michael@0: /*
michael@0:  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
michael@0:  *
michael@0:  *  Use of this source code is governed by a BSD-style license
michael@0:  *  that can be found in the LICENSE file in the root of the source
michael@0:  *  tree. An additional intellectual property rights grant can be found
michael@0:  *  in the file PATENTS.  All contributing project authors may
michael@0:  *  be found in the AUTHORS file in the root of the source tree.
michael@0:  */
michael@0: 
michael@0: 
michael@0: #include <assert.h>
michael@0: 
michael@0: #include "./vpx_config.h"
michael@0: #include "vp9/common/vp9_treecoder.h"
michael@0: 
michael@0: static void tree2tok(struct vp9_token *const p, vp9_tree t,
michael@0:                     int i, int v, int l) {
michael@0:   v += v;
michael@0:   ++l;
michael@0: 
michael@0:   do {
michael@0:     const vp9_tree_index j = t[i++];
michael@0: 
michael@0:     if (j <= 0) {
michael@0:       p[-j].value = v;
michael@0:       p[-j].len = l;
michael@0:     } else {
michael@0:       tree2tok(p, t, j, v, l);
michael@0:     }
michael@0:   } while (++v & 1);
michael@0: }
michael@0: 
michael@0: void vp9_tokens_from_tree(struct vp9_token *p, vp9_tree t) {
michael@0:   tree2tok(p, t, 0, 0, 0);
michael@0: }
michael@0: 
michael@0: static unsigned int convert_distribution(unsigned int i, vp9_tree tree,
michael@0:                                          unsigned int branch_ct[][2],
michael@0:                                          const unsigned int num_events[]) {
michael@0:   unsigned int left, right;
michael@0: 
michael@0:   if (tree[i] <= 0)
michael@0:     left = num_events[-tree[i]];
michael@0:   else
michael@0:     left = convert_distribution(tree[i], tree, branch_ct, num_events);
michael@0: 
michael@0:   if (tree[i + 1] <= 0)
michael@0:     right = num_events[-tree[i + 1]];
michael@0:   else
michael@0:     right = convert_distribution(tree[i + 1], tree, branch_ct, num_events);
michael@0: 
michael@0:   branch_ct[i >> 1][0] = left;
michael@0:   branch_ct[i >> 1][1] = right;
michael@0:   return left + right;
michael@0: }
michael@0: 
michael@0: void vp9_tree_probs_from_distribution(vp9_tree tree,
michael@0:                                       unsigned int branch_ct[/* n-1 */][2],
michael@0:                                       const unsigned int num_events[/* n */]) {
michael@0:   convert_distribution(0, tree, branch_ct, num_events);
michael@0: }
michael@0: 
michael@0: