RefPicList *ff_hevc_get_ref_list(HEVCContext *s, HEVCFrame *ref, int x0, int y0)
{
    int x_cb         = x0 >> s->sps->log2_ctb_size;
    int y_cb         = y0 >> s->sps->log2_ctb_size;
    int pic_width_cb = (s->sps->width + (1 << s->sps->log2_ctb_size) - 1) >>
        s->sps->log2_ctb_size;
    int ctb_addr_ts  = s->pps->ctb_addr_rs_to_ts[y_cb * pic_width_cb + x_cb];
    return (RefPicList *)ref->rpl_tab[ctb_addr_ts];
}