1/*
2 *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
3 *
4 *  Use of this source code is governed by a BSD-style license
5 *  that can be found in the LICENSE file in the root of the source
6 *  tree. An additional intellectual property rights grant can be found
7 *  in the file PATENTS.  All contributing project authors may
8 *  be found in the AUTHORS file in the root of the source tree.
9 */
10
11#include "vp9/common/vp9_tile_common.h"
12
13#include "vp9/common/vp9_onyxc_int.h"
14
15#define MIN_TILE_WIDTH_B64 4
16#define MAX_TILE_WIDTH_B64 64
17
18static int get_tile_offset(int idx, int mis, int log2) {
19  const int sb_cols = mi_cols_aligned_to_sb(mis) >> MI_BLOCK_SIZE_LOG2;
20  const int offset = ((idx * sb_cols) >> log2) << MI_BLOCK_SIZE_LOG2;
21  return MIN(offset, mis);
22}
23
24void vp9_tile_init(TileInfo *tile, const VP9_COMMON *cm, int row, int col) {
25  tile->mi_row_start = get_tile_offset(row, cm->mi_rows, cm->log2_tile_rows);
26  tile->mi_row_end = get_tile_offset(row + 1, cm->mi_rows, cm->log2_tile_rows);
27  tile->mi_col_start = get_tile_offset(col, cm->mi_cols, cm->log2_tile_cols);
28  tile->mi_col_end = get_tile_offset(col + 1, cm->mi_cols, cm->log2_tile_cols);
29}
30
31void vp9_get_tile_n_bits(int mi_cols,
32                         int *min_log2_tile_cols, int *max_log2_tile_cols) {
33  const int sb_cols = mi_cols_aligned_to_sb(mi_cols) >> MI_BLOCK_SIZE_LOG2;
34  int min_log2 = 0, max_log2 = 0;
35
36  // max
37  while ((sb_cols >> max_log2) >= MIN_TILE_WIDTH_B64)
38    ++max_log2;
39  --max_log2;
40  if (max_log2 < 0)
41    max_log2 = 0;
42
43  // min
44  while ((MAX_TILE_WIDTH_B64 << min_log2) < sb_cols)
45    ++min_log2;
46
47  assert(min_log2 <= max_log2);
48
49  *min_log2_tile_cols = min_log2;
50  *max_log2_tile_cols = max_log2;
51}
52