VP9_SUPER_FRAME_BS_SZ
unsigned char sf_bs_buf[VP9_SUPER_FRAME_BS_SZ];
sf_bs_sz = bs->size > VP9_SUPER_FRAME_BS_SZ ?
VP9_SUPER_FRAME_BS_SZ : bs->size;
sf_bs_off = VP9_SUPER_FRAME_BS_SZ - sf_bs_sz;