diff -r 000000000000 -r 6474c204b198 media/libvpx/vp9/common/vp9_tile_common.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/media/libvpx/vp9/common/vp9_tile_common.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,29 @@
+/*
+ *  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.
+ */
+
+#ifndef VP9_COMMON_VP9_TILE_COMMON_H_
+#define VP9_COMMON_VP9_TILE_COMMON_H_
+
+struct VP9Common;
+
+typedef struct TileInfo {
+  int mi_row_start, mi_row_end;
+  int mi_col_start, mi_col_end;
+} TileInfo;
+
+// initializes 'tile->mi_(row|col)_(start|end)' for (row, col) based on
+// 'cm->log2_tile_(rows|cols)' & 'cm->mi_(rows|cols)'
+void vp9_tile_init(TileInfo *tile, const struct VP9Common *cm,
+                   int row, int col);
+
+void vp9_get_tile_n_bits(int mi_cols,
+                         int *min_log2_tile_cols, int *max_log2_tile_cols);
+
+#endif  // VP9_COMMON_VP9_TILE_COMMON_H_