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Fixing inclusion tree when layers are skipped and 0xFF at the packet header end

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notmasteryet 2012-01-14 13:15:16 -06:00
parent ac592a2fdd
commit e43afd3fe5
1 changed files with 59 additions and 39 deletions
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98
src/jpx.js
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@ -81,42 +81,44 @@ var JpxImage = (function JpxImageClosure() {
})();
var InclusionTree = (function InclusionTreeClosure() {
function InclusionTree(width, height) {
function InclusionTree(width, height, defaultValue) {
var levelsLength = log2(Math.max(width, height)) + 1;
this.levels = [];
for (var i = 0; i < levelsLength; i++) {
var items = new Uint8Array(width * height);
for (var j = 0, jj = items.length; j < jj; j++)
items[j] = defaultValue;
var level = {
width: width,
height: height,
items: new Uint8Array(width * height)
items: items
};
this.levels.push(level);
width = Math.ceil(width / 2);
height = Math.ceil(height / 2);
}
this.value = 0;
}
InclusionTree.prototype = {
incrementValue: function inclusionTreeIncrementValue() {
this.value++;
},
reset: function inclusionTreeReset(i, j) {
var currentLevel = 0, currentValue = this.value;
reset: function inclusionTreeReset(i, j, stopValue) {
var currentLevel = 0;
while (currentLevel < this.levels.length) {
var level = this.levels[currentLevel];
var index = i + j * level.width;
level.index = index;
var value = level.items[index];
if (value == currentValue + 1) {
this.currentLevel = currentLevel - 1;
// already know about this one, skiping values
this.skipValue();
return false;
}
if (value != currentValue)
if (value == 0xFF)
break;
level.index = index;
if (value > stopValue) {
this.currentLevel = currentLevel;
// already know about this one, propagating the value to top levels
this.propagateValues();
return false;
}
i >>= 1;
j >>= 1;
currentLevel++;
@ -124,20 +126,33 @@ var JpxImage = (function JpxImageClosure() {
this.currentLevel = currentLevel - 1;
return true;
},
skipValue: function inclusionTreeSetValue() {
incrementValue: function inclusionTreeIncrementValue(stopValue) {
var level = this.levels[this.currentLevel];
level.items[level.index] = stopValue + 1;
this.propagateValues();
},
propagateValues: function inclusionTreePropagateValues() {
var levelIndex = this.currentLevel;
var currentValue = this.value + 1;
while (levelIndex >= 0) {
var level = this.levels[levelIndex];
var currentValue = level.items[level.index];
while (--levelIndex >= 0) {
var level = this.levels[levelIndex];
level.items[level.index] = currentValue;
levelIndex--;
}
},
nextLevel: function inclusionTreeNextLevel() {
var level = this.levels[this.currentLevel];
level.items[level.index] |= 0x80;
this.currentLevel--;
return this.currentLevel >= 0;
var currentLevel = this.currentLevel;
var level = this.levels[currentLevel];
var value = level.items[level.index];
level.items[level.index] = 0xFF;
currentLevel--;
if (currentLevel < 0)
return false;
this.currentLevel = currentLevel;
var level = this.levels[currentLevel];
level.items[level.index] = value;
return true;
}
};
return InclusionTree;
@ -979,15 +994,7 @@ var JpxImage = (function JpxImageClosure() {
var codeblock = codeblocks[i];
var precinctNumber = codeblock.precinctNumber;
}
// building inclusion and zero bit-planes trees
subband.precincts = precincts;
for (var i in precincts) {
var precinct = precincts[i];
var width = precinct.cbxMax - precinct.cbxMin + 1;
var height = precinct.cbyMax - precinct.cbyMin + 1;
precinct.inclusionTree = new InclusionTree(width, height);
precinct.zeroBitPlanesTree = new TagTree(width, height);
}
}
function createPacket(resolution, precinctNumber, layerNumber) {
var precinctCodeblocks = [];
@ -1207,7 +1214,10 @@ var JpxImage = (function JpxImageClosure() {
}
function alignToByte() {
bufferSize = 0;
skipNextBit = false;
if (skipNextBit) {
position++;
skipNextBit = false;
}
}
function readCodingpasses() {
var value = readBits(1);
@ -1248,10 +1258,20 @@ var JpxImage = (function JpxImageClosure() {
} else {
// reading inclusion tree
var precinct = codeblock.precinct;
var inclusionTree = precinct.inclusionTree;
while (inclusionTree.value < layerNumber)
inclusionTree.incrementValue();
if (inclusionTree.reset(codeblockColumn, codeblockRow)) {
var inclusionTree, zeroBitPlanesTree;
if ('inclusionTree' in precinct) {
inclusionTree = precinct.inclusionTree;
} else {
// building inclusion and zero bit-planes trees
var width = precinct.cbxMax - precinct.cbxMin + 1;
var height = precinct.cbyMax - precinct.cbyMin + 1;
inclusionTree = new InclusionTree(width, height, layerNumber);
zeroBitPlanesTree = new TagTree(width, height);
precinct.inclusionTree = inclusionTree;
precinct.zeroBitPlanesTree = zeroBitPlanesTree;
}
if (inclusionTree.reset(codeblockColumn, codeblockRow, layerNumber)) {
while (true) {
if (readBits(1)) {
var valueReady = !inclusionTree.nextLevel();
@ -1261,7 +1281,7 @@ var JpxImage = (function JpxImageClosure() {
break;
}
} else {
inclusionTree.skipValue();
inclusionTree.incrementValue(layerNumber);
break;
}
}
@ -1270,7 +1290,7 @@ var JpxImage = (function JpxImageClosure() {
if (!codeblockIncluded)
continue;
if (firstTimeInclusion) {
var zeroBitPlanesTree = precinct.zeroBitPlanesTree;
zeroBitPlanesTree = precinct.zeroBitPlanesTree;
zeroBitPlanesTree.reset(codeblockColumn, codeblockRow);
while (true) {
if (readBits(1)) {