#pragma comment(lib, "Gdiplus.lib")
#include <Windows.h>
#include <GdiPlus.h>

using namespace Gdiplus;


bool GetEncoderClsid(const WCHAR* format, CLSID* pClsid)
{
   UINT num, size;
   Gdiplus::GetImageEncodersSize(&num, &size);
   Gdiplus::ImageCodecInfo* pImageCodecInfo = (Gdiplus::ImageCodecInfo*)(malloc(size));
   Gdiplus::GetImageEncoders(num, size, pImageCodecInfo);
   bool found = false;
   for (UINT ix = 0; !found && ix < num; ++ix) {
     if (0 == _wcsicmp(pImageCodecInfo[ix].MimeType, format) == 0) {
       *pClsid = pImageCodecInfo[ix].Clsid;
       found = true;
     }
   }
   free(pImageCodecInfo);
   return found;
}


struct Pixel
{
	unsigned int a:8;//8bit
	unsigned int r:8;
	unsigned int g:8;
	unsigned int b:8;
};
struct PixelTMP
{
	int a;
	int r;
	int g;
	int b;
};

Pixel Convert(DWORD pxl)
{
	Pixel pixel;
	BYTE *p;
	p=(BYTE*)&pxl;
	pixel.a=p[3];
	pixel.r=p[2];
	pixel.g=p[1];
	pixel.b=p[0];
	return pixel;
}

Pixel RGBtoHSV(Pixel pxl)
{
	PixelTMP pixel;
	pixel.a=255;
	
	int minimum,maximum,delta;
    minimum=min(pxl.r, min(pxl.g, pxl.b));        
    maximum=max(pxl.r, max(pxl.g, pxl.b));      
    delta=maximum-minimum;

    pixel.b=maximum; //r=H, g=S, b=V
    if (pixel.b==0) pixel.g=0;
    else pixel.g=delta*(255/pixel.b);
 
    if (pixel.g==0) pixel.r=0; 
    else
    {  if (maximum==pxl.r)
           pixel.r=60*(pxl.g-pxl.b)/delta;
      else if (maximum==pxl.g)
           pixel.r=120+60*(pxl.b-pxl.r)/delta;
      else if (maximum==pxl.b)
           pixel.r=240+60*(pxl.r-pxl.g)/delta;

      if (pixel.r<0) pixel.r+=360;
      //pixel.r hat noch einen Wertebereich von 0..360 
      //darum jetzt auf 0..255 normieren
      pixel.r=pixel.r*255/360;	
    }
	Pixel rp;
	rp.a=pixel.a;
	rp.r=pixel.r;
	rp.g=pixel.g;
	rp.b=pixel.b;
	return rp;
}

inline DWORD GetPxl(void *Scan0,int Stride,int x,int y)
{
	DWORD *pxl;
	pxl=(DWORD*)(Scan0) + (y * Stride) + (x * 4);
	return *pxl;
}

inline void SetPxl(void *Scan0,int Stride,int x,int y,Pixel np)
{
	DWORD *pxl;
	pxl=(DWORD*)(Scan0) + (y * Stride) + (x * 4);
	DWORD pixel=(((np.a<<24)&0xff000000)|(np.r<<16)|(np.g<<8)|np.b);
	*pxl=pixel;
}


int main()
{
	GdiplusStartupInput gdiplusStartupInput;
    ULONG_PTR gdiplusToken;  
    GdiplusStartup(&gdiplusToken, &gdiplusStartupInput, NULL);
    

	Bitmap bmp(L"D:\\Downloads\\bg.png");

	int w,h;
	w=bmp.GetWidth();
	h=bmp.GetHeight();

	/*Rect rect(0,0,w-1,h-1);
	int flag=ImageLockMode::ImageLockModeUserInputBuf;
	BitmapData *data=new BitmapData();
	UINT *pxls=new UINT[w,h];
	data->Width=w-1;
	data->Height=h-1;
	data->PixelFormat=PixelFormat32bppARGB;
	data->Scan0=pxls;
	data->Stride=4*data->Width;
	bmp.LockBits(&rect,1,PixelFormat32bppARGB,data);*/

	for (/*unsigned */int y=1; y<h-1; y++)
	{
		for(/*unsigned */int x=1; x<w-1; x++)
		{
			Color pxl;
			bmp.GetPixel(x,y,&pxl);//DWORD pixel=GetPxl(data->Scan0,data->Stride,x,y);
			DWORD pixel=pxl.GetValue();//
			Pixel rgb=Convert(pixel);
			Pixel hsv=RGBtoHSV(rgb);
			//ab hier gehts mit der Bildverarbeitung los!
			Color c(hsv.a,hsv.r,hsv.r,hsv.r);//
			bmp.SetPixel(x,y,c);//SetPxl(data->Scan0,data->Stride,x,y,hsv);
			//
		}
	}

	//bmp.UnlockBits(data);
	//delete pxls;

	//DeleteFile("D:\\Downloads\\zbgnew.png");
	CLSID clsid;
	GetEncoderClsid(L"image/png",&clsid);
	bmp.Save(L"D:\\Downloads\\zbgnew.png",&clsid);

	bmp.~bmp();


    GdiplusShutdown(gdiplusToken);
	exit(0);
	return 0;
}