YUV轉RGB函數

以下是YUV420轉RGB24函數，有試過可以的，其中參數
src0 是Y量的起始指針， src1 是U量的起始指針 ， src2是 V量的起始指針
dst_ori 是RGB buffer的起始指針
width 爲寬，height 爲高

對於YUV420格式數據的YUV量分配分別是
Y量爲 數據的起始指針
U量爲 數據的起始指針 + 寬*高
V量爲 數據的起始指針 + 寬*高*5/4

void ConvertYUVtoRGB(unsigned char *src0,unsigned char *src1,unsigned char *src2,unsigned char *dst_ori,int width, int height)
{
  extern long int crv_tab[];
  extern long int cbu_tab[];
  extern long int cgu_tab[];

  extern long int cgv_tab[];
  extern long int tab_76309[];

  int y11, y21;
  int y12, y22;
  int y13, y23;
  int y14, y24;
  int u, v;
  int i, j;
  int c11, c21, c31, c41;
  int c12, c22, c32, c42;
  unsigned int DW;
  unsigned int *id1, *id2;
  unsigned char *py1, *py2, *pu, *pv;
  unsigned char *d1, *d2;

  d1 = dst_ori;
  d1 += width * height * 3 - width * 3;
  d2 = d1 - width * 3;

  py1 = src0;
  pu = src1;
  pv = src2;
  py2 = py1 + width;

  id1 = (unsigned int *) d1;
  id2 = (unsigned int *) d2;

  for (j = 0; j < height; j += 2)

  {
    /* line j + 0 */
    for (i = 0; i < width; i += 4)
    {
      u = *pu++;
      v = *pv++;
      c11 = crv_tab[v];
      c21 = cgu_tab[u];
      c31 = cgv_tab[v];
      c41 = cbu_tab[u];
      u = *pu++;
      v = *pv++;
      c12 = crv_tab[v];
      c22 = cgu_tab[u];
      c32 = cgv_tab[v];
      c42 = cbu_tab[u];

 

      y11 = tab_76309[*py1++];  /* (255/219)*65536 */
      y12 = tab_76309[*py1++];
      y13 = tab_76309[*py1++];  /* (255/219)*65536 */
      y14 = tab_76309[*py1++];

 

      y21 = tab_76309[*py2++];
      y22 = tab_76309[*py2++];
      y23 = tab_76309[*py2++];
      y24 = tab_76309[*py2++];

 

      /* RGBR */
      DW = ((clp[(y11 + c41) >> 16])) |
        ((clp[(y11 - c21 - c31) >> 16]) << 8) |
        ((clp[(y11 + c11) >> 16]) << 16) |
        ((clp[(y12 + c41) >> 16]) << 24);
      *id1++ = DW;

 

      /* GBRG */
      DW = ((clp[(y12 - c21 - c31) >> 16])) |
        ((clp[(y12 + c11) >> 16]) << 8) |
        ((clp[(y13 + c42) >> 16]) << 16) |
        ((clp[(y13 - c22 - c32) >> 16]) << 24);
      *id1++ = DW;

 

      /* BRGB */
      DW = ((clp[(y13 + c12) >> 16])) |
        ((clp[(y14 + c42) >> 16]) << 8) |
        ((clp[(y14 - c22 - c32) >> 16]) << 16) |
        ((clp[(y14 + c12) >> 16]) << 24);
      *id1++ = DW;

 

      /* RGBR */
      DW = ((clp[(y21 + c41) >> 16])) |
        ((clp[(y21 - c21 - c31) >> 16]) << 8) |
        ((clp[(y21 + c11) >> 16]) << 16) |
        ((clp[(y22 + c41) >> 16]) << 24);
      *id2++ = DW;

 

      /* GBRG */
      DW = ((clp[(y22 - c21 - c31) >> 16])) |
        ((clp[(y22 + c11) >> 16]) << 8) |
        ((clp[(y23 + c42) >> 16]) << 16) |
        ((clp[(y23 - c22 - c32) >> 16]) << 24);
      *id2++ = DW;

 

      /* BRGB */
      DW = ((clp[(y23 + c12) >> 16])) |
        ((clp[(y24 + c42) >> 16]) << 8) |
        ((clp[(y24 - c22 - c32) >> 16]) << 16) |
        ((clp[(y24 + c12) >> 16]) << 24);
      *id2++ = DW;
    }
    id1 -= (9 * width) >> 2;
    id2 -= (9 * width) >> 2;
    py1 += width;
    py2 += width;
  }
}