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 18 static int to_sbs(n_mis) { 19 return mi_cols_aligned_to_sb(n_mis) >> MI_BLOCK_SIZE_LOG2; 20 } 21 22 static void get_tile_offsets(int *min_tile_off, int *max_tile_off, 23 int tile_idx, int log2_n_tiles, int n_mis) { 24 const int n_sbs = to_sbs(n_mis); 25 const int sb_off1 = (tile_idx * n_sbs) >> log2_n_tiles; 26 const int sb_off2 = ((tile_idx + 1) * n_sbs) >> log2_n_tiles; 27 28 *min_tile_off = MIN(sb_off1 << 3, n_mis); 29 *max_tile_off = MIN(sb_off2 << 3, n_mis); 30 } 31 32 void vp9_tile_init(TileInfo *tile, const VP9_COMMON *cm, 33 int row_idx, int col_idx) { 34 get_tile_offsets(&tile->mi_row_start, &tile->mi_row_end, 35 row_idx, cm->log2_tile_rows, cm->mi_rows); 36 get_tile_offsets(&tile->mi_col_start, &tile->mi_col_end, 37 col_idx, cm->log2_tile_cols, cm->mi_cols); 38 } 39 40 void vp9_get_tile_n_bits(int mi_cols, 41 int *min_log2_tile_cols, int *max_log2_tile_cols) { 42 const int sb_cols = to_sbs(mi_cols); 43 int min_log2_n_tiles, max_log2_n_tiles; 44 45 for (max_log2_n_tiles = 0; 46 (sb_cols >> max_log2_n_tiles) >= MIN_TILE_WIDTH_B64; 47 max_log2_n_tiles++) {} 48 max_log2_n_tiles--; 49 if (max_log2_n_tiles < 0) 50 max_log2_n_tiles = 0; 51 52 for (min_log2_n_tiles = 0; 53 (MAX_TILE_WIDTH_B64 << min_log2_n_tiles) < sb_cols; 54 min_log2_n_tiles++) {} 55 56 assert(min_log2_n_tiles <= max_log2_n_tiles); 57 58 *min_log2_tile_cols = min_log2_n_tiles; 59 *max_log2_tile_cols = max_log2_n_tiles; 60 } 61