stephenseo/blue_noise_generation
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

clang-format --style=google

Browse source
This commit is contained in:
Stephen Seo 2023-03-31 18:47:33 +09:00
parent 62d15771ad
commit ecd65fc42b
9 changed files with 1446 additions and 1480 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

29
src/arg_parse.cpp
View file

@ -12,17 +12,21 @@ Args::Args()
output_filename_("output.png") {} output_filename_("output.png") {}
void Args::DisplayHelp() { void Args::DisplayHelp() {
std::cout std::cout << "[-h | --help] [-b <size> | --blue-noise <size>] [--usecl | "
<< "[-h | --help] [-b <size> | --blue-noise <size>] [--usecl | " "--nousecl]\n"
"--nousecl]\n" " -h | --help\t\t\t\tDisplay this help text\n"
" -h | --help\t\t\t\tDisplay this help text\n" " -b <size> | --blue-noise <size>\tGenerate blue noise "
" -b <size> | --blue-noise <size>\tGenerate blue noise square with " "square with "
"size\n" "size\n"
" --usecl | --nousecl\t\t\tUse/Disable OpenCL (enabled by default)\n" " --usecl | --nousecl\t\t\tUse/Disable OpenCL (enabled by "
" -t <int> | --threads <int>\t\tUse CPU thread count when not using " "default)\n"
"OpenCL\n" " -t <int> | --threads <int>\t\tUse CPU thread count when "
" -o <filelname> | --output <filename>\tOutput filename to use\n" "not using "
" --overwrite\t\t\t\tEnable overwriting of file (default disabled)\n"; "OpenCL\n"
" -o <filelname> | --output <filename>\tOutput filename to "
"use\n"
" --overwrite\t\t\t\tEnable overwriting of file (default "
"disabled)\n";
} }
bool Args::ParseArgs(int argc, char **argv) { bool Args::ParseArgs(int argc, char **argv) {
@ -53,7 +57,8 @@ bool Args::ParseArgs(int argc, char **argv) {
std::strcmp(argv[0], "--threads") == 0)) { std::strcmp(argv[0], "--threads") == 0)) {
threads_ = std::strtoul(argv[1], nullptr, 10); threads_ = std::strtoul(argv[1], nullptr, 10);
if (threads_ == 0) { if (threads_ == 0) {
std::cout << "ERROR: Failed to parse thread count, using 4 by default" std::cout << "ERROR: Failed to parse thread count, using 4 by "
"default"
<< std::endl; << std::endl;
threads_ = 4; threads_ = 4;
} }

20
src/arg_parse.hpp
View file

@ -4,19 +4,19 @@
#include <string> #include <string>
struct Args { struct Args {
Args(); Args();
static void DisplayHelp(); static void DisplayHelp();
/// Returns true if help was printed /// Returns true if help was printed
bool ParseArgs(int argc, char **argv); bool ParseArgs(int argc, char **argv);
bool generate_blue_noise_; bool generate_blue_noise_;
bool use_opencl_; bool use_opencl_;
bool overwrite_file_; bool overwrite_file_;
unsigned int blue_noise_size_; unsigned int blue_noise_size_;
unsigned int threads_; unsigned int threads_;
std::string output_filename_; std::string output_filename_;
}; };
#endif #endif

71
src/blue_noise.cl
View file

@ -1,44 +1,45 @@
int twoToOne(int x, int y, int width, int height) { int twoToOne(int x, int y, int width, int height) {
while(x < 0) { while (x < 0) {
x += width; x += width;
} }
while(y < 0) { while (y < 0) {
y += height; y += height;
} }
x = x % width; x = x % width;
y = y % height; y = y % height;
return x + y * width; return x + y * width;
} }
//float gaussian(float x, float y) { // float gaussian(float x, float y) {
// return exp(-(x*x + y*y) / (1.5F * 1.5F * 2.0F)); // return exp(-(x*x + y*y) / (1.5F * 1.5F * 2.0F));
//} // }
__kernel void do_filter( __kernel void do_filter(__global float *filter_out,
__global float *filter_out, __global const float *precomputed, __global const float *precomputed,
__global const int *pbp, const int width, const int height, __global const int *pbp, const int width,
const int filter_size) { const int height, const int filter_size) {
int i = get_global_id(0); int i = get_global_id(0);
if(i < 0 || i >= width * height) { if (i < 0 || i >= width * height) {
return; return;
}
int x = i % width;
int y = i / width;
float sum = 0.0F;
for (int q = 0; q < filter_size; ++q) {
int q_prime = height - filter_size / 2 + y + q;
for (int p = 0; p < filter_size; ++p) {
int p_prime = width - filter_size / 2 + x + p;
if (pbp[twoToOne(p_prime, q_prime, width, height)] != 0) {
sum += precomputed[twoToOne(p, q, filter_size, filter_size)];
// sum += gaussian(p - filter_size / 2.0F + 0.5F, q -
// filter_size / 2.0F + 0.5F);
}
} }
}
int x = i % width; filter_out[i] = sum;
int y = i / width;
float sum = 0.0F;
for(int q = 0; q < filter_size; ++q) {
int q_prime = height - filter_size / 2 + y + q;
for(int p = 0; p < filter_size; ++p) {
int p_prime = width - filter_size / 2 + x + p;
if(pbp[twoToOne(p_prime, q_prime, width, height)] != 0) {
sum += precomputed[twoToOne(p, q, filter_size, filter_size)];
//sum += gaussian(p - filter_size / 2.0F + 0.5F, q - filter_size / 2.0F + 0.5F);
}
}
}
filter_out[i] = sum;
} }
// vim: syntax=c // vim: syntax=c

