FFMPEG 内部 YUV444P016 -> P010

1. hscale 

　　计算结果的时候 14 + %1 - %2    //m0 >> 14 + 16-15   m0 >>= 15 

2. vscale   // 这里的输入实际上是 高12位数据， 0-4096

static void yuv2p010cX_c(SwsContext *c, const int16_t *chrFilter, int chrFilterSize,
                         const int16_t **chrUSrc, const int16_t **chrVSrc,
                         uint8_t *dest8, int chrDstW)
{
    uint16_t *dest = (uint16_t*)dest8;
    int shift = 17;
    int big_endian = c->dstFormat == AV_PIX_FMT_P010BE;
    int i, j;

    for (i = 0; i < chrDstW; i++) {
        int u = 1 << (shift - 1);
        int v = 1 << (shift - 1);

        for (j = 0; j < chrFilterSize; j++) {
            u += chrUSrc[j][i] * chrFilter[j];
            v += chrVSrc[j][i] * chrFilter[j];
        }

        output_pixel(&dest[2*i]  , u);   //AV_WL16(pos, av_clip_uintp2(val >> shift, 10) << 6);  ((u >> 17)<<6)

        output_pixel(&dest[2*i+1], v);
    }
}

yuv2plane1 = 0x480860 <yuv2p010l1_LE_c>

yuv2planeX = 0x4a6580 <yuv2p010lX_LE_c>

yuv2nv12cX = 0x4806e0 <yuv2p010cX_c>

hyScale = 0x4c5520 <ff_hscale16to15_4_ssse3>

hcScale = 0x4c55a0 <ff_hscale16to15_8_ssse3>