Websites/browserbench.org/JetStream2.0/SeaMonster/gaussian-blur.js - WebKit - Git at Google

 // Taken from: https://github.com/nodeca/glur

 /*
 * The MIT License (MIT)
 *
 * Copyright (c) 2014 Andrei Tupitcyn
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

 // Calculate Gaussian blur of an image using IIR filter
 // The method is taken from Intel's white paper and code example attached to it:
 // https://software.intel.com/en-us/articles/iir-gaussian-blur-filter
 // -implementation-using-intel-advanced-vector-extensions

 var a0, a1, a2, a3, b1, b2, left_corner, right_corner;

 function gaussCoef(sigma) {
   if (sigma < 0.5) {
     sigma = 0.5;
   }

   var a = Math.exp(0.726 * 0.726) / sigma,
       g1 = Math.exp(-a),
       g2 = Math.exp(-2 * a),
       k = (1 - g1) * (1 - g1) / (1 + 2 * a * g1 - g2);

   a0 = k;
   a1 = k * (a - 1) * g1;
   a2 = k * (a + 1) * g1;
   a3 = -k * g2;
   b1 = 2 * g1;
   b2 = -g2;
   left_corner = (a0 + a1) / (1 - b1 - b2);
   right_corner = (a2 + a3) / (1 - b1 - b2);

   // Attempt to force type to FP32.
   return new Float32Array([ a0, a1, a2, a3, b1, b2, left_corner, right_corner ]);
 }

 function convolveRGBA(src, out, line, coeff, width, height) {
   // takes src image and writes the blurred and transposed result into out

   var rgba;
   var prev_src_r, prev_src_g, prev_src_b, prev_src_a;
   var curr_src_r, curr_src_g, curr_src_b, curr_src_a;
   var curr_out_r, curr_out_g, curr_out_b, curr_out_a;
   var prev_out_r, prev_out_g, prev_out_b, prev_out_a;
   var prev_prev_out_r, prev_prev_out_g, prev_prev_out_b, prev_prev_out_a;

   var src_index, out_index, line_index;
   var i, j;
   var coeff_a0, coeff_a1, coeff_b1, coeff_b2;

   for (i = 0; i < height; i++) {
     src_index = i * width;
     out_index = i;
     line_index = 0;

     // left to right
     rgba = src[src_index];

     prev_src_r = rgba & 0xff;
     prev_src_g = (rgba >> 8) & 0xff;
     prev_src_b = (rgba >> 16) & 0xff;
     prev_src_a = (rgba >> 24) & 0xff;

     prev_prev_out_r = prev_src_r * coeff[6];
     prev_prev_out_g = prev_src_g * coeff[6];
     prev_prev_out_b = prev_src_b * coeff[6];
     prev_prev_out_a = prev_src_a * coeff[6];

     prev_out_r = prev_prev_out_r;
     prev_out_g = prev_prev_out_g;
     prev_out_b = prev_prev_out_b;
     prev_out_a = prev_prev_out_a;

     coeff_a0 = coeff[0];
     coeff_a1 = coeff[1];
     coeff_b1 = coeff[4];
     coeff_b2 = coeff[5];

     for (j = 0; j < width; j++) {
       rgba = src[src_index];
       curr_src_r = rgba & 0xff;
       curr_src_g = (rgba >> 8) & 0xff;
       curr_src_b = (rgba >> 16) & 0xff;
       curr_src_a = (rgba >> 24) & 0xff;

       curr_out_r = curr_src_r * coeff_a0 + prev_src_r * coeff_a1 + prev_out_r * coeff_b1 + prev_prev_out_r * coeff_b2;
       curr_out_g = curr_src_g * coeff_a0 + prev_src_g * coeff_a1 + prev_out_g * coeff_b1 + prev_prev_out_g * coeff_b2;
       curr_out_b = curr_src_b * coeff_a0 + prev_src_b * coeff_a1 + prev_out_b * coeff_b1 + prev_prev_out_b * coeff_b2;
       curr_out_a = curr_src_a * coeff_a0 + prev_src_a * coeff_a1 + prev_out_a * coeff_b1 + prev_prev_out_a * coeff_b2;

       prev_prev_out_r = prev_out_r;
       prev_prev_out_g = prev_out_g;
       prev_prev_out_b = prev_out_b;
       prev_prev_out_a = prev_out_a;

       prev_out_r = curr_out_r;
       prev_out_g = curr_out_g;
       prev_out_b = curr_out_b;
       prev_out_a = curr_out_a;

       prev_src_r = curr_src_r;
       prev_src_g = curr_src_g;
       prev_src_b = curr_src_b;
       prev_src_a = curr_src_a;

       line[line_index] = prev_out_r;
       line[line_index + 1] = prev_out_g;
       line[line_index + 2] = prev_out_b;
       line[line_index + 3] = prev_out_a;
       line_index += 4;
       src_index++;
     }

     src_index--;
     line_index -= 4;
     out_index += height * (width - 1);