1352
src/blue_noise.cpp
View file

File diff suppressed because it is too large Load diff

833
src/blue_noise.hpp
View file

@ -1,470 +1,469 @@
#ifndef BLUE_NOISE_HPP #ifndef BLUE_NOISE_HPP
#define BLUE_NOISE_HPP #define BLUE_NOISE_HPP
#include <limits> #include <CL/opencl.h>
#include <vector>
#include <functional>
#include <unordered_set>
#include <condition_variable>
#include <mutex>
#include <thread>
#include <chrono>
#include <cstdio>
#include <queue>
#include <random>
#include <cassert>
#include <stdexcept>
#include <iostream>
#include <cmath>
#include <sys/sysinfo.h> #include <sys/sysinfo.h>
#include <CL/opencl.h> #include <cassert>
#include <chrono>
#include <cmath>
#include <condition_variable>
#include <cstdio>
#include <functional>
#include <iostream>
#include <limits>
#include <mutex>
#include <queue>
#include <random>
#include <stdexcept>
#include <thread>
#include <unordered_set>
#include <vector>
#include "utility.hpp"
#include "image.hpp" #include "image.hpp"
#include "utility.hpp"
namespace dither { namespace dither {
image::Bl blue_noise(int width, int height, int threads = 1, bool use_opencl = true); image::Bl blue_noise(int width, int height, int threads = 1,
bool use_opencl = true);
namespace internal { namespace internal {
std::vector<unsigned int> blue_noise_impl(int width, int height, int threads = 1); std::vector<unsigned int> blue_noise_impl(int width, int height,
std::vector<unsigned int> blue_noise_cl_impl( int threads = 1);
const int width, const int height, const int filter_size, std::vector<unsigned int> blue_noise_cl_impl(const int width, const int height,
cl_context context, cl_device_id device, cl_program program); const int filter_size,
cl_context context,
cl_device_id device,
cl_program program);
inline std::vector<bool> random_noise(int size, int subsize) { inline std::vector<bool> random_noise(int size, int subsize) {
std::vector<bool> pbp(size); std::vector<bool> pbp(size);
std::default_random_engine re(std::random_device{}()); std::default_random_engine re(std::random_device{}());
std::uniform_int_distribution<int> dist(0, size - 1); std::uniform_int_distribution<int> dist(0, size - 1);
// initialize pbp // initialize pbp
for(int i = 0; i < size; ++i) { for (int i = 0; i < size; ++i) {
if(i < subsize) { if (i < subsize) {
pbp[i] = true; pbp[i] = true;
} else { } else {
pbp[i] = false; pbp[i] = false;
}
}
// randomize pbp
for(int i = 0; i < size-1; ++i) {
decltype(dist)::param_type range{i+1, size-1};
int ridx = dist(re, range);
// probably can't use std::swap since using std::vector<bool>
bool temp = pbp[i];
pbp[i] = pbp[ridx];
pbp[ridx] = temp;
}
return pbp;
} }
}
// randomize pbp
for (int i = 0; i < size - 1; ++i) {
decltype(dist)::param_type range{i + 1, size - 1};
int ridx = dist(re, range);
// probably can't use std::swap since using std::vector<bool>
bool temp = pbp[i];
pbp[i] = pbp[ridx];
pbp[ridx] = temp;
}
constexpr float mu = 1.5F; return pbp;
constexpr float mu_squared = mu * mu; }
constexpr float double_mu_squared = 2.0F * mu * mu;
inline float gaussian(float x, float y) { constexpr float mu = 1.5F;
return std::exp(-(x*x + y*y)/(double_mu_squared)); constexpr float mu_squared = mu * mu;
constexpr float double_mu_squared = 2.0F * mu * mu;
inline float gaussian(float x, float y) {
return std::exp(-(x * x + y * y) / (double_mu_squared));
}
inline std::vector<float> precompute_gaussian(int size) {
std::vector<float> precomputed;
if (size % 2 == 0) {
++size;
}
precomputed.reserve(size * size);
for (int i = 0; i < size * size; ++i) {
auto xy = utility::oneToTwo(i, size);
precomputed.push_back(
gaussian(xy.first - (size / 2), xy.second - (size / 2)));
}
return precomputed;
}
inline float filter(const std::vector<bool> &pbp, int x, int y, int width,
int height, int filter_size) {
float sum = 0.0f;
if (filter_size % 2 == 0) {
++filter_size;
}
// Should be range -M/2 to M/2, but size_t cannot be negative, so range
// is 0 to M.
// p' = (M + x - (p - M/2)) % M = (3M/2 + x - p) % M
// q' = (N + y - (q - M/2)) % N = (N + M/2 + y - q) % N
for (int q = 0; q < filter_size; ++q) {
int q_prime = (height - filter_size / 2 + y + q) % height;
for (int p = 0; p < filter_size; ++p) {
int p_prime = (width - filter_size / 2 + x + p) % width;
if (pbp[utility::twoToOne(p_prime, q_prime, width, height)]) {
sum += gaussian(p - filter_size / 2, q - filter_size / 2);
}
} }
}
inline std::vector<float> precompute_gaussian(int size) { return sum;
std::vector<float> precomputed; }
if (size % 2 == 0) {
++size;
}
precomputed.reserve(size * size);
for(int i = 0; i < size * size; ++i) { inline float filter_with_precomputed(const std::vector<bool> &pbp, int x, int y,
auto xy = utility::oneToTwo(i, size); int width, int height, int filter_size,
precomputed.push_back(gaussian( const std::vector<float> &precomputed) {
xy.first - (size / 2), float sum = 0.0f;
xy.second - (size / 2)));
}
return precomputed; if (filter_size % 2 == 0) {
++filter_size;
}
for (int q = 0; q < filter_size; ++q) {
int q_prime = (height - filter_size / 2 + y + q) % height;
for (int p = 0; p < filter_size; ++p) {
int p_prime = (width - filter_size / 2 + x + p) % width;
if (pbp[utility::twoToOne(p_prime, q_prime, width, height)]) {
sum += precomputed[utility::twoToOne(p, q, filter_size, filter_size)];
}
} }
}
inline float filter( return sum;
const std::vector<bool>& pbp, }
int x, int y,
int width, int height, int filter_size) {
float sum = 0.0f;
