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/encoder/vp9_treewriter.h" 12 13 static void tree2tok(struct vp9_token *tokens, const vpx_tree_index *tree, 14 int i, int v, int l) { 15 v += v; 16 ++l; 17 18 do { 19 const vpx_tree_index j = tree[i++]; 20 if (j <= 0) { 21 tokens[-j].value = v; 22 tokens[-j].len = l; 23 } else { 24 tree2tok(tokens, tree, j, v, l); 25 } 26 } while (++v & 1); 27 } 28 29 void vp9_tokens_from_tree(struct vp9_token *tokens, 30 const vpx_tree_index *tree) { 31 tree2tok(tokens, tree, 0, 0, 0); 32 } 33 34 static unsigned int convert_distribution(unsigned int i, vpx_tree tree, 35 unsigned int branch_ct[][2], 36 const unsigned int num_events[]) { 37 unsigned int left, right; 38 39 if (tree[i] <= 0) 40 left = num_events[-tree[i]]; 41 else 42 left = convert_distribution(tree[i], tree, branch_ct, num_events); 43 44 if (tree[i + 1] <= 0) 45 right = num_events[-tree[i + 1]]; 46 else 47 right = convert_distribution(tree[i + 1], tree, branch_ct, num_events); 48 49 branch_ct[i >> 1][0] = left; 50 branch_ct[i >> 1][1] = right; 51 return left + right; 52 } 53 54 void vp9_tree_probs_from_distribution(vpx_tree tree, 55 unsigned int branch_ct[/* n-1 */][2], 56 const unsigned int num_events[/* n */]) { 57 convert_distribution(0, tree, branch_ct, num_events); 58 } 59
