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 /*

  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.

  *

  *  Use of this source code is governed by a BSD-style license

  *  that can be found in the LICENSE file in the root of the source

  *  tree. An additional intellectual property rights grant can be found

  *  in the file PATENTS.  All contributing project authors may

  *  be found in the AUTHORS file in the root of the source tree.

  */

 #include "vp9/common/vp9_tile_common.h"

 #include "vp9/common/vp9_onyxc_int.h"

 #define MIN_TILE_WIDTH_B64 4

 #define MAX_TILE_WIDTH_B64 64

 static int get_tile_offset(int idx, int mis, int log2) {

   const int sb_cols = mi_cols_aligned_to_sb(mis) >> MI_BLOCK_SIZE_LOG2;

   const int offset = ((idx * sb_cols) >> log2) << MI_BLOCK_SIZE_LOG2;

   return MIN(offset, mis);

 }

 void vp9_tile_init(TileInfo *tile, const VP9_COMMON *cm, int row, int col) {

   tile->mi_row_start = get_tile_offset(row, cm->mi_rows, cm->log2_tile_rows);

   tile->mi_row_end = get_tile_offset(row + 1, cm->mi_rows, cm->log2_tile_rows);

   tile->mi_col_start = get_tile_offset(col, cm->mi_cols, cm->log2_tile_cols);

   tile->mi_col_end = get_tile_offset(col + 1, cm->mi_cols, cm->log2_tile_cols);

 }

 void vp9_get_tile_n_bits(int mi_cols,

                          int *min_log2_tile_cols, int *max_log2_tile_cols) {

   const int sb_cols = mi_cols_aligned_to_sb(mi_cols) >> MI_BLOCK_SIZE_LOG2;

   int min_log2 = 0, max_log2 = 0;

   // max

   while ((sb_cols >> max_log2) >= MIN_TILE_WIDTH_B64)

     ++max_log2;

   --max_log2;

   if (max_log2 < 0)

     max_log2 = 0;

   // min

   while ((MAX_TILE_WIDTH_B64 << min_log2) < sb_cols)

     ++min_log2;

   assert(min_log2 <= max_log2);

   *min_log2_tile_cols = min_log2;

   *max_log2_tile_cols = max_log2;

 }