if (filter_size % 2 == 0) { inline void compute_filter(const std::vector<bool> &pbp, int width, int height,
++filter_size; int count, int filter_size,
std::vector<float> &filter_out,
const std::vector<float> *precomputed = nullptr,
int threads = 1) {
if (threads == 1) {
if (precomputed) {
for (int y = 0; y < height; ++y) {
for (int x = 0; x < width; ++x) {
filter_out[utility::twoToOne(x, y, width, height)] =
internal::filter_with_precomputed(pbp, x, y, width, height,
filter_size, *precomputed);
} }
}
// Should be range -M/2 to M/2, but size_t cannot be negative, so range } else {
// is 0 to M. for (int y = 0; y < height; ++y) {
// p' = (M + x - (p - M/2)) % M = (3M/2 + x - p) % M for (int x = 0; x < width; ++x) {
// q' = (N + y - (q - M/2)) % N = (N + M/2 + y - q) % N filter_out[utility::twoToOne(x, y, width, height)] =
for(int q = 0; q < filter_size; ++q) { internal::filter(pbp, x, y, width, height, filter_size);
int q_prime = (height - filter_size / 2 + y + q) % height;
for(int p = 0; p < filter_size; ++p) {
int p_prime = (width - filter_size / 2 + x + p) % width;
if(pbp[utility::twoToOne(p_prime, q_prime, width, height)]) {
sum += gaussian(p - filter_size/2,
q - filter_size/2);
}
}
} }
}
return sum;
} }
} else {
inline float filter_with_precomputed( if (threads == 0) {
const std::vector<bool>& pbp, threads = 10;
int x, int y,
int width, int height, int filter_size,
const std::vector<float> &precomputed) {
float sum = 0.0f;
if (filter_size % 2 == 0) {
++filter_size;
}
for(int q = 0; q < filter_size; ++q) {
int q_prime = (height - filter_size / 2 + y + q) % height;
for(int p = 0; p < filter_size; ++p) {
int p_prime = (width - filter_size / 2 + x + p) % width;
if(pbp[utility::twoToOne(p_prime, q_prime, width, height)]) {
sum += precomputed[utility::twoToOne(p, q, filter_size, filter_size)];
}
}
}
return sum;
} }
int active_count = 0;
inline void compute_filter( std::mutex cv_mutex;
const std::vector<bool> &pbp, int width, int height, std::condition_variable cv;
int count, int filter_size, std::vector<float> &filter_out, if (precomputed) {
const std::vector<float> *precomputed = nullptr, for (int i = 0; i < count; ++i) {
int threads = 1) { {
if(threads == 1) { std::unique_lock lock(cv_mutex);
if(precomputed) { active_count += 1;
for(int y = 0; y < height; ++y) {
for(int x = 0; x < width; ++x) {
filter_out[utility::twoToOne(x, y, width, height)] =
internal::filter_with_precomputed(
pbp, x, y, width, height, filter_size, *precomputed);
}
}
} else {
for(int y = 0; y < height; ++y) {
for(int x = 0; x < width; ++x) {
filter_out[utility::twoToOne(x, y, width, height)] =
internal::filter(pbp, x, y, width, height, filter_size);
}
}
}
} else {
if(threads == 0) {
threads = 10;
}
int active_count = 0;
std::mutex cv_mutex;
std::condition_variable cv;
if(precomputed) {
for(int i = 0; i < count; ++i) {
{
std::unique_lock lock(cv_mutex);
active_count += 1;
}
std::thread t([] (int *ac, std::mutex *cvm,
std::condition_variable *cv, int i,
const std::vector<bool> *pbp, int width,
int height, int filter_size,
std::vector<float> *fout,
const std::vector<float> *precomputed) {
int x, y;
std::tie(x, y) = utility::oneToTwo(i, width);
(*fout)[i] = internal::filter_with_precomputed(
*pbp, x, y, width, height, filter_size, *precomputed);
std::unique_lock lock(*cvm);
*ac -= 1;
cv->notify_all();
},
&active_count, &cv_mutex, &cv, i, &pbp, width, height,
filter_size, &filter_out, precomputed);
t.detach();
std::unique_lock lock(cv_mutex);
while(active_count >= threads) {
cv.wait_for(lock, std::chrono::seconds(1));
}
}
} else {
for(int i = 0; i < count; ++i) {
{
std::unique_lock lock(cv_mutex);
active_count += 1;
}
std::thread t([] (int *ac, std::mutex *cvm,
std::condition_variable *cv, int i,
const std::vector<bool> *pbp, int width,
int height, int filter_size,
std::vector<float> *fout) {
int x, y;
std::tie(x, y) = utility::oneToTwo(i, width);
(*fout)[i] = internal::filter(
*pbp, x, y, width, height, filter_size);
std::unique_lock lock(*cvm);
*ac -= 1;
cv->notify_all();
},
&active_count, &cv_mutex, &cv, i, &pbp, width, height,
filter_size, &filter_out);
t.detach();
std::unique_lock lock(cv_mutex);
while(active_count >= threads) {
cv.wait_for(lock, std::chrono::seconds(1));
}
}
}
std::unique_lock lock(cv_mutex);
while(active_count > 0) {
cv.wait_for(lock, std::chrono::seconds(1));
}
} }
std::thread t(
[](int *ac, std::mutex *cvm, std::condition_variable *cv, int i,
const std::vector<bool> *pbp, int width, int height,
int filter_size, std::vector<float> *fout,
const std::vector<float> *precomputed) {
int x, y;
std::tie(x, y) = utility::oneToTwo(i, width);
(*fout)[i] = internal::filter_with_precomputed(
*pbp, x, y, width, height, filter_size, *precomputed);
std::unique_lock lock(*cvm);
*ac -= 1;
cv->notify_all();
},
&active_count, &cv_mutex, &cv, i, &pbp, width, height, filter_size,
&filter_out, precomputed);
t.detach();
std::unique_lock lock(cv_mutex);
while (active_count >= threads) {
cv.wait_for(lock, std::chrono::seconds(1));
}
}
} else {
for (int i = 0; i < count; ++i) {
{
std::unique_lock lock(cv_mutex);
active_count += 1;
}
std::thread t(
[](int *ac, std::mutex *cvm, std::condition_variable *cv, int i,
const std::vector<bool> *pbp, int width, int height,
int filter_size, std::vector<float> *fout) {
int x, y;
std::tie(x, y) = utility::oneToTwo(i, width);
(*fout)[i] =
internal::filter(*pbp, x, y, width, height, filter_size);
std::unique_lock lock(*cvm);
*ac -= 1;
cv->notify_all();
},
