vpx/vp9/common/vp9_treecoder.c
Dmitry Kovalev aea29cd278 General code cleanup inside treewriter-related files.
Change-Id: Ifaa40612a9c054d96112ba350c6f4adb46b1bd5b
2013-04-30 16:39:07 -07:00

79 lines
2.3 KiB
C

/*
* Copyright (c) 2010 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "vpx_config.h"
#if defined(CONFIG_DEBUG) && CONFIG_DEBUG
#include <assert.h>
#endif
#include "vp9/common/vp9_treecoder.h"
static void tree2tok(struct vp9_token *const p, vp9_tree t,
int i, int v, int l) {
v += v;
++l;
do {
const vp9_tree_index j = t[i++];
if (j <= 0) {
p[-j].value = v;
p[-j].len = l;
} else
tree2tok(p, t, j, v, l);
} while (++v & 1);
}
void vp9_tokens_from_tree(struct vp9_token *p, vp9_tree t) {
tree2tok(p, t, 0, 0, 0);
}
void vp9_tokens_from_tree_offset(struct vp9_token *p, vp9_tree t,
int offset) {
tree2tok(p - offset, t, 0, 0, 0);
}
static unsigned int convert_distribution(unsigned int i,
vp9_tree tree,
vp9_prob probs[],
unsigned int branch_ct[][2],
const unsigned int num_events[],
unsigned int tok0_offset) {
unsigned int left, right;
if (tree[i] <= 0) {
left = num_events[-tree[i] - tok0_offset];
} else {
left = convert_distribution(tree[i], tree, probs, branch_ct,
num_events, tok0_offset);
}
if (tree[i + 1] <= 0)
right = num_events[-tree[i + 1] - tok0_offset];
else
right = convert_distribution(tree[i + 1], tree, probs, branch_ct,
num_events, tok0_offset);
probs[i>>1] = get_binary_prob(left, right);
branch_ct[i>>1][0] = left;
branch_ct[i>>1][1] = right;
return left + right;
}
void vp9_tree_probs_from_distribution(
vp9_tree tree,
vp9_prob probs [ /* n-1 */ ],
unsigned int branch_ct [ /* n-1 */ ] [2],
const unsigned int num_events[ /* n */ ],
unsigned int tok0_offset) {
convert_distribution(0, tree, probs, branch_ct, num_events, tok0_offset);
}