tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
Log | Files | Refs | README | LICENSE

tile_common.c (8496B)


      1 /*
      2 * Copyright (c) 2016, Alliance for Open Media. All rights reserved.
      3 *
      4 * This source code is subject to the terms of the BSD 2 Clause License and
      5 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
      6 * was not distributed with this source code in the LICENSE file, you can
      7 * obtain it at www.aomedia.org/license/software. If the Alliance for Open
      8 * Media Patent License 1.0 was not distributed with this source code in the
      9 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
     10 */
     11 
     12 #include <stdbool.h>
     13 
     14 #include "av1/common/av1_common_int.h"
     15 #include "av1/common/resize.h"
     16 #include "av1/common/tile_common.h"
     17 #include "aom_dsp/aom_dsp_common.h"
     18 
     19 void av1_tile_init(TileInfo *tile, const AV1_COMMON *cm, int row, int col) {
     20  av1_tile_set_row(tile, cm, row);
     21  av1_tile_set_col(tile, cm, col);
     22 }
     23 
     24 // Find smallest k>=0 such that (blk_size << k) >= target
     25 static int tile_log2(int blk_size, int target) {
     26  int k;
     27  for (k = 0; (blk_size << k) < target; k++) {
     28  }
     29  return k;
     30 }
     31 
     32 void av1_get_tile_limits(AV1_COMMON *const cm) {
     33  const SequenceHeader *const seq_params = cm->seq_params;
     34  CommonTileParams *const tiles = &cm->tiles;
     35  const int sb_cols =
     36      CEIL_POWER_OF_TWO(cm->mi_params.mi_cols, seq_params->mib_size_log2);
     37  const int sb_rows =
     38      CEIL_POWER_OF_TWO(cm->mi_params.mi_rows, seq_params->mib_size_log2);
     39 
     40  const int sb_size_log2 = seq_params->mib_size_log2 + MI_SIZE_LOG2;
     41  tiles->max_width_sb = MAX_TILE_WIDTH >> sb_size_log2;
     42 
     43 #if CONFIG_CWG_C013
     44  bool use_level_7_above = false;
     45  for (int i = 0; i < seq_params->operating_points_cnt_minus_1 + 1; i++) {
     46    if (seq_params->seq_level_idx[i] >= SEQ_LEVEL_7_0 &&
     47        seq_params->seq_level_idx[i] <= SEQ_LEVEL_8_3) {
     48      // Currently it is assumed that levels 7.x and 8.x are either used for all
     49      // operating points, or none of them.
     50      if (i != 0 && !use_level_7_above) {
     51        aom_internal_error(cm->error, AOM_CODEC_UNSUP_BITSTREAM,
     52                           "Either all the operating points are levels 7.x or "
     53                           "8.x, or none of them are.");
     54      }
     55      use_level_7_above = true;
     56    }
     57  }
     58  const int max_tile_area_sb =
     59      (use_level_7_above ? MAX_TILE_AREA_LEVEL_7_AND_ABOVE : MAX_TILE_AREA) >>
     60      (2 * sb_size_log2);
     61 #else
     62  const int max_tile_area_sb = MAX_TILE_AREA >> (2 * sb_size_log2);
     63 #endif
     64 
     65  tiles->min_log2_cols = tile_log2(tiles->max_width_sb, sb_cols);
     66  tiles->max_log2_cols = tile_log2(1, AOMMIN(sb_cols, MAX_TILE_COLS));
     67  tiles->max_log2_rows = tile_log2(1, AOMMIN(sb_rows, MAX_TILE_ROWS));
     68  tiles->min_log2 = tile_log2(max_tile_area_sb, sb_cols * sb_rows);
     69  tiles->min_log2 = AOMMAX(tiles->min_log2, tiles->min_log2_cols);
     70 }
     71 
     72 void av1_calculate_tile_cols(const SequenceHeader *const seq_params,
