我需要将RGB转换为YCbCr,这是我的毕业项目,我尝试用以下方式实现(我使用C语言编程):
/* Autor: Vinicius Garcia
* Data : 09.ago.2011
*
* Função que converte um pixel RGB em YCbCr
*
* param : int R valor do pixel no canal red
* param : int G valor do pixel no canal green
* param : int B valor do pixel no canal blue
* return: int* vetor de inteiros com os valores H, S e V calculados - nesta ordem
*/
int* converter_RGB_para_YCbCr(int R, int G, int B){
int* YCbCr = (int*) malloc(3 * sizeof(int));
double delta = 128.0; //Constante necessaria para o calculo da conversão de cor
double Y = (0.299 * R + 0.587 * G + 0.114 * B);
double Cb = ((B - Y) * 0.564 + delta);
double Cr = ((R - Y) * 0.713 + delta);
YCbCr[0] = (int) Y;
YCbCr[1] = (int) Cb;
YCbCr[2] = (int) Cr;
return YCbCr;
}
但是它对我没用!
我正在与OpenCv库中的cvCvtColor进行比较,结果不匹配:
R = 88, G = 76, B = 78
cvCvtColor: Y = 80, Cb = 127, Cr = 134
myfunction: Y = 382, Cb = 132, Cr = 132 (cr and cr are always equal!)
我真的需要你的帮助,我尝试了很长时间,但是对我的疑问没有找到任何答案。
你们认为我获取RGB值的方式有问题吗?我的方法是这样的:
uchar B = CV_IMAGE_ELEM(img_RGB, uchar, linha, coluna * 3);
uchar G = CV_IMAGE_ELEM(img_RGB, uchar, linha, coluna * 3 + 1);
uchar R = CV_IMAGE_ELEM(img_RGB, uchar, linha, coluna * 3 + 2);
那么我会这样调用我的转换函数:
converter_RGB_para_YCbCr(R, G, B);
我的函数需要int R,int G,int B,但我正在传递uchar B,uchar G,uchar R。这样可以吗?