/*******************************************************

* Copyright (c) 2017, ArrayFire

* All rights reserved.

*

* This file is distributed under 3-clause BSD license.

* The complete license agreement can be obtained at:

* http://arrayfire.com/licenses/BSD-3-Clause

********************************************************/

#include <arrayfire.h>

#include <stdio.h>

#include <af/util.h>

#include <cstdlib>

using namespace af;

static const unsigned ITERS = 64;

array normalize(const array &p_in) {

float mx = max<float>(p_in);

float mn = min<float>(p_in);

return (p_in - mn) / (mx - mn);

}

array sobelFilter(const array &p_in) {

int w = 5;

if (p_in.dims(0) < 512) w = 3;

if (p_in.dims(0) > 2048) w = 7;

int h = 5;

if (p_in.dims(0) < 512) h = 3;

if (p_in.dims(0) > 2048) h = 7;

array ker = gaussianKernel(w, h);

array smooth = convolve(p_in, ker);

for (unsigned i = 1; i < ITERS; ++i) smooth = convolve(smooth, ker);

array Gx, Gy;

sobel(Gx, Gy, smooth, 3);

return normalize(hypot(Gx, Gy));

}

array in, edges, smoothed;

void anisotropicSmoothing() {

smoothed = anisotropicDiffusion(in, 0.125, 0.35f, ITERS);

}

int main(int argc, char *argv[]) {

int device = argc > 1 ? atoi(argv[1]) : 0;

try {

setDevice(device);

info();

printf("** ArrayFire Gradient Anisotropic Smoothing Demo **\n");

Window myWindow("Gradient Anisotropic Smoothing");

in = loadImage(ASSETS_DIR "/examples/images/man.jpg", false);

array sEdges = sobelFilter(in);

anisotropicSmoothing();

array Gx, Gy;

sobel(Gx, Gy, smoothed, 3);

edges = normalize(hypot(Gx, Gy));

while (!myWindow.close()) {

myWindow.grid(2, 2);

myWindow(0, 0).image(in / 255.0f, "Input Image");

myWindow(0, 1).image(normalize(smoothed),

"Anisotropically smooted Input");

myWindow(1, 0).image(normalize(sEdges),

"Gradient Magnitude after gaussian blur t=64");

myWindow(1, 1).image(normalize(edges),

"Gradient Magnitude after diffusion t=64");

myWindow.show();

}

printf(

"\nAnisotropic Diffusion avg runtime for current image in Seconds: "

"%g\n",

timeit(anisotropicSmoothing));

} catch (af::exception &e) {

fprintf(stderr, "%s\n", e.what());

throw;

}

return 0;

}