thedesk/app/node_modules/@jimp/plugin-gaussian/dist/index.js

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2019-09-13 00:38:13 +10:00
"use strict";
require("core-js/modules/es6.object.define-property");
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.default = void 0;
var _utils = require("@jimp/utils");
/**
* Applies a true Gaussian blur to the image (warning: this is VERY slow)
* @param {number} r the pixel radius of the blur
* @param {function(Error, Jimp)} cb (optional) a callback for when complete
* @returns {Jimp} this for chaining of methods
*/
var _default = function _default() {
return {
gaussian: function gaussian(r, cb) {
// http://blog.ivank.net/fastest-gaussian-blur.html
if (typeof r !== 'number') {
return _utils.throwError.call(this, 'r must be a number', cb);
}
if (r < 1) {
return _utils.throwError.call(this, 'r must be greater than 0', cb);
}
var rs = Math.ceil(r * 2.57); // significant radius
var range = rs * 2 + 1;
var rr2 = r * r * 2;
var rr2pi = rr2 * Math.PI;
var weights = [];
for (var y = 0; y < range; y++) {
weights[y] = [];
for (var x = 0; x < range; x++) {
var dsq = Math.pow(x - rs, 2) + Math.pow(y - rs, 2);
weights[y][x] = Math.exp(-dsq / rr2) / rr2pi;
}
}
for (var _y = 0; _y < this.bitmap.height; _y++) {
for (var _x = 0; _x < this.bitmap.width; _x++) {
var red = 0;
var green = 0;
var blue = 0;
var alpha = 0;
var wsum = 0;
for (var iy = 0; iy < range; iy++) {
for (var ix = 0; ix < range; ix++) {
var x1 = Math.min(this.bitmap.width - 1, Math.max(0, ix + _x - rs));
var y1 = Math.min(this.bitmap.height - 1, Math.max(0, iy + _y - rs));
var weight = weights[iy][ix];
var _idx = y1 * this.bitmap.width + x1 << 2;
red += this.bitmap.data[_idx] * weight;
green += this.bitmap.data[_idx + 1] * weight;
blue += this.bitmap.data[_idx + 2] * weight;
alpha += this.bitmap.data[_idx + 3] * weight;
wsum += weight;
}
var idx = _y * this.bitmap.width + _x << 2;
this.bitmap.data[idx] = Math.round(red / wsum);
this.bitmap.data[idx + 1] = Math.round(green / wsum);
this.bitmap.data[idx + 2] = Math.round(blue / wsum);
this.bitmap.data[idx + 3] = Math.round(alpha / wsum);
}
}
}
if ((0, _utils.isNodePattern)(cb)) {
cb.call(this, null, this);
}
return this;
}
};
};
exports.default = _default;
module.exports = exports.default;
//# sourceMappingURL=index.js.map