&active_count, &cv_mutex, &cv, i, &pbp, width, height, filter_size,
&filter_out);
t.detach();
std::unique_lock lock(cv_mutex);
while (active_count >= threads) {
cv.wait_for(lock, std::chrono::seconds(1));
}
}
} }
std::unique_lock lock(cv_mutex);
inline std::pair<int, int> filter_minmax(const std::vector<float> &filter, while (active_count > 0) {
std::vector<bool> pbp) { cv.wait_for(lock, std::chrono::seconds(1));
// ensure minority pixel is "true"
unsigned int count = 0;
for (bool value : pbp) {
if(value) {
++count;
}
}
if (count * 2 >= pbp.size()) {
//std::cout << "MINMAX flip\n"; // DEBUG
for (unsigned int i = 0; i < pbp.size(); ++i) {
pbp[i] = !pbp[i];
}
}
float min = std::numeric_limits<float>::infinity();
float max = -std::numeric_limits<float>::infinity();
int min_index = -1;
int max_index = -1;
for(std::vector<float>::size_type i = 0; i < filter.size(); ++i) {
if(!pbp[i] && filter[i] < min) {
min_index = i;
min = filter[i];
}
if(pbp[i] && filter[i] > max) {
max_index = i;
max = filter[i];
}
}
return {min_index, max_index};
} }
}
}
inline std::pair<int, int> filter_abs_minmax( inline std::pair<int, int> filter_minmax(const std::vector<float> &filter,
const std::vector<float> &filter) { std::vector<bool> pbp) {
float min = std::numeric_limits<float>::infinity(); // ensure minority pixel is "true"
float max = -std::numeric_limits<float>::infinity(); unsigned int count = 0;
int min_index = -1; for (bool value : pbp) {
int max_index = -1; if (value) {
++count;
std::default_random_engine re(std::random_device{}());
std::size_t startIdx = std::uniform_int_distribution<std::size_t>(0, filter.size() - 1)(re);
for(std::vector<float>::size_type i = startIdx; i < filter.size(); ++i) {
if(filter[i] < min) {
min_index = i;
min = filter[i];
}
if(filter[i] > max) {
max_index = i;
max = filter[i];
}
}
for(std::vector<float>::size_type i = 0; i < startIdx; ++i) {
if(filter[i] < min) {
min_index = i;
min = filter[i];
}
if(filter[i] > max) {
max_index = i;
max = filter[i];
}
}
return {min_index, max_index};
} }
}
inline int get_one_or_zero( if (count * 2 >= pbp.size()) {
const std::vector<bool>& pbp, bool get_one, // std::cout << "MINMAX flip\n"; // DEBUG
int idx, int width, int height) { for (unsigned int i = 0; i < pbp.size(); ++i) {
std::queue<int> checking_indices; pbp[i] = !pbp[i];
auto xy = utility::oneToTwo(idx, width);
int count = 0;
int loops = 0;
enum { D_DOWN = 0, D_LEFT = 1, D_UP = 2, D_RIGHT = 3 } dir = D_RIGHT;
int next;
while(true) {
if(count == 0) {
switch(dir) {
case D_RIGHT:
xy.first = (xy.first + 1) % width;
++loops;
count = loops * 2 - 1;
dir = D_DOWN;
break;
case D_DOWN:
xy.first = (xy.first + width - 1) % width;
count = loops * 2 - 1;
dir = D_LEFT;
break;
case D_LEFT:
xy.second = (xy.second + height - 1) % height;
count = loops * 2 - 1;
dir = D_UP;
break;
case D_UP:
xy.first = (xy.first + 1) % width;
count = loops * 2 - 1;
dir = D_RIGHT;
break;
}
} else {
switch(dir) {
case D_DOWN:
xy.second = (xy.second + 1) % height;
--count;
break;
case D_LEFT:
xy.first = (xy.first + width - 1) % width;
--count;
break;
case D_UP:
xy.second = (xy.second + height - 1) % height;
--count;
break;
case D_RIGHT:
xy.first = (xy.first + 1) % width;
--count;
break;
}
}
next = utility::twoToOne(xy.first, xy.second, width, height);
if((get_one && pbp[next]) || (!get_one && !pbp[next])) {
return next;
}
}
return idx;
} }
}
inline void write_filter(const std::vector<float> &filter, int width, const char *filename) { float min = std::numeric_limits<float>::infinity();
int min, max; float max = -std::numeric_limits<float>::infinity();
std::tie(min, max) = filter_abs_minmax(filter); int min_index = -1;
int max_index = -1;
printf("Writing to %s, min is %.3f, max is %.3f\n", filename, filter[min], filter[max]); for (std::vector<float>::size_type i = 0; i < filter.size(); ++i) {
FILE *filter_image = fopen(filename, "w"); if (!pbp[i] && filter[i] < min) {
fprintf(filter_image, "P2\n%d %d\n255\n", width, (int)filter.size() / width); min_index = i;
for(std::vector<float>::size_type i = 0; i < filter.size(); ++i) { min = filter[i];
fprintf(filter_image, "%d ",
(int)(((filter[i] - filter[min])
/ (filter[max] - filter[min]))
* 255.0f));
if((i + 1) % width == 0) {
fputc('\n', filter_image);
}
}
fclose(filter_image);
} }
if (pbp[i] && filter[i] > max) {
inline image::Bl toBl(const std::vector<bool>& pbp, int width) { max_index = i;
image::Bl bwImage(width, pbp.size() / width); max = filter[i];
assert((unsigned long)bwImage.getSize() >= pbp.size()
&& "New image::Bl size too small (pbp's size is not a multiple of width)");
for(unsigned int i = 0; i < pbp.size(); ++i) {
bwImage.getData()[i] = pbp[i] ? 255 : 0;
}
return bwImage;
} }
}
inline image::Bl rangeToBl(const std::vector<unsigned int> &values, int width) { return {min_index, max_index};
int min = std::numeric_limits<int>::max(); }
int max = std::numeric_limits<int>::min();
for (int value : values) { inline std::pair<int, int> filter_abs_minmax(const std::vector<float> &filter) {
if (value < min) { float min = std::numeric_limits<float>::infinity();
min = value; float max = -std::numeric_limits<float>::infinity();
} int min_index = -1;
if (value > max) { int max_index = -1;
max = value;
} std::default_random_engine re(std::random_device{}());
} std::size_t startIdx =
std::uniform_int_distribution<std::size_t>(0, filter.size() - 1)(re);
for (std::vector<float>::size_type i = startIdx; i < filter.size(); ++i) {
if (filter[i] < min) {
min_index = i;
