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 12 #include <assert.h> 13 14 #include "./vpx_config.h" 15 #include "vp9/common/vp9_treecoder.h" 16 17 static void tree2tok(struct vp9_token *const p, vp9_tree t, 18 int i, int v, int l) { 19 v += v; 20 ++l; 21 22 do { 23 const vp9_tree_index j = t[i++]; 24 25 if (j <= 0) { 26 p[-j].value = v; 27 p[-j].len = l; 28 } else { 29 tree2tok(p, t, j, v, l); 30 } 31 } while (++v & 1); 32 } 33 34 void vp9_tokens_from_tree(struct vp9_token *p, vp9_tree t) { 35 tree2tok(p, t, 0, 0, 0); 36 } 37 38 static unsigned int convert_distribution(unsigned int i, vp9_tree tree, 39 unsigned int branch_ct[][2], 40 const unsigned int num_events[]) { 41 unsigned int left, right; 42 43 if (tree[i] <= 0) 44 left = num_events[-tree[i]]; 45 else 46 left = convert_distribution(tree[i], tree, branch_ct, num_events); 47 48 if (tree[i + 1] <= 0) 49 right = num_events[-tree[i + 1]]; 50 else 51 right = convert_distribution(tree[i + 1], tree, branch_ct, num_events); 52 53 branch_ct[i >> 1][0] = left; 54 branch_ct[i >> 1][1] = right; 55 return left + right; 56 } 57 58 void vp9_tree_probs_from_distribution(vp9_tree tree, 59 unsigned int branch_ct[/* n-1 */][2], 60 const unsigned int num_events[/* n */]) { 61 convert_distribution(0, tree, branch_ct, num_events); 62 } 63 64 65
