const int big_mb_num= h->mb_stride * (s->mb_height+1);
const int big_mb_num= s->mb_stride * (s->mb_height+1);
static int alloc_tables(H264Context *h){    MpegEncContext * const s = &h->s;    const int big_mb_num= h->mb_stride * (s->mb_height+1);    int x,y;    CHECKED_ALLOCZ(h->intra4x4_pred_mode, big_mb_num * 8  * sizeof(uint8_t))    CHECKED_ALLOCZ(h->non_zero_count    , big_mb_num * 16 * sizeof(uint8_t))    CHECKED_ALLOCZ(h->slice_table_base  , big_mb_num * sizeof(uint8_t))    memset(h->slice_table_base, -1, big_mb_num  * sizeof(uint8_t));    h->slice_table= h->slice_table_base + h->mb_stride + 1;    CHECKED_ALLOCZ(h->mb2b_xy  , big_mb_num * sizeof(uint16_t));    CHECKED_ALLOCZ(h->mb2b8_xy , big_mb_num * sizeof(uint16_t));    for(y=0; y<s->mb_height; y++){        for(x=0; x<s->mb_width; x++){            const int mb_xy= x + y*h->mb_stride;            const int b_xy = 4*x + 4*y*h->b_stride;            const int b8_xy= 2*x + 2*y*h->b8_stride;                    h->mb2b_xy [mb_xy]= b_xy;            h->mb2b8_xy[mb_xy]= b8_xy;        }    }        return 0;fail:    free_tables(h);    return -1;}