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Merge branch 'pdpotter-master'

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This commit is contained in:
Kuba Niegowski 2012-11-28 23:28:59 +01:00
commit a6406c85f2
2 changed files with 35 additions and 24 deletions
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55
lib/filter.js
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@ -36,15 +36,28 @@ var Filter = module.exports = function(width, height, Bpp, data, options) {
this._line = 0;
options.filterType = 'filterType' in options ? options.filterType : -1;
this._filters = {
0: this._filterNone.bind(this),
1: this._filterSub.bind(this),
2: this._filterUp.bind(this),
3: this._filterAvg.bind(this),
4: this._filterPaeth.bind(this)
};
options.filterTypes = options.filterTypes || [0,1,2,3,4];
this._filters = {};
for (var filterType in options.filterTypes) {
switch (filterType) {
case '0':
this._filters[filterType] = this._filterNone.bind(this);
break;
case '1':
this._filters[filterType] = this._filterSub.bind(this);
break;
case '2':
this._filters[filterType] = this._filterUp.bind(this);
break;
case '3':
this._filters[filterType] = this._filterAvg.bind(this);
break;
case '4':
this._filters[filterType] = this._filterPaeth.bind(this);
break;
default:
}
}
this.read(this._width * Bpp + 1, this._reverseFilterLine.bind(this));
};
@ -56,7 +69,7 @@ var pixelBppMap = {
0: 0,
1: 0,
2: 0,
3: 0xff,
3: 0xff
},
2: { // LA
0: 0,
@ -85,7 +98,7 @@ Filter.prototype._reverseFilterLine = function(rawData) {
pxRowPos = this._line * pxLineLength,
filter = rawData[0];
if (filter == 0) {
if (filter === 0) {
for (var x = 0; x < this._width; x++) {
var pxPos = pxRowPos + (x << 2),
rawPos = 1 + x * this._Bpp;
@ -177,21 +190,17 @@ Filter.prototype.filter = function() {
for (var y = 0; y < this._height; y++) {
// find best filter for this line (with lowest sum of values)
if (this._options.filterType == -1) {
var min = Infinity,
sel = 0;
var min = Infinity,
sel = 0;
for (var f in this._filters) {
var sum = this._filters[f](pxData, y, null);
if (sum < min) {
sel = f;
min = sum;
}
for (var f in this._filters) {
var sum = this._filters[f](pxData, y, null);
if (sum < min) {
sel = f;
min = sum;
}
} else {
sel = this._options.filterType;
}
this._filters[sel](pxData, y, rawData);
}
return rawData;

4
lib/packer.js
View file

@ -36,6 +36,7 @@ var Packer = module.exports = function(options) {
options.deflateChunkSize = options.deflateChunkSize || 32 * 1024;
options.deflateLevel = options.deflateLevel || 9;
options.deflateStrategy = options.deflateStrategy || 3;
this.readable = true;
};
@ -55,7 +56,8 @@ Packer.prototype.pack = function(data, width, height) {
// compress it
var deflate = zlib.createDeflate({
chunkSize: this._options.deflateChunkSize,
level: this._options.deflateLevel
level: this._options.deflateLevel,
strategy: this._options.deflateStrategy
});
deflate.on('error', this.emit.bind(this, 'error'));