     // right to left
     rgba = src[src_index];

     prev_src_r = rgba & 0xff;
     prev_src_g = (rgba >> 8) & 0xff;
     prev_src_b = (rgba >> 16) & 0xff;
     prev_src_a = (rgba >> 24) & 0xff;

     prev_prev_out_r = prev_src_r * coeff[7];
     prev_prev_out_g = prev_src_g * coeff[7];
     prev_prev_out_b = prev_src_b * coeff[7];
     prev_prev_out_a = prev_src_a * coeff[7];

     prev_out_r = prev_prev_out_r;
     prev_out_g = prev_prev_out_g;
     prev_out_b = prev_prev_out_b;
     prev_out_a = prev_prev_out_a;

     curr_src_r = prev_src_r;
     curr_src_g = prev_src_g;
     curr_src_b = prev_src_b;
     curr_src_a = prev_src_a;

     coeff_a0 = coeff[2];
     coeff_a1 = coeff[3];

     for (j = width - 1; j >= 0; j--) {
       curr_out_r = curr_src_r * coeff_a0 + prev_src_r * coeff_a1 + prev_out_r * coeff_b1 + prev_prev_out_r * coeff_b2;
       curr_out_g = curr_src_g * coeff_a0 + prev_src_g * coeff_a1 + prev_out_g * coeff_b1 + prev_prev_out_g * coeff_b2;
       curr_out_b = curr_src_b * coeff_a0 + prev_src_b * coeff_a1 + prev_out_b * coeff_b1 + prev_prev_out_b * coeff_b2;
       curr_out_a = curr_src_a * coeff_a0 + prev_src_a * coeff_a1 + prev_out_a * coeff_b1 + prev_prev_out_a * coeff_b2;

       prev_prev_out_r = prev_out_r;
       prev_prev_out_g = prev_out_g;
       prev_prev_out_b = prev_out_b;
       prev_prev_out_a = prev_out_a;

       prev_out_r = curr_out_r;
       prev_out_g = curr_out_g;
       prev_out_b = curr_out_b;
       prev_out_a = curr_out_a;

       prev_src_r = curr_src_r;
       prev_src_g = curr_src_g;
       prev_src_b = curr_src_b;
       prev_src_a = curr_src_a;

       rgba = src[src_index];
       curr_src_r = rgba & 0xff;
       curr_src_g = (rgba >> 8) & 0xff;
       curr_src_b = (rgba >> 16) & 0xff;
       curr_src_a = (rgba >> 24) & 0xff;

       rgba = ((line[line_index] + prev_out_r) << 0) +
         ((line[line_index + 1] + prev_out_g) << 8) +
         ((line[line_index + 2] + prev_out_b) << 16) +
         ((line[line_index + 3] + prev_out_a) << 24);

       out[out_index] = rgba;

       src_index--;
       line_index -= 4;
       out_index -= height;
     }
   }
 }


 function blurRGBA(src, width, height, radius) {
   // Quick exit on zero radius
   if (!radius) { return; }

   // Unify input data type, to keep convolver calls isomorphic
   var src32 = new Uint32Array(src.buffer);

   var out      = new Uint32Array(src32.length),
       tmp_line = new Float32Array(Math.max(width, height) * 4);

   var coeff = gaussCoef(radius);

   convolveRGBA(src32, out, tmp_line, coeff, width, height, radius);
   convolveRGBA(out, src32, tmp_line, coeff, height, width, radius);
 }

 class Benchmark {
     constructor() {
         this.width = 800;
         this.height = 450;
         this.radius = 15;

         const rand = (function() {
             let seed = 49734321;
             return function() {
                 // Robert Jenkins' 32 bit integer hash function.
                 seed = ((seed + 0x7ed55d16) + (seed << 12))  & 0xffffffff;
                 seed = ((seed ^ 0xc761c23c) ^ (seed >>> 19)) & 0xffffffff;
                 seed = ((seed + 0x165667b1) + (seed << 5))   & 0xffffffff;
                 seed = ((seed + 0xd3a2646c) ^ (seed << 9))   & 0xffffffff;
                 seed = ((seed + 0xfd7046c5) + (seed << 3))   & 0xffffffff;
                 seed = ((seed ^ 0xb55a4f09) ^ (seed >>> 16)) & 0xffffffff;
                 return (seed & 0xfffffff) / 0x10000000;
             };
         })();

         const buffer = new Uint32Array(this.width * this.height);
         for (let i = 0; i < buffer.length; ++i)
             buffer[i] = rand();

         this.buffer = buffer;
     }

     runIteration() {
          blurRGBA(this.buffer, this.width, this.height, this.radius);
     }
 }
	// Taken from: https://github.com/nodeca/glur

