yuv420转rgba

yuv420转rgba,yuv420内存排列为yyyy,u,v
 

bool yuv420ToRgb(uint8_t* yuv, int w, int h, uint8_t* rgb)
{
    uint8_t* pBufy = new uint8_t[w * h];
    uint8_t* pBufu = new uint8_t[w * h / 4];
    uint8_t* pBufv = new uint8_t[w * h / 4];

    memcpy(pBufy, yuv, w * h);
    memcpy(pBufu, yuv + w * h, w * h / 4);
    memcpy(pBufv, yuv + w * h * 5 / 4, w * h / 4);


    for (int y = 0; y < h; y++)
    {
        for (int x = 0; x < w; x++)
        {
            int r = (int)(pBufy[y * w + x] + 1.370705 * (pBufv[y * w / 4 + x / 
            int g = (int)(pBufy[y * w + x] - 0.698001 * (pBufu[y * w / 4 + x / 2] - 128) - 0.703125 * (pBufv[y * w / 4 + x / 2] - 128));
            int b = (int)(pBufy[y * w + x] + 1.732446 * (pBufu[y * w / 4 + x / 2] - 128));

            if (r > 255)
                r = 255;
            if (r < 0)
                r = 0;
            if (g > 255)
                g = 255;
            if (g < 0)
                g = 0;
            if (b > 255)
                b = 255;
            if (b < 0)
   
            free(pBufy);
            free(pBufu);
            free(pBufv);
            return true;
          }


      }
}