += 2) {
x[j] = y[j] + Math.floor((x[j - 1] + x[j + 1]) / 2); x[j] = y[j] + ((x[j - 1] + x[j + 1]) >> 1);
} }
}; };