yuv转opencv中的IplImage

一个小的程序，在网上找了很久没有发现

自己搞了一个大家看看

第一个是很笨的办法：

yuv三个分量分别写在3个矩阵下，然后合并之后转换为rgb分量的图片格式就可以了；

代码如下：

IplImage *image,*rgbimg,*yimg,*uimg,*vimg,*uuimg,*vvimg;

rgbimg =  cvCreateImage(cvSize(nWidth, nHeight),IPL_DEPTH_8U,3);
image = cvCreateImage(cvSize(nWidth, nHeight),IPL_DEPTH_8U,3);

yimg = cvCreateImageHeader(cvSize(nWidth, nHeight),IPL_DEPTH_8U,1);
uimg =  cvCreateImageHeader(cvSize(nWidth/2, nHeight/2),IPL_DEPTH_8U,1);
vimg = cvCreateImageHeader(cvSize(nWidth/2, nHeight/2),IPL_DEPTH_8U,1);

uuimg = cvCreateImage(cvSize(nWidth, nHeight),IPL_DEPTH_8U,1);
vvimg =  cvCreateImage(cvSize(nWidth, nHeight),IPL_DEPTH_8U,1);

cvSetData(yimg,pBuf, nWidth);
cvSetData(uimg,pBuf+nWidth*nHeight, nWidth/2);
cvSetData(vimg,pBuf+long(nWidth*nHeight*1.25), nWidth/2);
cvResize(uimg,uuimg,CV_INTER_LINEAR);
cvResize(vimg,vvimg,CV_INTER_LINEAR);

cvMerge(yimg,uuimg,vvimg,NULL,image);
cvCvtColor(image,rgbimg,CV_YCrCb2BGR);

IplImage *image,*rgbimg,*yimg,*uimg,*vimg,*uuimg,*vvimg;
	
	rgbimg = cvCreateImage(cvSize(nWidth, nHeight),IPL_DEPTH_8U,3);
	image = cvCreateImage(cvSize(nWidth, nHeight),IPL_DEPTH_8U,3);
    
	yimg = cvCreateImageHeader(cvSize(nWidth, nHeight),IPL_DEPTH_8U,1);
	uimg = cvCreateImageHeader(cvSize(nWidth/2, nHeight/2),IPL_DEPTH_8U,1);
	vimg = cvCreateImageHeader(cvSize(nWidth/2, nHeight/2),IPL_DEPTH_8U,1);
    
	uuimg = cvCreateImage(cvSize(nWidth, nHeight),IPL_DEPTH_8U,1);
	vvimg = cvCreateImage(cvSize(nWidth, nHeight),IPL_DEPTH_8U,1);
	
    cvSetData(yimg,pBuf, nWidth);
	cvSetData(uimg,pBuf+nWidth*nHeight, nWidth/2);
	cvSetData(vimg,pBuf+long(nWidth*nHeight*1.25), nWidth/2);
	cvResize(uimg,uuimg,CV_INTER_LINEAR);
	cvResize(vimg,vvimg,CV_INTER_LINEAR);
    
	cvMerge(yimg,uuimg,vvimg,NULL,image);
	cvCvtColor(image,rgbimg,CV_YCrCb2BGR);

还有一个方法就比较负载

首先自己根据原理转换为rgb格式

然后利用cvSetData（）函数写入数据生成IplImage格式的图片

首先定义转换的公式：

#define MR(Y,U,V) (Y + (1.403)*(V-128))
#define MG(Y,U,V) (Y - (0.344) * (U-128) - (0.714) * (V-128) )
#define MB(Y,U,V) (Y + ((1.773) * (U-128)))

#define MR(Y,U,V) (Y + (1.403)*(V-128))
#define MG(Y,U,V) (Y - (0.344) * (U-128) - (0.714) * (V-128) ) 
#define MB(Y,U,V) (Y + ((1.773) * (U-128)))

yuv转rgb的函数：

void YUV420_C_RGB( char* pYUV, unsigned char* pRGB, int height, int width)
{
char* pY =  pYUV;
char* pU = pYUV+height*width;
char* pV =  pU+(height*width/4);


unsigned char* pBGR =  NULL;
unsigned char R =  0;
unsigned char G =  0;
unsigned char B =  0;
char Y = 0;
char U =  0;
char V = 0;
double tmp =  0;
for ( int i = 0; i<height; ++i )
{
for ( int j = 0; j<width; ++j )
{
pBGR = pRGB+ i*width*3+j*3;

Y = *(pY+i*width+j);
U = *pU;
V = *pV;

