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updated Noise filter and test

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Eric Rowell
2014-01-02 22:21:21 -08:00
parent 50a91d1e8b
commit 4074eef3aa
3 changed files with 27 additions and 120 deletions
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73
src/filters/Noise.js
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@@ -4,66 +4,35 @@
* Noise Filter. Randomly adds or substracts to the color channels.
* Performs w*h pixel reads and w*h pixel writes.
* @function
* @author ippo615
* @memberof Kinetic.Filters
* @param {ImageData} src, the source image data (what will be transformed)
* @param {ImageData} dst, the destination image data (where it will be saved)
* @param {Object} opt
* @param {Number} [opt.noiseAmount] The amount of noise to add. Between 0 and 255.
* Each channel of each pixel will change by a random amount
* between +- amount/2. Default is 0.
* @param {Number} [opt.affectAlpha] 1 to add noise to the alpha channel.
* Default is 0.
* @param {Object} imagedata
* @author ippo615
*/
var Noise = function (src, dst, opt) {
var amount = opt.noiseAmount || 0,
affectAlpha = opt.affectAlpha || 0;
var srcPixels = src.data,
dstPixels = dst.data,
nPixels = srcPixels.length,
half = amount / 2,
i;
if (affectAlpha) {
Kinetic.Filters.Noise = function (imageData) {
var amount = this.noise() * 255,
data = imageData.data,
nPixels = data.length,
half = amount / 2,
i;
for (i = 0; i < nPixels; i += 4) {
dstPixels[i + 0] = srcPixels[i + 0] + half - 2 * half * Math.random();
dstPixels[i + 1] = srcPixels[i + 1] + half - 2 * half * Math.random();
dstPixels[i + 2] = srcPixels[i + 2] + half - 2 * half * Math.random();
dstPixels[i + 3] = srcPixels[i + 3] + half - 2 * half * Math.random();
data[i + 0] += half - 2 * half * Math.random();
data[i + 1] += half - 2 * half * Math.random();
data[i + 2] += half - 2 * half * Math.random();
}
} else {
for (i = 0; i < nPixels; i += 4) {
dstPixels[i + 0] = srcPixels[i + 0] + half - 2 * half * Math.random();
dstPixels[i + 1] = srcPixels[i + 1] + half - 2 * half * Math.random();
dstPixels[i + 2] = srcPixels[i + 2] + half - 2 * half * Math.random();
dstPixels[i + 3] = srcPixels[i + 3];
}
}
};
Kinetic.Factory.addFilterGetterSetter(Kinetic.Node, 'noise', 32);
Kinetic.Factory.addFilterGetterSetter(Kinetic.Node, 'noise', 0.2);
Kinetic.Filters.Noise = function(src,dst,opt){
if( this === Kinetic.Filters ){
Noise(src, dst||src, opt );
}else{
Noise.call(this, src, dst||src, opt || {
noiseAmount: this.getNoiseAmount()
});
}
};
/**
* get/set noise amount. Returns the amount of noise. Between 0 and 1.
* @name noise
* @method
* @memberof Kinetic.Node.prototype
* @param {Number} noise
* @returns {Number}
*/
/**
* get noise amount. Returns the amount of noise. Between 0 and 255.
* @name getNoiseAmount
* @method
* @memberof Kinetic.Image.prototype
*/
/**
* set noise amount. Sets the amount of noise. Between 0 and 255.
* @name setNoiseAmount
* @method
* @memberof Kinetic.Image.prototype
*/
})();