Import aom library

This is the reference implementation for the Alliance for Open Media's av1 video code.

The commit used was 4d668d7feb1f8abd809d1bca0418570a7f142a36.

1 files changed, 96 insertions, 0 deletions

diff --git a/third_party/aom/av1/encoder/variance_tree.h b/third_party/aom/av1/encoder/variance_tree.h
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+++ b/third_party/aom/av1/encoder/variance_tree.h
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+/*
+ * Copyright (c) 2016, Alliance for Open Media. All rights reserved
+ *
+ * This source code is subject to the terms of the BSD 2 Clause License and
+ * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
+ * was not distributed with this source code in the LICENSE file, you can
+ * obtain it at www.aomedia.org/license/software. If the Alliance for Open
+ * Media Patent License 1.0 was not distributed with this source code in the
+ * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
+ */
+
+#ifndef AV1_ENCODER_VARIANCE_TREE_H_
+#define AV1_ENCODER_VARIANCE_TREE_H_
+
+#include <assert.h>
+
+#include "./aom_config.h"
+
+#include "aom/aom_integer.h"
+
+#include "av1/common/enums.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct AV1Common;
+struct ThreadData;
+
+typedef struct {
+  int64_t sum_square_error;
+  int64_t sum_error;
+  int log2_count;
+  int variance;
+} VAR;
+
+typedef struct {
+  VAR none;
+  VAR horz[2];
+  VAR vert[2];
+} partition_variance;
+
+typedef struct VAR_TREE {
+  int force_split;
+  partition_variance variances;
+  struct VAR_TREE *split[4];
+  BLOCK_SIZE bsize;
+  const uint8_t *src;
+  const uint8_t *ref;
+  int src_stride;
+  int ref_stride;
+  int width;
+  int height;
+#if CONFIG_HIGHBITDEPTH
+  int highbd;
+#endif  // CONFIG_HIGHBITDEPTH
+} VAR_TREE;
+
+void av1_setup_var_tree(struct AV1Common *cm, struct ThreadData *td);
+void av1_free_var_tree(struct ThreadData *td);
+
+// Set variance values given sum square error, sum error, count.
+static INLINE void fill_variance(int64_t s2, int64_t s, int c, VAR *v) {
+  v->sum_square_error = s2;
+  v->sum_error = s;
+  v->log2_count = c;
+  v->variance =
+      (int)(256 * (v->sum_square_error -
+                   ((v->sum_error * v->sum_error) >> v->log2_count)) >>
+            v->log2_count);
+}
+
+static INLINE void sum_2_variances(const VAR *a, const VAR *b, VAR *r) {
+  assert(a->log2_count == b->log2_count);
+  fill_variance(a->sum_square_error + b->sum_square_error,
+                a->sum_error + b->sum_error, a->log2_count + 1, r);
+}
+
+static INLINE void fill_variance_node(VAR_TREE *vt) {
+  sum_2_variances(&vt->split[0]->variances.none, &vt->split[1]->variances.none,
+                  &vt->variances.horz[0]);
+  sum_2_variances(&vt->split[2]->variances.none, &vt->split[3]->variances.none,
+                  &vt->variances.horz[1]);
+  sum_2_variances(&vt->split[0]->variances.none, &vt->split[2]->variances.none,
+                  &vt->variances.vert[0]);
+  sum_2_variances(&vt->split[1]->variances.none, &vt->split[3]->variances.none,
+                  &vt->variances.vert[1]);
+  sum_2_variances(&vt->variances.vert[0], &vt->variances.vert[1],
+                  &vt->variances.none);
+}
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
+#endif /* AV1_ENCODER_VARIANCE_TREE_H_ */