RGB与YCbCr颜色空间的转换

原文：http://www.cnblogs.com/starspace/archive/2008/12/16/1356007.html

公式如下：//数字RGB与YCbCr颜色空间转换的精度? //在这两个公式中RGB和YCbCr各分量的值的范围均为0-255。// RGB转换为YCbCr// 这个公式来自：Genesis Microchip. gm6010/gm6015 Programming Guide[M]. California US: Genesis Microchip Company, 2002:85-90// |Y?? |????|16??|????????????????? ? |65.738?? 129.057? 25.06?|?? |R|
// |Cb| = |128| + (1/256)*|-37.945? -74.494? 112.43| *|G|
// |Cr |????|128|???????????????????|112.439? -94.154? -18.28|?? |B|// YCbCr转换为RGB// 这个公式来自：Genesis Microchip. gm6015 Preliminary Data Sheet[M]. California US: Genesis Microchip Company, 2001:33-34
//|R|???????????????????|298.082 ?0?????????????? 408.58 |? ?|Y???-16? |
//|G| = (1/256)*|298.082? -100.291 -208.12|* |Cb-128|
//|B|?????????????????? |298.082? 516.411?? 0?????????? |?? |Cr -128| ?加一点我的代码，为什么要加我的代码呢，不是因为写的代码好，只不过是我把上面公式中的矩阵/256算成小数了，这样子我们可以省点时间：?

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// RGB转换为YCbCrfor(i =0 ; i < dest->dwSize; ){ UCHAR r,g,b; r = sBuf[i+0]; g = sBuf[i+1]; b = sBuf[i+2]; dBuf[i+0]= (unsigned char)(r * 0.256789 + g * 0.504129 + b * 0.097906)+ 16;  dBuf[i+1]= (unsigned char)(r *-0.148223 + g * -0.290992 + b * 0.439215)+ 128; dBuf[i+2]= (unsigned char)(r * 0.439215 + g * -0.367789 + b *-0.071426)+ 128;  i += 3;}

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// YCbCr转换为RGBfor(i =0 ; i < dest->dwSize; ){ UCHAR y,u,v; y = sBuf[i+0]; u = sBuf[i+1]; v = sBuf[i+2]; dBuf[i+0]= (unsigned char)(1.164383*(y- 16) + 0 + 1.596027*(v - 128));  dBuf[i+1]= (unsigned char)(1.164383*(y- 16) - 0.391762*(u - 128) - 0.812969*(v - 128));  dBuf[i+2]= (unsigned char)(1.164383*(y- 16) + 2.017230*(u - 128) + 0 ); i += 3;}

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