     73                             int cm_mi_rows, int cm_mi_cols,
     74                             CommonTileParams *const tiles) {
     75  int sb_cols = CEIL_POWER_OF_TWO(cm_mi_cols, seq_params->mib_size_log2);
     76  int sb_rows = CEIL_POWER_OF_TWO(cm_mi_rows, seq_params->mib_size_log2);
     77  int i;
     78 
     79  // This will be overridden if there is at least two columns of tiles
     80  // (otherwise there is no inner tile width)
     81  tiles->min_inner_width = -1;
     82 
     83  if (tiles->uniform_spacing) {
     84    int start_sb;
     85    int size_sb = CEIL_POWER_OF_TWO(sb_cols, tiles->log2_cols);
     86    assert(size_sb > 0);
     87    for (i = 0, start_sb = 0; start_sb < sb_cols; i++) {
     88      tiles->col_start_sb[i] = start_sb;
     89      start_sb += size_sb;
     90    }
     91    tiles->cols = i;
     92    tiles->col_start_sb[i] = sb_cols;
     93    tiles->min_log2_rows = AOMMAX(tiles->min_log2 - tiles->log2_cols, 0);
     94    tiles->max_height_sb = sb_rows >> tiles->min_log2_rows;
     95 
     96    tiles->width = size_sb << seq_params->mib_size_log2;
     97    tiles->width = AOMMIN(tiles->width, cm_mi_cols);
     98    if (tiles->cols > 1) {
     99      tiles->min_inner_width = tiles->width;
    100    }
    101  } else {
    102    int max_tile_area_sb = (sb_rows * sb_cols);
    103    int widest_tile_sb = 1;
    104    int narrowest_inner_tile_sb = 65536;
    105    tiles->log2_cols = tile_log2(1, tiles->cols);
    106    for (i = 0; i < tiles->cols; i++) {
    107      int size_sb = tiles->col_start_sb[i + 1] - tiles->col_start_sb[i];
    108      widest_tile_sb = AOMMAX(widest_tile_sb, size_sb);
    109      // ignore the rightmost tile in frame for determining the narrowest
    110      if (i < tiles->cols - 1)
    111        narrowest_inner_tile_sb = AOMMIN(narrowest_inner_tile_sb, size_sb);
    112    }
    113    if (tiles->min_log2) {
    114      max_tile_area_sb >>= (tiles->min_log2 + 1);
    115    }
    116    tiles->max_height_sb = AOMMAX(max_tile_area_sb / widest_tile_sb, 1);
    117    if (tiles->cols > 1) {
    118      tiles->min_inner_width = narrowest_inner_tile_sb
    119                               << seq_params->mib_size_log2;
    120    }
    121  }
    122 }
    123 
    124 void av1_calculate_tile_rows(const SequenceHeader *const seq_params,
    125                             int cm_mi_rows, CommonTileParams *const tiles) {
    126  int sb_rows = CEIL_POWER_OF_TWO(cm_mi_rows, seq_params->mib_size_log2);
    127  int start_sb, size_sb, i;
    128 
    129  if (tiles->uniform_spacing) {
    130    size_sb = CEIL_POWER_OF_TWO(sb_rows, tiles->log2_rows);
    131    assert(size_sb > 0);
    132    for (i = 0, start_sb = 0; start_sb < sb_rows; i++) {
    133      tiles->row_start_sb[i] = start_sb;
    134      start_sb += size_sb;
    135    }
    136    tiles->rows = i;
    137    tiles->row_start_sb[i] = sb_rows;
    138 
    139    tiles->height = size_sb << seq_params->mib_size_log2;
    140    tiles->height = AOMMIN(tiles->height, cm_mi_rows);
    141  } else {
    142    tiles->log2_rows = tile_log2(1, tiles->rows);
    143  }
    144 }
    145 
    146 void av1_tile_set_row(TileInfo *tile, const AV1_COMMON *cm, int row) {
    147  assert(row < cm->tiles.rows);
    148  int mi_row_start = cm->tiles.row_start_sb[row]
    149                     << cm->seq_params->mib_size_log2;