min = filter[i];
}
if (filter[i] > max) {
max_index = i;
max = filter[i];
}
}
for (std::vector<float>::size_type i = 0; i < startIdx; ++i) {
if (filter[i] < min) {
min_index = i;
min = filter[i];
}
if (filter[i] > max) {
max_index = i;
max = filter[i];
}
}
return {min_index, max_index};
}
inline int get_one_or_zero(const std::vector<bool> &pbp, bool get_one, int idx,
int width, int height) {
std::queue<int> checking_indices;
auto xy = utility::oneToTwo(idx, width);
int count = 0;
int loops = 0;
enum { D_DOWN = 0, D_LEFT = 1, D_UP = 2, D_RIGHT = 3 } dir = D_RIGHT;
int next;
while (true) {
if (count == 0) {
switch (dir) {
case D_RIGHT:
xy.first = (xy.first + 1) % width;
++loops;
count = loops * 2 - 1;
dir = D_DOWN;
break;
case D_DOWN:
xy.first = (xy.first + width - 1) % width;
count = loops * 2 - 1;
dir = D_LEFT;
break;
case D_LEFT:
xy.second = (xy.second + height - 1) % height;
count = loops * 2 - 1;
dir = D_UP;
break;
case D_UP:
xy.first = (xy.first + 1) % width;
count = loops * 2 - 1;
dir = D_RIGHT;
break;
}
} else {
switch (dir) {
case D_DOWN:
xy.second = (xy.second + 1) % height;
--count;
break;
case D_LEFT:
xy.first = (xy.first + width - 1) % width;
--count;
break;
case D_UP:
xy.second = (xy.second + height - 1) % height;
--count;
break;
case D_RIGHT:
xy.first = (xy.first + 1) % width;
--count;
break;
}
}
next = utility::twoToOne(xy.first, xy.second, width, height);
if ((get_one && pbp[next]) || (!get_one && !pbp[next])) {
return next;
}
}
return idx;
}
inline void write_filter(const std::vector<float> &filter, int width,
const char *filename) {
int min, max;
std::tie(min, max) = filter_abs_minmax(filter);
printf("Writing to %s, min is %.3f, max is %.3f\n", filename, filter[min],
filter[max]);
FILE *filter_image = fopen(filename, "w");
fprintf(filter_image, "P2\n%d %d\n255\n", width, (int)filter.size() / width);
for (std::vector<float>::size_type i = 0; i < filter.size(); ++i) {
fprintf(filter_image, "%d ",
(int)(((filter[i] - filter[min]) / (filter[max] - filter[min])) *
255.0f));
if ((i + 1) % width == 0) {
fputc('\n', filter_image);
}
}
fclose(filter_image);
}
inline image::Bl toBl(const std::vector<bool> &pbp, int width) {
image::Bl bwImage(width, pbp.size() / width);
assert((unsigned long)bwImage.getSize() >= pbp.size() &&
"New image::Bl size too small (pbp's size is not a multiple of "
"width)");
for (unsigned int i = 0; i < pbp.size(); ++i) {
bwImage.getData()[i] = pbp[i] ? 255 : 0;
}
return bwImage;
}
inline image::Bl rangeToBl(const std::vector<unsigned int> &values, int width) {
int min = std::numeric_limits<int>::max();
int max = std::numeric_limits<int>::min();
for (int value : values) {
if (value < min) {
min = value;
}
if (value > max) {
max = value;
}
}
#ifndef NDEBUG #ifndef NDEBUG
std::cout << "rangeToBl: Got min == " << min << " and max == " << max << std::endl; std::cout << "rangeToBl: Got min == " << min << " and max == " << max
<< std::endl;
#endif #endif
max -= min; max -= min;
image::Bl grImage(width, values.size() / width); image::Bl grImage(width, values.size() / width);
assert((unsigned long)grImage.getSize() >= values.size() assert((unsigned long)grImage.getSize() >= values.size() &&
&& "New image::Bl size too small (values' size is not a multiple of width)"); "New image::Bl size too small (values' size is not a multiple of "
"width)");
for(unsigned int i = 0; i < values.size(); ++i) { for (unsigned int i = 0; i < values.size(); ++i) {
grImage.getData()[i] = std::round(((float)((int)(values[i]) - min) / (float)max) * 255.0F); grImage.getData()[i] =
} std::round(((float)((int)(values[i]) - min) / (float)max) * 255.0F);
}
return grImage; return grImage;
}
inline std::pair<int, int> filter_minmax_in_range(
int start, int width, int height, int range,
const std::vector<float> &vec) {
float max = -std::numeric_limits<float>::infinity();
float min = std::numeric_limits<float>::infinity();
int maxIdx = -1;
int minIdx = -1;
auto startXY = utility::oneToTwo(start, width);
for (int y = startXY.second - range / 2; y <= startXY.second + range / 2;
++y) {
for (int x = startXY.first - range / 2; x <= startXY.first + range / 2;
++x) {
int idx = utility::twoToOne(x, y, width, height);
if (idx == start) {
continue;
}
if (vec[idx] < min) {
min = vec[idx];
minIdx = idx;
}
if (vec[idx] > max) {
max = vec[idx];
maxIdx = idx;
}
} }
}
inline std::pair<int, int> filter_minmax_in_range(int start, int width, if (minIdx < 0) {
int height, throw std::runtime_error("Invalid minIdx value");
int range, } else if (maxIdx < 0) {
const std::vector<float> &vec) { throw std::runtime_error("Invalid maxIdx value");
float max = -std::numeric_limits<float>::infinity(); }
float min = std::numeric_limits<float>::infinity(); return {minIdx, maxIdx};
}
} // namespace internal
int maxIdx = -1; } // namespace dither
int minIdx = -1;
auto startXY = utility::oneToTwo(start, width);
for(int y = startXY.second - range / 2; y <= startXY.second + range / 2; ++y) {
for(int x = startXY.first - range / 2; x <= startXY.first + range / 2; ++x) {
int idx = utility::twoToOne(x, y, width, height);
if(idx == start) {
continue;
}
if(vec[idx] < min) {
min = vec[idx];
minIdx = idx;
}
if(vec[idx] > max) {
max = vec[idx];
maxIdx = idx;
}
}
}
if(minIdx < 0) {
throw std::runtime_error("Invalid minIdx value");
} else if(maxIdx < 0) {
throw std::runtime_error("Invalid maxIdx value");
}
return {minIdx, maxIdx};
}
} // namespace dither::internal
} // namespace dither
#endif #endif

