static void FUNCC(pred4x4_top_dc)(uint8_t *_src, const uint8_t *topright, int _stride){
    pixel *src = (pixel*)_src;
    int stride = _stride/sizeof(pixel);
    const int dc= (  src[-stride] + src[1-stride] + src[2-stride] + src[3-stride] + 2) >>2;

    ((pixel4*)(src+0*stride))[0]=
    ((pixel4*)(src+1*stride))[0]=
    ((pixel4*)(src+2*stride))[0]=
    ((pixel4*)(src+3*stride))[0]= PIXEL_SPLAT_X4(dc);
}