    150  int mi_row_end = cm->tiles.row_start_sb[row + 1]
    151                   << cm->seq_params->mib_size_log2;
    152  tile->tile_row = row;
    153  tile->mi_row_start = mi_row_start;
    154  tile->mi_row_end = AOMMIN(mi_row_end, cm->mi_params.mi_rows);
    155  assert(tile->mi_row_end > tile->mi_row_start);
    156 }
    157 
    158 void av1_tile_set_col(TileInfo *tile, const AV1_COMMON *cm, int col) {
    159  assert(col < cm->tiles.cols);
    160  int mi_col_start = cm->tiles.col_start_sb[col]
    161                     << cm->seq_params->mib_size_log2;
    162  int mi_col_end = cm->tiles.col_start_sb[col + 1]
    163                   << cm->seq_params->mib_size_log2;
    164  tile->tile_col = col;
    165  tile->mi_col_start = mi_col_start;
    166  tile->mi_col_end = AOMMIN(mi_col_end, cm->mi_params.mi_cols);
    167  assert(tile->mi_col_end > tile->mi_col_start);
    168 }
    169 
    170 int av1_get_sb_rows_in_tile(const AV1_COMMON *cm, const TileInfo *tile) {
    171  return CEIL_POWER_OF_TWO(tile->mi_row_end - tile->mi_row_start,
    172                           cm->seq_params->mib_size_log2);
    173 }
    174 
    175 int av1_get_sb_cols_in_tile(const AV1_COMMON *cm, const TileInfo *tile) {
    176  return CEIL_POWER_OF_TWO(tile->mi_col_end - tile->mi_col_start,
    177                           cm->seq_params->mib_size_log2);
    178 }
    179 
    180 // Section 7.3.1 of the AV1 spec says, on pages 200-201:
    181 //   It is a requirement of bitstream conformance that the following conditions
    182 //   are met:
    183 //     ...
    184 //     * TileHeight is equal to (use_128x128_superblock ? 128 : 64) for all
    185 //       tiles (i.e. the tile is exactly one superblock high)
    186 //     * TileWidth is identical for all tiles and is an integer multiple of
    187 //       TileHeight (i.e. the tile is an integer number of superblocks wide)
    188 //     ...
    189 bool av1_get_uniform_tile_size(const AV1_COMMON *cm, int *w, int *h) {
    190  const CommonTileParams *const tiles = &cm->tiles;
    191  if (tiles->uniform_spacing) {
    192    *w = tiles->width;
    193    *h = tiles->height;
    194  } else {
    195    for (int i = 0; i < tiles->cols; ++i) {
    196      const int tile_width_sb =
    197          tiles->col_start_sb[i + 1] - tiles->col_start_sb[i];
    198      const int tile_w = tile_width_sb * cm->seq_params->mib_size;
    199      // ensure all tiles have same dimension
    200      if (i != 0 && tile_w != *w) {
    201        return false;
    202      }
    203      *w = tile_w;
    204    }
    205 
    206    for (int i = 0; i < tiles->rows; ++i) {
    207      const int tile_height_sb =
    208          tiles->row_start_sb[i + 1] - tiles->row_start_sb[i];
    209      const int tile_h = tile_height_sb * cm->seq_params->mib_size;
    210      // ensure all tiles have same dimension
    211      if (i != 0 && tile_h != *h) {
    212        return false;
    213      }
    214      *h = tile_h;
    215    }
    216  }
    217  return true;
    218 }
    219 
    220 int av1_is_min_tile_width_satisfied(const AV1_COMMON *cm) {
    221  // Disable check if there is a single tile col in the frame
    222  if (cm->tiles.cols == 1) return 1;
    223 
    224  return ((cm->tiles.min_inner_width << MI_SIZE_LOG2) >=
    225          (64 << av1_superres_scaled(cm)));
    226 }