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(vpx_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 vpx_tree_index *);
30 
vp9_write_tree(vpx_writer * w,const vpx_tree_index * tree,const vpx_prob * probs,int bits,int len,vpx_tree_index i)31 static INLINE void vp9_write_tree(vpx_writer *w, const vpx_tree_index *tree,
32                                   const vpx_prob *probs, int bits, int len,
33                                   vpx_tree_index i) {
34   do {
35     const int bit = (bits >> --len) & 1;
36     vpx_write(w, bit, probs[i >> 1]);
37     i = tree[i + bit];
38   } while (len);
39 }
40 
vp9_write_token(vpx_writer * w,const vpx_tree_index * tree,const vpx_prob * probs,const struct vp9_token * token)41 static INLINE void vp9_write_token(vpx_writer *w, const vpx_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_
52