(function() {
'use strict';
/**
* Sepia Filter
* Based on: Pixastic Lib - Sepia filter - v0.1.0
* Copyright (c) 2008 Jacob Seidelin, jseidelin@nihilogic.dk, http://blog.nihilogic.dk/
* @function
* @name Sepia
* @memberof Konva.Filters
* @param {Object} imageData
* @author Jacob Seidelin <jseidelin@nihilogic.dk>
* @license MPL v1.1 [http://www.pixastic.com/lib/license.txt]
* @example
* node.cache();
* node.filters([Konva.Filters.Sepia]);
*/
Konva.Filters.Sepia = function (imageData) {
var data = imageData.data,
w = imageData.width,
y = imageData.height,
w4 = w * 4,
offsetY, x, offset, or, og, ob, r, g, b;
do {
offsetY = (y - 1) * w4;
x = w;
do {
offset = offsetY + (x - 1) * 4;
or = data[offset];
og = data[offset + 1];
ob = data[offset + 2];
r = or * 0.393 + og * 0.769 + ob * 0.189;
g = or * 0.349 + og * 0.686 + ob * 0.168;
b = or * 0.272 + og * 0.534 + ob * 0.131;
data[offset] = r > 255 ? 255 : r;
data[offset + 1] = g > 255 ? 255 : g;
data[offset + 2] = b > 255 ? 255 : b;
data[offset + 3] = data[offset + 3];
} while (--x);
} while (--y);
};
})();