yuyv轉rgb，rgb轉bmp，已驗證

#define VIDEO_DEVICE "/dev/video1"
#define IMAGE_WIDTH 1280
#define IMAGE_HEIGHT 720
#define IMAGE_SIZE (IMAGE_WIDTH * IMAGE_HEIGHT *2)
#define BUFFER_COUNT 5

typedef long LONG;  
typedef unsigned long DWORD;  
typedef unsigned short WORD;  
  
typedef struct {  
        //WORD    bfType;  
        DWORD   bfSize;  
        WORD    bfReserved1;  
        WORD    bfReserved2;  
        DWORD   bfOffBits;  
} BMPFILEHEADER_T;  
  
typedef struct{  
        DWORD      biSize;  
        LONG       biWidth;  
        LONG       biHeight;  
        WORD       biPlanes;  
        WORD       biBitCount;  
        DWORD      biCompression;  
        DWORD      biSizeImage;  
        LONG       biXPelsPerMeter;  
        LONG       biYPelsPerMeter;  
        DWORD      biClrUsed;  
        DWORD      biClrImportant;  
} BMPINFOHEADER_T;  

void yuyv_to_rgb(unsigned char* yuv,unsigned char* rgb)
{
    unsigned int i;
    unsigned char* y0 = yuv + 0;   
    unsigned char* u0 = yuv + 1;
    unsigned char* y1 = yuv + 2;
    unsigned char* v0 = yuv + 3;

    unsigned  char* r0 = rgb + 0;
    unsigned  char* g0 = rgb + 1;
    unsigned  char* b0 = rgb + 2;
    unsigned  char* r1 = rgb + 3;
    unsigned  char* g1 = rgb + 4;
    unsigned  char* b1 = rgb + 5;
	DBG("yuyv_to_rgb start\n");
    float rt0 = 0, gt0 = 0, bt0 = 0, rt1 = 0, gt1 = 0, bt1 = 0;

    for(i = 0; i <= (IMAGE_WIDTH * IMAGE_HEIGHT) / 2 ;i++)
    {
        bt0 = 1.164 * (*y0 - 16) + 2.018 * (*u0 - 128); 
        gt0 = 1.164 * (*y0 - 16) - 0.813 * (*v0 - 128) - 0.394 * (*u0 - 128); 
        rt0 = 1.164 * (*y0 - 16) + 1.596 * (*v0 - 128); 
   
    	bt1 = 1.164 * (*y1 - 16) + 2.018 * (*u0 - 128); 
        gt1 = 1.164 * (*y1 - 16) - 0.813 * (*v0 - 128) - 0.394 * (*u0 - 128); 
        rt1 = 1.164 * (*y1 - 16) + 1.596 * (*v0 - 128); 
      
       	if(rt0 > 250)  	rt0 = 255;
		if(rt0 < 0)    	rt0 = 0;	

		if(gt0 > 250) 	gt0 = 255;
		if(gt0 < 0)	gt0 = 0;	

		if(bt0 > 250)	bt0 = 255;
		if(bt0 < 0)	bt0 = 0;	

		if(rt1 > 250)	rt1 = 255;
		if(rt1 < 0)	rt1 = 0;	

		if(gt1 > 250)	gt1 = 255;
		if(gt1 < 0)	gt1 = 0;	

		if(bt1 > 250)	bt1 = 255;
		if(bt1 < 0)	bt1 = 0;	
					
		*r0 = (unsigned char)rt0;
		*g0 = (unsigned char)gt0;
		*b0 = (unsigned char)bt0;
	
		*r1 = (unsigned char)rt1;
		*g1 = (unsigned char)gt1;
		*b1 = (unsigned char)bt1;

        yuv = yuv + 4;
        rgb = rgb + 6;
        if(yuv == NULL)
          break;

        y0 = yuv;
        u0 = yuv + 1;
        y1 = yuv + 2;
        v0 = yuv + 3;
  
        r0 = rgb + 0;
        g0 = rgb + 1;
        b0 = rgb + 2;
        r1 = rgb + 3;
        g1 = rgb + 4;
        b1 = rgb + 5;
    }   
	DBG("yuyv_to_rgb end\n");
}

int rgb_to_bmp(unsigned char* pdata,  const char *pFileName, int width, int height)     
{
    int32_t ret = 0;
	FILE *bmp_fd = NULL;

    //分別爲rgb數據，要保存的bmp文件名 
    int size = width*height*3*sizeof(char); // 每個像素點3個字節   
    // 位圖第一部分，文件信息  
    BMPFILEHEADER_T bfh;  
	
	 bmp_fd = fopen(pFileName, "wb");
	if (NULL == bmp_fd)
	{
		ret = -3;
		return ret;
	}
	
	//bfh.bfType = (unsigned short)0x4d42;  //bm  
	unsigned short bfType=0x4d42; 
    bfh.bfSize = size  // data size  
        + sizeof( BMPFILEHEADER_T ) // first section size  
        + sizeof( BMPINFOHEADER_T ) // second section size  
        ;  
	printf("sizeof( BMPFILEHEADER_T )== %ld,sizeof( BMPINFOHEADER_T )=%ld\n", sizeof( BMPFILEHEADER_T ),sizeof( BMPINFOHEADER_T ));
    bfh.bfReserved1 = 0; // reserved  
    bfh.bfReserved2 = 0; // reserved  
    bfh.bfOffBits = sizeof( BMPFILEHEADER_T )+ sizeof( BMPINFOHEADER_T );//真正的數據的位置 
    printf("bmp_head== %ld\n", bfh.bfOffBits); 
    // 位圖第二部分，數據信息  
    BMPINFOHEADER_T bih;  
    bih.biSize = sizeof(BMPINFOHEADER_T);  
    bih.biWidth = width;  
    bih.biHeight = -height;//BMP圖片從最後一個點開始掃描，顯示時圖片是倒着的，所以用-height，這樣圖片就正了  
    bih.biPlanes = 1;//爲1，不用改  
    bih.biBitCount = 24;  
    bih.biCompression = 0;//不壓縮  
    bih.biSizeImage = size;  

    bih.biXPelsPerMeter = 0;//像素每米  
  
    bih.biYPelsPerMeter = 0;  
    bih.biClrUsed = 0;//已用過的顏色，爲0,與bitcount相同  
    bih.biClrImportant = 0;//每個像素都重要  
	
    fwrite(&bfType,sizeof(bfType),1,bmp_fd); 
    fwrite( &bfh, 6, 1, bmp_fd); 
    fwrite(&bfh.bfReserved2, sizeof(bfh.bfReserved2), 1, bmp_fd);  
    fwrite(&bfh.bfOffBits, sizeof(bfh.bfOffBits), 1, bmp_fd);  
    fwrite(&bih, sizeof(BMPINFOHEADER_T), 1, bmp_fd);  
	
    fwrite(pdata, size, 1, bmp_fd);   
	if (NULL != bmp_fd)
    {
        fclose(bmp_fd);
        bmp_fd = NULL;
    }
	return ret;
}