348
src/image.cpp
View file

@ -1,241 +1,221 @@
#include "image.hpp" #include "image.hpp"
#include <cstdio>
#include <random>
#include <iostream>
#include <png.h> #include <png.h>
#include <cstdio>
#include <iostream>
#include <random>
bool image::Base::isValid() const { bool image::Base::isValid() const {
return getWidth() > 0 && getHeight() > 0 && getSize() > 0; return getWidth() > 0 && getHeight() > 0 && getSize() > 0;
} }
image::Bl::Bl() : image::Bl::Bl() : data(), width(0), height(0) {}
data(),
width(0),
height(0)
{}
image::Bl::Bl(int width, int height) : image::Bl::Bl(int width, int height)
data(width * height), : data(width * height), width(width), height(height) {}
width(width),
height(height)
{}
image::Bl::Bl(const std::vector<uint8_t> &data, int width) : image::Bl::Bl(const std::vector<uint8_t> &data, int width)
data(data), : data(data), width(width), height(data.size() / width) {}
width(width),
height(data.size() / width)
{}
image::Bl::Bl(std::vector<uint8_t> &&data, int width) : image::Bl::Bl(std::vector<uint8_t> &&data, int width)
data(std::move(data)), : data(std::move(data)), width(width), height(data.size() / width) {}
width(width),
height(data.size() / width)
{}
image::Bl::Bl(const std::vector<float> &data, int width) : image::Bl::Bl(const std::vector<float> &data, int width)
data{}, : data{}, width(width), height(data.size() / width) {
width(width), for (float gspixel : data) {
height(data.size() / width) this->data.push_back(static_cast<uint8_t>(255.0F * gspixel));
{ }
for(float gspixel : data) {
this->data.push_back(static_cast<uint8_t>(255.0F * gspixel));
}
} }
void image::Bl::randomize() { void image::Bl::randomize() {
if(!isValid()) { if (!isValid()) {
return; return;
} }
std::default_random_engine re(std::random_device{}()); std::default_random_engine re(std::random_device{}());
std::uniform_int_distribution<unsigned int> dist; std::uniform_int_distribution<unsigned int> dist;
for(unsigned int i = 0; i < data.size(); ++i) { for (unsigned int i = 0; i < data.size(); ++i) {
data[i] = i < data.size() / 2 ? 255 : 0; data[i] = i < data.size() / 2 ? 255 : 0;
} }
for(unsigned int i = 0; i < data.size() - 1; ++i) { for (unsigned int i = 0; i < data.size() - 1; ++i) {
int ridx = dist(re, decltype(dist)::param_type{i+1, (unsigned int)data.size()-1}); int ridx = dist(
uint8_t temp = data[i]; re, decltype(dist)::param_type{i + 1, (unsigned int)data.size() - 1});
data[i] = data[ridx]; uint8_t temp = data[i];
data[ridx] = temp; data[i] = data[ridx];
} data[ridx] = temp;
}
} }
unsigned int image::Bl::getSize() const { unsigned int image::Bl::getSize() const { return data.size(); }
return data.size();
uint8_t *image::Bl::getData() {
if (!isValid()) {
return nullptr;
}
return &data[0];
} }
uint8_t* image::Bl::getData() { const uint8_t *image::Bl::getDataC() const {
if(!isValid()) { if (!isValid()) {
return nullptr; return nullptr;
} }
return &data[0]; return &data[0];
} }
const uint8_t* image::Bl::getDataC() const { unsigned int image::Bl::getWidth() const { return width; }
if(!isValid()) {
return nullptr;
}
return &data[0];
}
unsigned int image::Bl::getWidth() const { unsigned int image::Bl::getHeight() const { return height; }
return width;
}
unsigned int image::Bl::getHeight() const {
return height;
}
bool image::Bl::canWriteFile(file_type type) { bool image::Bl::canWriteFile(file_type type) {
if(!isValid()) { if (!isValid()) {
std::cout << "Cannot write image because isValid() is false\n"; std::cout << "Cannot write image because isValid() is false\n";
return false; return false;
} }
switch(type) { switch (type) {
case file_type::PBM: case file_type::PBM:
case file_type::PGM: case file_type::PGM:
case file_type::PPM: case file_type::PPM:
case file_type::PNG: case file_type::PNG:
return true; return true;
default: default:
std::cout << "Cannot write image because received invalid file_type\n"; std::cout << "Cannot write image because received invalid "
return false; "file_type\n";
} return false;
}
} }
bool image::Bl::writeToFile(file_type type, bool canOverwrite, const char *filename) { bool image::Bl::writeToFile(file_type type, bool canOverwrite,
if(!isValid() || !canWriteFile(type)) { const char *filename) {
std::cout << "ERROR: Image is not valid or cannot write file type\n"; if (!isValid() || !canWriteFile(type)) {
return false; std::cout << "ERROR: Image is not valid or cannot write file type\n";
return false;
}
FILE *file = fopen(filename, "r");
if (file && !canOverwrite) {
fclose(file);
std::cout << "ERROR: Will not overwite existing file \"" << filename << "\""
<< std::endl;
return false;
}
if (file) {
fclose(file);
}
if (type == file_type::PNG) {
FILE *outfile = fopen(filename, "wb");
if (outfile == nullptr) {
std::cout << "ERROR: Failed to open file for writing (png)\n";
return false;
}
const static auto pngErrorLFn = [](png_structp /* unused */,
png_const_charp message) {
std::cerr << "WARNING [libpng]: " << message << std::endl;
};
const static auto pngWarnLFn = [](png_structp /* unused */,
png_const_charp message) {
std::cerr << "ERROR [libpng]: " << message << std::endl;
};
png_structp png_ptr = png_create_write_struct(
PNG_LIBPNG_VER_STRING, nullptr, pngErrorLFn, pngWarnLFn);
if (png_ptr == nullptr) {
fclose(outfile);
std::cout << "ERROR: Failed to set up writing png file (png_ptr)\n";
return false;
} }
FILE *file = fopen(filename, "r"); png_infop info_ptr = png_create_info_struct(png_ptr);
if(file && !canOverwrite) { if (info_ptr == nullptr) {
fclose(file); png_destroy_write_struct(&png_ptr, nullptr);
std::cout << "ERROR: Will not overwite existing file \"" << filename fclose(outfile);
<< "\"" << std::endl; std::cout << "ERROR: Failed to set up writing png file (png_infop)\n";
return false; return false;
} }
if(file) { if (setjmp(png_jmpbuf(png_ptr))) {
fclose(file); png_destroy_write_struct(&png_ptr, &info_ptr);
fclose(outfile);
std::cout << "ERROR: Failed to write image file (png error)\n";
return false;
} }
if(type == file_type::PNG) { png_init_io(png_ptr, outfile);
FILE *outfile = fopen(filename, "wb");
if (outfile == nullptr) {
std::cout << "ERROR: Failed to open file for writing (png)\n";
return false;
}
const static auto pngErrorLFn = [] (png_structp /* unused */,
png_const_charp message) {
std::cerr << "WARNING [libpng]: " << message << std::endl;
};
const static auto pngWarnLFn = [] (png_structp /* unused */,
png_const_charp message) {
std::cerr << "ERROR [libpng]: " << message << std::endl;
};
png_structp png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, png_set_IHDR(png_ptr, info_ptr, width, height, 8, PNG_COLOR_TYPE_GRAY,
nullptr, PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
pngErrorLFn, PNG_FILTER_TYPE_DEFAULT);
pngWarnLFn);
if (png_ptr == nullptr) { png_write_info(png_ptr, info_ptr);
fclose(outfile);
std::cout << "ERROR: Failed to set up writing png file (png_ptr)\n";
return false;
}
png_infop info_ptr = png_create_info_struct(png_ptr); // png_set_filler(png_ptr, 0, PNG_FILLER_AFTER);
if (info_ptr == nullptr) {
png_destroy_write_struct(&png_ptr, nullptr);
fclose(outfile);
std::cout << "ERROR: Failed to set up writing png file (png_infop)\n";
return false;
}
if (setjmp(png_jmpbuf(png_ptr))) { for (unsigned int j = 0; j < this->data.size() / this->width; ++j) {
png_destroy_write_struct(&png_ptr, &info_ptr); unsigned char *dataPtr = &this->data.at(j * this->width);
fclose(outfile); png_write_rows(png_ptr, &dataPtr, 1);
std::cout << "ERROR: Failed to write image file (png error)\n";
return false;
}
png_init_io(png_ptr, outfile);
png_set_IHDR(png_ptr, info_ptr, width, height, 8, PNG_COLOR_TYPE_GRAY,
PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
PNG_FILTER_TYPE_DEFAULT);
png_write_info(png_ptr, info_ptr);
//png_set_filler(png_ptr, 0, PNG_FILLER_AFTER);
for (unsigned int j = 0; j < this->data.size() / this->width; ++j) {
unsigned char *dataPtr = &this->data.at(j * this->width);
png_write_rows(png_ptr, &dataPtr, 1);
}
png_write_end(png_ptr, nullptr);
png_destroy_write_struct(&png_ptr, &info_ptr);
fclose(outfile);
return true;
} }
switch(type) { png_write_end(png_ptr, nullptr);
png_destroy_write_struct(&png_ptr, &info_ptr);
fclose(outfile);
return true;
}
switch (type) {
case file_type::PBM: case file_type::PBM:
file = fopen(filename, "w"); file = fopen(filename, "w");
fprintf(file, "P1\n%d %d", width, height); fprintf(file, "P1\n%d %d", width, height);
break; break;
case file_type::PGM: case file_type::PGM:
file = fopen(filename, "wb"); file = fopen(filename, "wb");
fprintf(file, "P5\n%d %d\n255\n", width, height); fprintf(file, "P5\n%d %d\n255\n", width, height);
break; break;
case file_type::PPM: case file_type::PPM:
file = fopen(filename, "wb"); file = fopen(filename, "wb");
fprintf(file, "P6\n%d %d\n255\n", width, height); fprintf(file, "P6\n%d %d\n255\n", width, height);
break; break;
default: default:
fclose(file);
std::cout << "ERROR: Cannot write image file, invalid type\n";
return false;
}
for (unsigned int i = 0; i < data.size(); ++i) {
if (type == file_type::PBM && i % width == 0) {
fprintf(file, "\n");
}
switch (type) {
case file_type::PBM:
fprintf(file, "%d ", data[i] == 0 ? 0 : 1);
break;
case file_type::PGM:
// fprintf(file, "%c ", data[i]);
fputc(data[i], file);
break;
case file_type::PPM:
// fprintf(file, "%c %c %c ", data[i], data[i], data[i]);
fputc(data[i], file);
fputc(data[i], file);
fputc(data[i], file);
break;
default:
fclose(file); fclose(file);
std::cout << "ERROR: Cannot write image file, invalid type\n"; std::cout << "ERROR: Cannot write image file, invalid type\n";
return false; return false;
} }
for(unsigned int i = 0; i < data.size(); ++i) { }
if(type == file_type::PBM && i % width == 0) {
fprintf(file, "\n");
}
switch(type) {
case file_type::PBM:
fprintf(file, "%d ", data[i] == 0 ? 0 : 1);
break;
case file_type::PGM:
//fprintf(file, "%c ", data[i]);
fputc(data[i], file);
break;
case file_type::PPM:
//fprintf(file, "%c %c %c ", data[i], data[i], data[i]);
fputc(data[i], file);
fputc(data[i], file);
fputc(data[i], file);
break;
default:
fclose(file);
std::cout << "ERROR: Cannot write image file, invalid type\n";
return false;
}
}
fclose(file); fclose(file);
return true; return true;
} }
bool image::Bl::writeToFile(file_type type, bool canOverwrite, const std::string &filename) { bool image::Bl::writeToFile(file_type type, bool canOverwrite,
return writeToFile(type, canOverwrite, filename.c_str()); const std::string &filename) {
return writeToFile(type, canOverwrite, filename.c_str());
} }

