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authorJohn Koleszar <jkoleszar@google.com>2012-11-27 13:59:17 -0800
committerJohn Koleszar <jkoleszar@google.com>2012-11-27 14:12:30 -0800
commitfcccbcbb395ce4cf31b54ce1245cc28e5e3ef4c1 (patch)
tree68e128e48e3f5ab1de1c163fa3a12ea47f5d8d51 /vp9/common/vp9_treecoder.c
parent3bf7b131c8ebb6b4d63a8b70d69066dcbc4ed896 (diff)
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Add vp9_ prefix to all vp9 files
Support for gyp which doesn't support multiple objects in the same static library having the same basename. Change-Id: Ib947eefbaf68f8b177a796d23f875ccdfa6bc9dc
Diffstat (limited to 'vp9/common/vp9_treecoder.c')
-rw-r--r--vp9/common/vp9_treecoder.c138
1 files changed, 138 insertions, 0 deletions
diff --git a/vp9/common/vp9_treecoder.c b/vp9/common/vp9_treecoder.c
new file mode 100644
index 000000000..096dd59e5
--- /dev/null
+++ b/vp9/common/vp9_treecoder.c
@@ -0,0 +1,138 @@
+/*
+ * 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 <stdio.h>
+
+#include "vp9_treecoder.h"
+
+static void tree2tok(
+ struct vp9_token_struct *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_struct *p, vp9_tree t) {
+ tree2tok(p, t, 0, 0, 0);
+}
+
+void vp9_tokens_from_tree_offset(struct vp9_token_struct *p, vp9_tree t,
+ int offset) {
+ tree2tok(p - offset, t, 0, 0, 0);
+}
+
+static void branch_counts(
+ int n, /* n = size of alphabet */
+ vp9_token tok [ /* n */ ],
+ vp9_tree tree,
+ unsigned int branch_ct [ /* n-1 */ ] [2],
+ const unsigned int num_events[ /* n */ ]
+) {
+ const int tree_len = n - 1;
+ int t = 0;
+
+#if CONFIG_DEBUG
+ assert(tree_len);
+#endif
+
+ do {
+ branch_ct[t][0] = branch_ct[t][1] = 0;
+ } while (++t < tree_len);
+
+ t = 0;
+
+ do {
+ int L = tok[t].Len;
+ const int enc = tok[t].value;
+ const unsigned int ct = num_events[t];
+
+ vp9_tree_index i = 0;
+
+ do {
+ const int b = (enc >> --L) & 1;
+ const int j = i >> 1;
+#if CONFIG_DEBUG
+ assert(j < tree_len && 0 <= L);
+#endif
+
+ branch_ct [j] [b] += ct;
+ i = tree[ i + b];
+ } while (i > 0);
+
+#if CONFIG_DEBUG
+ assert(!L);
+#endif
+ } while (++t < n);
+
+}
+
+
+void vp9_tree_probs_from_distribution(
+ int n, /* n = size of alphabet */
+ vp9_token tok [ /* n */ ],
+ vp9_tree tree,
+ vp9_prob probs [ /* n-1 */ ],
+ unsigned int branch_ct [ /* n-1 */ ] [2],
+ const unsigned int num_events[ /* n */ ],
+ unsigned int Pfac,
+ int rd
+) {
+ const int tree_len = n - 1;
+ int t = 0;
+
+ branch_counts(n, tok, tree, branch_ct, num_events);
+
+ do {
+ const unsigned int *const c = branch_ct[t];
+ const unsigned int tot = c[0] + c[1];
+
+#if CONFIG_DEBUG
+ assert(tot < (1 << 24)); /* no overflow below */
+#endif
+
+ if (tot) {
+ const unsigned int p = ((c[0] * Pfac) + (rd ? tot >> 1 : 0)) / tot;
+ probs[t] = p < 256 ? (p ? p : 1) : 255; /* agree w/old version for now */
+ } else
+ probs[t] = vp9_prob_half;
+ } while (++t < tree_len);
+}
+
+vp9_prob vp9_bin_prob_from_distribution(const unsigned int counts[2]) {
+ int tot_count = counts[0] + counts[1];
+ vp9_prob prob;
+ if (tot_count) {
+ prob = (counts[0] * 255 + (tot_count >> 1)) / tot_count;
+ prob += !prob;
+ } else {
+ prob = 128;
+ }
+ return prob;
+}