//B
tmp =  MB(Y, U, V);
//B = (tmp > 255) ? 255 : (char)tmp;
//B = (B<0) ? 0 : B;
B = (unsigned char)tmp;
//G
tmp = MG(Y, U, V);
//G = (tmp > 255) ? 255 : (char)tmp;
// G = (G<0) ? 0 : G;
G = (unsigned char)tmp;
//R
tmp =  MR(Y, U, V);
//R = (tmp > 255) ? 255 : (char)tmp;
//R = (R<0) ? 0 : R;
R = (unsigned char)tmp;


*pBGR =  R;
*(pBGR+1) = G;
*(pBGR+2) = B;


if ( i%2 == 0 && j%2 == 0)
{
*pU++;
//*pV++;
}
else
{
if ( j%2 == 0 )
{
*pV++ ;
}
}
}

}
}

void YUV420_C_RGB( char* pYUV, unsigned char* pRGB, int height, int width)
{
    char* pY = pYUV;
    char* pU = pYUV+height*width;
    char* pV = pU+(height*width/4);


    unsigned char* pBGR = NULL;
    unsigned char R = 0;
    unsigned char G = 0;
    unsigned char B = 0;
    char Y = 0;
    char U = 0;
    char V = 0;
    double tmp = 0;
    for ( int i = 0; i < height; ++i )
    {
        for ( int j = 0; j < width; ++j )
        {
            pBGR = pRGB+ i*width*3+j*3;

            Y = *(pY+i*width+j);
            U = *pU;
            V = *pV;

            //B
            tmp = MB(Y, U, V);
            //B = (tmp > 255) ? 255 : (char)tmp;
            //B = (B<0) ? 0 : B;
			B = (unsigned char)tmp;
            //G
            tmp = MG(Y, U, V);
            //G = (tmp > 255) ? 255 : (char)tmp;
           // G = (G<0) ? 0 : G;
			G = (unsigned char)tmp;
            //R
            tmp = MR(Y, U, V);
            //R = (tmp > 255) ? 255 : (char)tmp;
            //R = (R<0) ? 0 : R;
			R = (unsigned char)tmp;


            *pBGR     = R;            
            *(pBGR+1) = G;        
            *(pBGR+2) = B;
        

            if ( i%2 == 0 && j%2 == 0)
            {
                *pU++;
				//*pV++;
            }
            else
            {
                if ( j%2 == 0 )
                {
                    *pV++ ;
                }
			}
        }
    
    }
}

最后是写入IplImage的代码：

unsigned char* pRGB =  NULL;

pRGB = (unsigned char*)malloc(nSize*sizeof(unsigned char*)*2);

YUV420_C_RGB(pBuf,pRGB,nWidth,nHeight);

IplImage *image;
image = cvCreateImageHeader(cvSize(nWidth, nHeight),IPL_DEPTH_8U,3);
cvSetData(image,pRGB,nWidth*3);

unsigned char* pRGB = NULL;

pRGB = (unsigned char*)malloc(nSize*sizeof(unsigned char*)*2);
	
YUV420_C_RGB(pBuf,pRGB,nWidth,nHeight);
	
IplImage *image;
image = cvCreateImageHeader(cvSize(nWidth, nHeight),IPL_DEPTH_8U,3);
cvSetData(image,pRGB,nWidth*3);

程序都运行过

编译环境为vs2008

opencv2.0版本

另外，附上RGB转YUV420格式的代码：

#define MY(R,G,B) ((0.299)*R + (0.587)*G + (0.114)*B)
#define MU(R,G,B) (-(0.169)*R - (0.332)*G+ (0.501)*B)
#define MV(R,G,B) ( (0.450)*R - (0.419)*G - (0.081)*B )

#define MR(Y,U,V) (Y + (1.403)*V)
#define MG(Y,U,V) (Y - ( (0.3455) * U - ( (0.7169) * V ) ) )
#define MB(Y,U,V) (Y + ((1.7790) * U))

/**************************rgb->yuv420*************************************/
void RGB_C_YUV420( char * pRGB, char * pYUV, int height, int width)
{
char * pY = pYUV;
char * pU = pYUV+height*width;
char * pV = pU+(height*width/4);

char * pBGR = NULL;
char R = 0;
char G = 0;
char B = 0;
char Y = 0;
char U = 0;
char V = 0;
double tmp = 0;
for ( int i = 0; i < height; ++i )
{
for ( int j = 0; j < width; ++j )
{
pBGR = pRGB+ i*width*3+j*3;
B = *pBGR;
G = *(pBGR+1);
R = *(pBGR+2);
//Y
Y = MY(R,G,B);
//U
U = MU(R,G,B);
//V
V = MV(R,G,B);

*(pY+i*width+j) = Y;

if ( i%2 == 0 && j%2 == 0)
{
*pU = U;
pU++;
}
else
{
if ( j%2 == 0 )
{
*pV++ = V;
}
}
}
}


}