有没有RGB转HSV的优化算法

[LPR_Pro]

将RGB数据转换为HSV,我目前知道的转换方法在运行上效率比较低,有那位知道相关的优化算法,有思路就可以,代码实现更好!
谢谢各位!

[dirdirdir3]

这种经典问题网上查一下就知道了，有的话就有，没有的话问其他人也不会知道.........................

[LPR_Pro]

要是网上能查到我就不需要来开贴了,
希望做过的能提供一些思路.谢谢

[laviewpbt]

给你一个VB网站上对这个优化。

http://www.xbeat.net/vbspeed/c_HSLToRGB.htm

[LPR_Pro]

楼上的,这个是HSLtoRGB的,有没有反向的.

[laviewpbt]

http://www.xbeat.net/vbspeed/c_RGBToHSL.htm

http://www.xbeat.net/vbspeed/c_RGBToHSL2.htm

[LPR_Pro]

这个只是它的转换公式.

[lambochan]

空间换时间,Map住整个RGB来查表...
h = map_HSL[r][g][b].h;// O(1)

其实很多此类的变换/逆变换都可以map住来查表,如alpha合成等,书本不会提及的.

[senr0816]

帮顶~等人解答

[stivenjia]

void	__stdcall	RGB2HSV(COLORREF dwColor,double &dValH,double &dValS,double &dValV)
{
	double var_R = 0.0,var_G = 0.0,var_B = 0.0;
	double del_R = 0.0,del_G = 0.0,del_B = 0.0;
	double var_Min = 0.0,var_Max = 0.0,del_Max = 0.0;

	var_R = ( GetRValue(dwColor) / 255 );                     //RGB from 0 to 255
	var_G = ( GetGValue(dwColor) / 255 );
	var_B = ( GetBValue(dwColor) / 255 );

	var_Min = min( var_R, var_G, var_B );    //Min. value of RGB
	var_Max = max( var_R, var_G, var_B );    //Max. value of RGB
	del_Max = var_Max - var_Min;             //Delta RGB value 

	dValV = var_Max;

	if ( del_Max == 0 )                     //This is a gray, no chroma...
	{
		dValH = 0;                                //HSV results from 0 to 1
		dValS = 0;
	}
	else                                    //Chromatic data...
	{
		dValS = del_Max / var_Max;
		del_R = ( ( ( var_Max - var_R ) / 6 ) + ( del_Max / 2 ) ) / del_Max;
		del_G = ( ( ( var_Max - var_G ) / 6 ) + ( del_Max / 2 ) ) / del_Max;
		del_B = ( ( ( var_Max - var_B ) / 6 ) + ( del_Max / 2 ) ) / del_Max;

		if( var_R == var_Max )	dValH = del_B - del_G;
		else if ( var_G == var_Max ) dValH = ( 1 / 3 ) + del_R - del_B;
		else if ( var_B == var_Max ) dValH = ( 2 / 3 ) + del_G - del_R;

		if ( dValH < 0 ) ; dValH += 1;
		if ( dValH > 1 ) ; dValH -= 1;
	}
}

void	__stdcall	XYZ2LUV(float x, float y, float z, float &L, float &u, float &v)
{
	//定义X0,Y0,X0为D65 CIE 标准光源的色度坐标   
	float X0=95.05f,Y0=100.00f,Z0=108.90f;   
	float fx=x/X0,fy=y/Y0,fz=z/Z0,frx,fry,frz;   
	float k =0.333;   

	if(fx>0.008856) frx=float(pow(fx,k));   
	else frx=7.787f*fx+16.0f/116.0f;   

	if(fy>0.008856) fry=float(pow(fy,k));   
	else fry=7.787f*fy+16.0f/116.0f;   

	if(fz>0.008856) frz=float(pow(fz,k));   
	else frz=7.787f*fz+16.0f/116.0f;   

	if(fx<=0.008856 && fy<=0.008856 && fz<=0.008856)   
	{   
		L=903.3f*fy;   
		u=3893.5f*(fx-fy);   
		v=1557.4f*(fy-fz);   
	}   
	else   
	{   
		L=116*fry-16;   
		u=500*(frx-fry);   
		v=200*(fry-frz);   
	}
}

[stivenjia]

DWORD	__stdcall	HSV2RGB(COLORREF *dwColor,double dValH,double &dValS,double &dValV)
{
	BYTE	var_R = 0,var_G = 0,var_B = 0;
	double	var_h  = 0.0;
	int		var_i  = 0;
	double	var_1 = 0.0,var_2 = 0.0,var_3 = 0.0;
	double	var_r = 0.0,var_g = 0.0,var_b = 0.0;
	if ( 0 < dValS && dValS < 0.0000001 )		//HSV from 0 to 1
	{
		var_R = dValV * 255;
		var_G = dValV * 255;
		var_B = dValV * 255;
	}
	else
	{
		var_h = dValH * 6;
		if ( var_h == 6 ) var_h = 0;      //H must be < 1
		var_i = int( var_h );           //Or ... var_i = floor( var_h )
		var_1 = dValV * ( 1 - dValS );
		var_2 = dValV * ( 1 - dValS * ( var_h - var_i ) );
		var_3 = dValV * ( 1 - dValS * ( 1 - ( var_h - var_i ) ) );

		if( var_i == 0 ) { var_r = dValV     ; var_g = var_3 ; var_b = var_1;	}
		else if ( var_i == 1 ) { var_r = var_2 ; var_g = dValV; var_b = var_1;	}
		else if ( var_i == 2 ) { var_r = var_1 ; var_g = dValV; var_b = var_3;	}
		else if ( var_i == 3 ) { var_r = var_1 ; var_g = var_2; var_b = dValV;	}
		else if ( var_i == 4 ) { var_r = var_3 ; var_g = var_1; var_b = dValV;	}
		else                   { var_r = dValV ; var_g = var_1; var_b = var_2;	}

		var_R = var_r * 255;                  //RGB results from 0 to 255
		var_G = var_g * 255;
		var_B = var_b * 255;
	}
	if(dwColor != NULL)
		*dwColor = RGB(var_R,var_G,var_B);
	return	RGB(var_R,var_G,var_B);
}