图像处理-HSV和RGB相互转换

1.实现RGB到HSV的转换函数，函数声明：HSV RGB2HSV(COLORREF c)
函数功能：把COLORREF类对象c的颜色信息转换成一个HSV类对象返回。
代码：

#include
#include
#include
#include
using namespace std;

//RGB->HSV
class HSV //HSV类
{
public:
	double H, S, V;
	HSV() {}
	HSV(double h, double s, double v) :H(h), S(s), V(v) {}
};

HSV RGB2HSV(COLORREF c)//RGB至HSV转换函数
{
	//从COLORREF类对象c中获取颜色RGB值
	BYTE R = GetRValue(c);
	BYTE G = GetGValue(c);
	BYTE B = GetBValue(c);
	double H, S, V;
	//转换公式
	R = R / 255, G = G / 255, B = B / 255;
	V = max(R, G, B);
	if (V != 0) 
	{
		S = (V - min(R, G, B)) / V;
		if (V = R)
		{
			H = (60 * (G - B)) / V - min(R, G, B);
			if (H < 0)
			{
				H = H + 360;
				return HSV(H, S, V);
			}
			return HSV(H, S, V);
		}
		if (V = G)
		{
			H = 120 + ((60 * (B - R)) / (V - min(R, G, B)));
			if (H < 0)
			{
				H = H + 360;
				return HSV(H, S, V);
			}
			return HSV(H, S, V);
		}
		if (V = B)
		{
			H = 240 + ((60 * (R - G)) / (V - min(R, G, B)));
			if (H < 0)
			{
				H = H + 360;
				return HSV(H, S, V);
			}
			return HSV(H, S, V);
		}
	}
	else
	{
		S = 0;
		H = 0;
		return HSV(H, S, V);
	}
}

2、实现HSV到RGB的转换函数，函数声明：COLORREF HSV2RGB(HSV hsv)
函数功能：把HSV类对象hsv的颜色信息转换成一个COLORREF类对象返回。
代码：
 

#include
#include
#include
#include
using namespace std;

//HSV->RGB
COLORREF HSV2RGB(HSV hsv)
{
	//定义变量
	BYTE R, G, B;
	double H, S, V;
	H = hsv.H;
	S = hsv.S;
	V = hsv.V;
	//转换公式
	double C, X, m;
	C = V * S;
	X = C * (1 - (abs(((int)H / 60) % 2 - 1)));
	m = V - C;
	if (H >= 0 && H < 60)
	{
		R = C;
		G = X;
		B = 0;

		R = (R + m) * 255;
		G = (G + m) * 255;
		B = (B + m) * 255;
		//返回COLORREF类型的值
		COLORREF c;
		c = RGB(R, G, B);
		return c;
	}
	if (H >= 60 && H < 120)
	{
		R = X;
		G = C;
		B = 0;

		R = (R + m) * 255;
		G = (G + m) * 255;
		B = (B + m) * 255;
		//返回COLORREF类型的值
		COLORREF c;
		c = RGB(R, G, B);
		return c;
	}
	if (H >= 120 && H < 180)
	{
		R = 0;
		G = C;
		B = X;

		R = (R + m) * 255;
		G = (G + m) * 255;
		B = (B + m) * 255;
		//返回COLORREF类型的值
		COLORREF c;
		c = RGB(R, G, B);
		return c;
	}
	if (H >= 180 && H < 240)
	{
		R = 0;
		G = X;
		B = C;

		R = (R + m) * 255;
		G = (G + m) * 255;
		B = (B + m) * 255;
		//返回COLORREF类型的值
		COLORREF c;
		c = RGB(R, G, B);
		return c;
	}
	if (H >= 240 && H < 300)
	{
		R = X;
		G = 0;
		B = C;

		R = (R + m) * 255;
		G = (G + m) * 255;
		B = (B + m) * 255;
		//返回COLORREF类型的值
		COLORREF c;
		c = RGB(R, G, B);
		return c;
	}
	if (H >= 300 && H < 360)
	{
		R = C;
		G = 0;
		B = X;

		R = (R + m) * 255;
		G = (G + m) * 255;
		B = (B + m) * 255;
		//返回COLORREF类型的值
		COLORREF c;
		c = RGB(R, G, B);
		return c;
	}
}