	/*
	* The MIT License (MIT)
	*
	* Copyright (c) 2014 Andrei Tupitcyn
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is
	* furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in all
	* copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	* SOFTWARE.
	*/

	// Calculate Gaussian blur of an image using IIR filter
	// The method is taken from Intel's white paper and code example attached to it:
	// https://software.intel.com/en-us/articles/iir-gaussian-blur-filter
	// -implementation-using-intel-advanced-vector-extensions

	var a0, a1, a2, a3, b1, b2, left_corner, right_corner;

	function gaussCoef(sigma) {
	if (sigma < 0.5) {
	sigma = 0.5;
	}

	var a = Math.exp(0.726 * 0.726) / sigma,
	g1 = Math.exp(-a),
	g2 = Math.exp(-2 * a),
	k = (1 - g1) * (1 - g1) / (1 + 2 * a * g1 - g2);

	a0 = k;
	a1 = k * (a - 1) * g1;
	a2 = k * (a + 1) * g1;
	a3 = -k * g2;
	b1 = 2 * g1;
	b2 = -g2;
	left_corner = (a0 + a1) / (1 - b1 - b2);
	right_corner = (a2 + a3) / (1 - b1 - b2);

	// Attempt to force type to FP32.
	return new Float32Array([ a0, a1, a2, a3, b1, b2, left_corner, right_corner ]);
	}

	function convolveRGBA(src, out, line, coeff, width, height) {
	// takes src image and writes the blurred and transposed result into out

	var rgba;
	var prev_src_r, prev_src_g, prev_src_b, prev_src_a;
	var curr_src_r, curr_src_g, curr_src_b, curr_src_a;
	var curr_out_r, curr_out_g, curr_out_b, curr_out_a;
	var prev_out_r, prev_out_g, prev_out_b, prev_out_a;
	var prev_prev_out_r, prev_prev_out_g, prev_prev_out_b, prev_prev_out_a;

	var src_index, out_index, line_index;
	var i, j;
	var coeff_a0, coeff_a1, coeff_b1, coeff_b2;

	for (i = 0; i < height; i++) {
	src_index = i * width;
	out_index = i;
	line_index = 0;

	// left to right
	rgba = src[src_index];

	prev_src_r = rgba & 0xff;
	prev_src_g = (rgba >> 8) & 0xff;
	prev_src_b = (rgba >> 16) & 0xff;
	prev_src_a = (rgba >> 24) & 0xff;

	prev_prev_out_r = prev_src_r * coeff[6];
	prev_prev_out_g = prev_src_g * coeff[6];
	prev_prev_out_b = prev_src_b * coeff[6];
	prev_prev_out_a = prev_src_a * coeff[6];

	prev_out_r = prev_prev_out_r;
	prev_out_g = prev_prev_out_g;
	prev_out_b = prev_prev_out_b;
	prev_out_a = prev_prev_out_a;

	coeff_a0 = coeff[0];
	coeff_a1 = coeff[1];
	coeff_b1 = coeff[4];
	coeff_b2 = coeff[5];

	for (j = 0; j < width; j++) {
	rgba = src[src_index];
	curr_src_r = rgba & 0xff;
	curr_src_g = (rgba >> 8) & 0xff;
	curr_src_b = (rgba >> 16) & 0xff;
	curr_src_a = (rgba >> 24) & 0xff;

	curr_out_r = curr_src_r * coeff_a0 + prev_src_r * coeff_a1 + prev_out_r * coeff_b1 + prev_prev_out_r * coeff_b2;
	curr_out_g = curr_src_g * coeff_a0 + prev_src_g * coeff_a1 + prev_out_g * coeff_b1 + prev_prev_out_g * coeff_b2;
	curr_out_b = curr_src_b * coeff_a0 + prev_src_b * coeff_a1 + prev_out_b * coeff_b1 + prev_prev_out_b * coeff_b2;
	curr_out_a = curr_src_a * coeff_a0 + prev_src_a * coeff_a1 + prev_out_a * coeff_b1 + prev_prev_out_a * coeff_b2;

	prev_prev_out_r = prev_out_r;
	prev_prev_out_g = prev_out_g;
	prev_prev_out_b = prev_out_b;
	prev_prev_out_a = prev_out_a;

	prev_out_r = curr_out_r;
	prev_out_g = curr_out_g;
	prev_out_b = curr_out_b;
	prev_out_a = curr_out_a;

	prev_src_r = curr_src_r;
	prev_src_g = curr_src_g;
	prev_src_b = curr_src_b;
	prev_src_a = curr_src_a;

	line[line_index] = prev_out_r;
	line[line_index + 1] = prev_out_g;
	line[line_index + 2] = prev_out_b;
	line[line_index + 3] = prev_out_a;
	line_index += 4;
	src_index++;
	}

	src_index--;
	line_index -= 4;
	out_index += height * (width - 1);