137
src/image.hpp
View file

@ -2,91 +2,96 @@
#define DITHERING_IMAGE_HPP #define DITHERING_IMAGE_HPP
#include <cstdint> #include <cstdint>
#include <vector>
#include <string> #include <string>
#include <vector>
namespace image { namespace image {
enum class color_type { enum class color_type {
Black, Black,
Red, Red,
Green, Green,
Blue, Blue,
Alpha, Alpha,
}; };
enum class file_type { enum class file_type {
PBM, PBM,
PGM, PGM,
PPM, PPM,
PNG, PNG,
}; };
class Base { class Base {
public: public:
Base() = default; Base() = default;
virtual ~Base() {} virtual ~Base() {}
Base(const Base &other) = default; Base(const Base &other) = default;
Base(Base &&other) = default; Base(Base &&other) = default;
Base& operator=(const Base &other) = default; Base &operator=(const Base &other) = default;
Base& operator=(Base &&other) = default; Base &operator=(Base &&other) = default;
virtual void randomize() = 0; virtual void randomize() = 0;
virtual unsigned int getSize() const = 0; virtual unsigned int getSize() const = 0;
virtual uint8_t* getData() = 0; virtual uint8_t *getData() = 0;
virtual const uint8_t* getDataC() const = 0; virtual const uint8_t *getDataC() const = 0;
virtual unsigned int getWidth() const = 0; virtual unsigned int getWidth() const = 0;
virtual unsigned int getHeight() const = 0; virtual unsigned int getHeight() const = 0;
virtual int getTypesCount() = 0; virtual int getTypesCount() = 0;
virtual std::vector<color_type> getTypes() = 0; virtual std::vector<color_type> getTypes() = 0;
virtual int getTypeStride(color_type type) = 0; virtual int getTypeStride(color_type type) = 0;
virtual bool canWriteFile(file_type type) = 0; virtual bool canWriteFile(file_type type) = 0;
virtual bool writeToFile(file_type type, bool canOverwrite, const char *filename) = 0; virtual bool writeToFile(file_type type, bool canOverwrite,
virtual bool writeToFile(file_type type, bool canOverwrite, const std::string &filename) = 0; const char *filename) = 0;
bool isValid() const; virtual bool writeToFile(file_type type, bool canOverwrite,
}; const std::string &filename) = 0;
bool isValid() const;
};
class Bl : public Base { class Bl : public Base {
public: public:
Bl(); Bl();
Bl(int width, int height); Bl(int width, int height);
Bl(const std::vector<uint8_t> &data, int width); Bl(const std::vector<uint8_t> &data, int width);
Bl(std::vector<uint8_t> &&data, int width); Bl(std::vector<uint8_t> &&data, int width);
Bl(const std::vector<float> &data, int width); Bl(const std::vector<float> &data, int width);
virtual ~Bl() {} virtual ~Bl() {}
Bl(const Bl &other) = default; Bl(const Bl &other) = default;
Bl(Bl &&other) = default; Bl(Bl &&other) = default;
Bl& operator=(const Bl &other) = default; Bl &operator=(const Bl &other) = default;
Bl& operator=(Bl &&other) = default; Bl &operator=(Bl &&other) = default;
void randomize() override; void randomize() override;
unsigned int getSize() const override; unsigned int getSize() const override;
uint8_t* getData() override; uint8_t *getData() override;
const uint8_t* getDataC() const override; const uint8_t *getDataC() const override;
unsigned int getWidth() const override; unsigned int getWidth() const override;
unsigned int getHeight() const override; unsigned int getHeight() const override;
int getTypesCount() override { return 1; } int getTypesCount() override { return 1; }
std::vector<color_type> getTypes() override { return { color_type::Black }; } std::vector<color_type> getTypes() override { return {color_type::Black}; }
int getTypeStride(color_type) override { return 0; } int getTypeStride(color_type) override { return 0; }
bool canWriteFile(file_type type) override; bool canWriteFile(file_type type) override;
bool writeToFile(file_type type, bool canOverwrite, const char *filename) override; bool writeToFile(file_type type, bool canOverwrite,
bool writeToFile(file_type type, bool canOverwrite, const std::string &filename) override; const char *filename) override;
private: bool writeToFile(file_type type, bool canOverwrite,
std::vector<uint8_t> data; const std::string &filename) override;
int width;
int height; private:
}; std::vector<uint8_t> data;
} int width;
int height;
};
} // namespace image
#endif #endif

