vp9/encoder/vp9_treewriter.h

   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 #ifndef VP9_ENCODER_VP9_TREEWRITER_H_
  12 #define VP9_ENCODER_VP9_TREEWRITER_H_
  13
  14 #include "vpx_dsp/bitwriter.h"
  15
  16 #ifdef __cplusplus
  17 extern "C" {
  18 #endif
  19
  20 void vp9_tree_probs_from_distribution(vp9_tree tree,
  21                                       unsigned int branch_ct[ /* n - 1 */ ][2],
  22                                       const unsigned int num_events[ /* n */ ]);
  23
  24 struct vp9_token {
  25   int value;
  26   int len;
  27 };
  28
  29 void vp9_tokens_from_tree(struct vp9_token*, const vp9_tree_index *);
  30
  31 static INLINE void vp9_write_tree(vp9_writer *w, const vp9_tree_index *tree,
  32                                   const vpx_prob *probs, int bits, int len,
  33                                   vp9_tree_index i) {
  34   do {
  35     const int bit = (bits >> --len) & 1;
  36     vp9_write(w, bit, probs[i >> 1]);
  37     i = tree[i + bit];
  38   } while (len);
  39 }
  40
  41 static INLINE void vp9_write_token(vp9_writer *w, const vp9_tree_index *tree,
  42                                    const vpx_prob *probs,
  43                                    const struct vp9_token *token) {
  44   vp9_write_tree(w, tree, probs, token->value, token->len, 0);
  45 }
  46
  47 #ifdef __cplusplus
  48 }  // extern "C"
  49 #endif
  50
  51 #endif  // VP9_ENCODER_VP9_TREEWRITER_H_