	// right to left
	rgba = src[src_index];

	prev_src_r = rgba & 0xff;
	prev_src_g = (rgba >> 8) & 0xff;
	prev_src_b = (rgba >> 16) & 0xff;
	prev_src_a = (rgba >> 24) & 0xff;

	prev_prev_out_r = prev_src_r * coeff[7];
	prev_prev_out_g = prev_src_g * coeff[7];
	prev_prev_out_b = prev_src_b * coeff[7];
	prev_prev_out_a = prev_src_a * coeff[7];

	prev_out_r = prev_prev_out_r;
	prev_out_g = prev_prev_out_g;
	prev_out_b = prev_prev_out_b;
	prev_out_a = prev_prev_out_a;

	curr_src_r = prev_src_r;
	curr_src_g = prev_src_g;
	curr_src_b = prev_src_b;
	curr_src_a = prev_src_a;

	coeff_a0 = coeff[2];
	coeff_a1 = coeff[3];

	for (j = width - 1; j >= 0; j--) {
	curr_out_r = curr_src_r * coeff_a0 + prev_src_r * coeff_a1 + prev_out_r * coeff_b1 + prev_prev_out_r * coeff_b2;
	curr_out_g = curr_src_g * coeff_a0 + prev_src_g * coeff_a1 + prev_out_g * coeff_b1 + prev_prev_out_g * coeff_b2;
	curr_out_b = curr_src_b * coeff_a0 + prev_src_b * coeff_a1 + prev_out_b * coeff_b1 + prev_prev_out_b * coeff_b2;
	curr_out_a = curr_src_a * coeff_a0 + prev_src_a * coeff_a1 + prev_out_a * coeff_b1 + prev_prev_out_a * coeff_b2;

	prev_prev_out_r = prev_out_r;
	prev_prev_out_g = prev_out_g;
	prev_prev_out_b = prev_out_b;
	prev_prev_out_a = prev_out_a;

	prev_out_r = curr_out_r;
	prev_out_g = curr_out_g;
	prev_out_b = curr_out_b;
	prev_out_a = curr_out_a;

	prev_src_r = curr_src_r;
	prev_src_g = curr_src_g;
	prev_src_b = curr_src_b;
	prev_src_a = curr_src_a;

	rgba = src[src_index];
	curr_src_r = rgba & 0xff;
	curr_src_g = (rgba >> 8) & 0xff;
	curr_src_b = (rgba >> 16) & 0xff;
	curr_src_a = (rgba >> 24) & 0xff;

	rgba = ((line[line_index] + prev_out_r) << 0) +
	((line[line_index + 1] + prev_out_g) << 8) +
	((line[line_index + 2] + prev_out_b) << 16) +
	((line[line_index + 3] + prev_out_a) << 24);

	out[out_index] = rgba;

	src_index--;
	line_index -= 4;
	out_index -= height;
	}
	}
	}


	function blurRGBA(src, width, height, radius) {
	// Quick exit on zero radius
	if (!radius) { return; }

	// Unify input data type, to keep convolver calls isomorphic
	var src32 = new Uint32Array(src.buffer);

	var out = new Uint32Array(src32.length),
	tmp_line = new Float32Array(Math.max(width, height) * 4);

	var coeff = gaussCoef(radius);

	convolveRGBA(src32, out, tmp_line, coeff, width, height, radius);
	convolveRGBA(out, src32, tmp_line, coeff, height, width, radius);
	}

	class Benchmark {
	constructor() {
	this.width = 800;
	this.height = 450;
	this.radius = 15;

	const rand = (function() {
	let seed = 49734321;
	return function() {
	// Robert Jenkins' 32 bit integer hash function.
	seed = ((seed + 0x7ed55d16) + (seed << 12)) & 0xffffffff;
	seed = ((seed ^ 0xc761c23c) ^ (seed >>> 19)) & 0xffffffff;
	seed = ((seed + 0x165667b1) + (seed << 5)) & 0xffffffff;
	seed = ((seed + 0xd3a2646c) ^ (seed << 9)) & 0xffffffff;
	seed = ((seed + 0xfd7046c5) + (seed << 3)) & 0xffffffff;
	seed = ((seed ^ 0xb55a4f09) ^ (seed >>> 16)) & 0xffffffff;
	return (seed & 0xfffffff) / 0x10000000;
	};
	})();

	const buffer = new Uint32Array(this.width * this.height);
	for (let i = 0; i < buffer.length; ++i)
	buffer[i] = rand();

	this.buffer = buffer;
	}

	runIteration() {
	blurRGBA(this.buffer, this.width, this.height, this.radius);
	}
	}