88
src/main.cpp
View file

@ -1,52 +1,52 @@
#include <iostream>
#include <cstdio> #include <cstdio>
#include <iostream>
#include "arg_parse.hpp" #include "arg_parse.hpp"
#include "blue_noise.hpp" #include "blue_noise.hpp"
int main(int argc, char **argv) { int main(int argc, char **argv) {
Args args; Args args;
if(args.ParseArgs(argc, argv)) { if (args.ParseArgs(argc, argv)) {
return 0;
}
// validation
if (args.generate_blue_noise_) {
if (args.output_filename_.empty()) {
std::cout << "ERROR: Cannot generate blue-noise, output filename is not specified"
<< std::endl;
Args::DisplayHelp();
return 1;
} else if (args.blue_noise_size_ < 16) {
std::cout << "ERROR: blue-noise size is too small"
<< std::endl;
Args::DisplayHelp();
return 1;
} else if (!args.overwrite_file_) {
FILE *file = std::fopen(args.output_filename_.c_str(), "r");
if (file) {
std::fclose(file);
std::cout << "ERROR: overwrite not specified, but filename exists"
<< std::endl;
Args::DisplayHelp();
return 1;
}
}
} else {
std::cout << "ERROR: No operation specified\n";
Args::DisplayHelp();
}
if (args.generate_blue_noise_) {
std::cout << "Generating blue_noise..." << std::endl;
image::Bl bl = dither::blue_noise(args.blue_noise_size_,
args.blue_noise_size_,
args.threads_,
args.use_opencl_);
if(!bl.writeToFile(image::file_type::PNG, args.overwrite_file_, args.output_filename_)) {
std::cout << "ERROR: Failed to write blue-noise to file\n";
}
}
return 0; return 0;
}
// validation
if (args.generate_blue_noise_) {
if (args.output_filename_.empty()) {
std::cout << "ERROR: Cannot generate blue-noise, output filename "
"is not specified"
<< std::endl;
Args::DisplayHelp();
return 1;
} else if (args.blue_noise_size_ < 16) {
std::cout << "ERROR: blue-noise size is too small" << std::endl;
Args::DisplayHelp();
return 1;
} else if (!args.overwrite_file_) {
FILE *file = std::fopen(args.output_filename_.c_str(), "r");
if (file) {
std::fclose(file);
std::cout << "ERROR: overwrite not specified, but filename exists"
<< std::endl;
Args::DisplayHelp();
return 1;
}
}
} else {
std::cout << "ERROR: No operation specified\n";
Args::DisplayHelp();
}
if (args.generate_blue_noise_) {
std::cout << "Generating blue_noise..." << std::endl;
image::Bl bl =
dither::blue_noise(args.blue_noise_size_, args.blue_noise_size_,
args.threads_, args.use_opencl_);
if (!bl.writeToFile(image::file_type::PNG, args.overwrite_file_,
args.output_filename_)) {
std::cout << "ERROR: Failed to write blue-noise to file\n";
}
}
return 0;
} }

48
src/utility.hpp
View file

@ -1,33 +1,33 @@
#ifndef DITHERING_UTILITY_HPP #ifndef DITHERING_UTILITY_HPP
#define DITHERING_UTILITY_HPP #define DITHERING_UTILITY_HPP
#include <utility>
#include <cmath> #include <cmath>
#include <utility>
namespace utility { namespace utility {
inline int twoToOne(int x, int y, int width, int height) { inline int twoToOne(int x, int y, int width, int height) {
while(x < 0) { while (x < 0) {
x += width; x += width;
} }
while(y < 0) { while (y < 0) {
y += height; y += height;
} }
x = x % width; x = x % width;
y = y % height; y = y % height;
return x + y * width; return x + y * width;
}
inline std::pair<int, int> oneToTwo(int i, int width) {
return {i % width, i / width};
}
inline float dist(int a, int b, int width) {
auto axy = utility::oneToTwo(a, width);
auto bxy = utility::oneToTwo(b, width);
float dx = axy.first - bxy.first;
float dy = axy.second - bxy.second;
return std::sqrt(dx * dx + dy * dy);
}
} }
inline std::pair<int, int> oneToTwo(int i, int width) {
return {i % width, i / width};
}
inline float dist(int a, int b, int width) {
auto axy = utility::oneToTwo(a, width);
auto bxy = utility::oneToTwo(b, width);
float dx = axy.first - bxy.first;
float dy = axy.second - bxy.second;
return std::sqrt(dx * dx + dy * dy);
}
} // namespace utility
#endif #endif