#include "tbb/tick_count.h"
#include "tbb/blocked_range2d.h"
#include "tbb/parallel_for.h"
#include "tbb/mutex.h"
#include <gdiplus.h>
#include <iostream>
#include <stdlib.h>
#include <cmath>

#pragma comment( lib, "gdiplus.lib" )

static const wchar_t* filename = L"C:\\Users\\Ap0\\Desktop\\poster_rodents_big.jpg";
static const wchar_t* filename_output = L"C:\\Users\\Ap0\\Desktop\\aa2.jpg";
static const wchar_t* filename_output2 = L"C:\\Users\\Ap0\\Desktop\\aa3.jpg";

/*
Go to "Project -> Properties -> Configuration Properties -> Intel Performance Libraries -> Use Intel TBB" set to "Yes"
Go to "Tools -> Options -> Debugging -> Symbols" select checkbox "Microsoft Symbol Servers"
Go to "Project -> Properties -> Configuration Properties -> C/C++ -> Preprocessor -> Preprocessor Definitions" add "_CRT_SECURE_NO_WARNINGS"

https://software.intel.com/en-us/node/506154
https://texus.me/2015/11/17/intel-tbb-parallel-for/
http://registrationcenter-download.intel.com/akdlm/irc_nas/tec/11272/w_tbb_2017.4.187.exe
*/

void rgb_to_grayscale_serial()
{
	Gdiplus::GdiplusStartupInput gdiplusStartupInput;
	ULONG_PTR gdiplusToken;
	Gdiplus::GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);
	Gdiplus::Bitmap myBitmap(filename);
	int x, y;
	BYTE a = 0xFF;
	BYTE r, g, b, avg;
	for (int y = 0; y < myBitmap.GetHeight(); y++){
		for (int x = 0; x < myBitmap.GetWidth(); x++){
			Gdiplus::Color pixelColor;
			myBitmap.GetPixel(x, y, &pixelColor);
			r = pixelColor.GetR();
			g = pixelColor.GetG();
			b = pixelColor.GetB();

			avg = (r + g + b) / 3;
			Gdiplus::Color newColor = Gdiplus::Color::MakeARGB(a, avg, avg, avg);
			myBitmap.SetPixel(x, y, newColor);
		}
	}
	CLSID pngEncoderClsId = { 0x557cf406, 0x1a04, 0x11d3, { 0x9a, 0x73, 0x00, 0x00, 0xf8, 0x1e, 0xf3, 0x2e } };
	myBitmap.Save(filename_output, &pngEncoderClsId, NULL);
	// delete image; image = 0;
	// Gdiplus::GdiplusShutdown(gdiplusToken);
}

class Grayscale
{
private:
	Gdiplus::BitmapData *bitmapData;

public:
	Grayscale(Gdiplus::BitmapData* bitmapData) : bitmapData(bitmapData){}

	void operator()(tbb::blocked_range2d<int> &p) const
	{
		BYTE a = 0xFF;
		BYTE r, g, b, avg;
		byte* line = (byte*)bitmapData->Scan0;

		for (int y = p.rows().begin(); y != p.rows().end(); y++)
		{
			for (int x = p.cols().begin(); x != p.cols().end(); x++)
			{
				byte* pos = line + x * 3;
				Gdiplus::Color pixel = Gdiplus::Color::MakeARGB(a, pos[0], pos[1], pos[2]);

				r = pixel.GetR();
				g = pixel.GetG();
				b = pixel.GetB();
				avg = (r + g + b) / 3;

				pos[0] = avg;
				pos[1] = avg;
				pos[2] = avg;
			}
			line += bitmapData->Stride;
		}
	}
};


void rgb_to_grayscale_parallel()
{
	Gdiplus::GdiplusStartupInput gdiplusStartupInput;
	ULONG_PTR gdiplusToken;
	Gdiplus::GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);
	Gdiplus::Bitmap myBitmap(filename);

	Gdiplus::Rect rect(0, 0, myBitmap.GetWidth(), myBitmap.GetHeight());
	Gdiplus::BitmapData bitmapData;
	myBitmap.LockBits(&rect, Gdiplus::ImageLockModeWrite | Gdiplus::ImageLockModeRead, PixelFormat24bppRGB, &bitmapData);

	tbb::parallel_for(tbb::blocked_range2d<int, int>(0, myBitmap.GetHeight(), 0, myBitmap.GetWidth()), Grayscale(&bitmapData));
	myBitmap.UnlockBits(&bitmapData);

	CLSID pngEncoderClsId = { 0x557cf406, 0x1a04, 0x11d3, { 0x9a, 0x73, 0x00, 0x00, 0xf8, 0x1e, 0xf3, 0x2e } };
	myBitmap.Save(filename_output2, &pngEncoderClsId, NULL);
}
int main()
{
	/* serial converting of RGB image to grayscale */
	printf("Serial converting of RGB image to grayscale...\n");
	getchar();
	tbb::tick_count startTime = tbb::tick_count::now();
	rgb_to_grayscale_serial();
	tbb::tick_count endTime = tbb::tick_count::now();
	printf("Time: %lf seconds\n", (endTime - startTime).seconds());

	/* parallel converting of RGB image to grayscale */
	printf("Parallel converting of RGB image to grayscale...\n");
	getchar();
	startTime = tbb::tick_count::now();
	rgb_to_grayscale_parallel();
	endTime = tbb::tick_count::now();
	printf("Time: %lf seconds\n", (endTime - startTime).seconds());


	getchar();

	return 0;
}