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, 198 insertions, 0 deletions

diff --git a/third_party/aom/aom_dsp/prob.h b/third_party/aom/aom_dsp/prob.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 AOM_DSP_PROB_H_
+#define AOM_DSP_PROB_H_
+
+#include <assert.h>
+
+#include "./aom_config.h"
+#include "./aom_dsp_common.h"
+
+#include "aom_ports/bitops.h"
+#include "aom_ports/mem.h"
+
+#if CONFIG_DAALA_EC
+#include "aom_dsp/entcode.h"
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef uint8_t aom_prob;
+
+// TODO(negge): Rename this aom_prob once we remove vpxbool.
+typedef uint16_t aom_cdf_prob;
+
+#if CONFIG_EC_MULTISYMBOL
+#define CDF_SIZE(x) ((x) + 1)
+#endif
+
+#define CDF_PROB_BITS 15
+#define CDF_PROB_TOP (1 << CDF_PROB_BITS)
+
+#if CONFIG_DAALA_EC
+#define AOM_ICDF OD_ICDF
+#else
+#define AOM_ICDF(x) (x)
+#endif
+
+#define MAX_PROB 255
+
+#define aom_prob_half ((aom_prob)128)
+
+typedef int8_t aom_tree_index;
+
+#define TREE_SIZE(leaf_count) (-2 + 2 * (leaf_count))
+
+#define MODE_MV_COUNT_SAT 20
+
+/* We build coding trees compactly in arrays.
+   Each node of the tree is a pair of aom_tree_indices.
+   Array index often references a corresponding probability table.
+   Index <= 0 means done encoding/decoding and value = -Index,
+   Index > 0 means need another bit, specification at index.
+   Nonnegative indices are always even;  processing begins at node 0. */
+
+typedef const aom_tree_index aom_tree[];
+
+static INLINE aom_prob get_prob(unsigned int num, unsigned int den) {
+  assert(den != 0);
+  {
+    const int p = (int)(((uint64_t)num * 256 + (den >> 1)) / den);
+    // (p > 255) ? 255 : (p < 1) ? 1 : p;
+    const int clipped_prob = p | ((255 - p) >> 23) | (p == 0);
+    return (aom_prob)clipped_prob;
+  }
+}
+
+static INLINE aom_prob get_binary_prob(unsigned int n0, unsigned int n1) {
+  const unsigned int den = n0 + n1;
+  if (den == 0) return 128u;
+  return get_prob(n0, den);
+}
+
+/* This function assumes prob1 and prob2 are already within [1,255] range. */
+static INLINE aom_prob weighted_prob(int prob1, int prob2, int factor) {
+  return ROUND_POWER_OF_TWO(prob1 * (256 - factor) + prob2 * factor, 8);
+}
+
+static INLINE aom_prob merge_probs(aom_prob pre_prob, const unsigned int ct[2],
+                                   unsigned int count_sat,
+                                   unsigned int max_update_factor) {
+  const aom_prob prob = get_binary_prob(ct[0], ct[1]);
+  const unsigned int count = AOMMIN(ct[0] + ct[1], count_sat);
+  const unsigned int factor = max_update_factor * count / count_sat;
+  return weighted_prob(pre_prob, prob, factor);
+}
+
+// MODE_MV_MAX_UPDATE_FACTOR (128) * count / MODE_MV_COUNT_SAT;
+static const int count_to_update_factor[MODE_MV_COUNT_SAT + 1] = {
+  0,  6,  12, 19, 25, 32,  38,  44,  51,  57, 64,
+  70, 76, 83, 89, 96, 102, 108, 115, 121, 128
+};
+
+static INLINE aom_prob mode_mv_merge_probs(aom_prob pre_prob,
+                                           const unsigned int ct[2]) {
+  const unsigned int den = ct[0] + ct[1];
+  if (den == 0) {
+    return pre_prob;
+  } else {
+    const unsigned int count = AOMMIN(den, MODE_MV_COUNT_SAT);
+    const unsigned int factor = count_to_update_factor[count];
+    const aom_prob prob = get_prob(ct[0], den);
+    return weighted_prob(pre_prob, prob, factor);
+  }
+}
+
+void aom_tree_merge_probs(const aom_tree_index *tree, const aom_prob *pre_probs,
+                          const unsigned int *counts, aom_prob *probs);
+
+#if CONFIG_EC_MULTISYMBOL
+int tree_to_cdf(const aom_tree_index *tree, const aom_prob *probs,
+                aom_tree_index root, aom_cdf_prob *cdf, aom_tree_index *ind,
+                int *pth, int *len);
+
+static INLINE void av1_tree_to_cdf(const aom_tree_index *tree,
+                                   const aom_prob *probs, aom_cdf_prob *cdf) {
+  aom_tree_index index[16];
+  int path[16];
+  int dist[16];
+  tree_to_cdf(tree, probs, 0, cdf, index, path, dist);
+}
+
+#define av1_tree_to_cdf_1D(tree, probs, cdf, u) \
+  do {                                          \
+    int i;                                      \
+    for (i = 0; i < u; i++) {                   \
+      av1_tree_to_cdf(tree, probs[i], cdf[i]);  \
+    }                                           \
+  } while (0)
+
+#define av1_tree_to_cdf_2D(tree, probs, cdf, v, u)     \
+  do {                                                 \
+    int j;                                             \
+    int i;                                             \
+    for (j = 0; j < v; j++) {                          \
+      for (i = 0; i < u; i++) {                        \
+        av1_tree_to_cdf(tree, probs[j][i], cdf[j][i]); \
+      }                                                \
+    }                                                  \
+  } while (0)
+
+void av1_indices_from_tree(int *ind, int *inv, const aom_tree_index *tree);
+#endif
+
+DECLARE_ALIGNED(16, extern const uint8_t, aom_norm[256]);
+
+#if CONFIG_EC_ADAPT
+static INLINE void update_cdf(aom_cdf_prob *cdf, int val, int nsymbs) {
+  const int rate = 4 + (cdf[nsymbs] > 31) + get_msb(nsymbs);
+  const int rate2 = 5;
+  int i, tmp;
+  int diff;
+#if 1
+  const int tmp0 = 1 << rate2;
+  tmp = AOM_ICDF(tmp0);
+  diff = ((CDF_PROB_TOP - (nsymbs << rate2)) >> rate) << rate;
+// Single loop (faster)
+#if CONFIG_DAALA_EC && CONFIG_EC_SMALLMUL
+  for (i = 0; i < nsymbs - 1; ++i, tmp -= tmp0) {
+    tmp -= (i == val ? diff : 0);
+    cdf[i] += ((tmp - cdf[i]) >> rate);
+  }
+#else
+  for (i = 0; i < nsymbs - 1; ++i, tmp += tmp0) {
+    tmp += (i == val ? diff : 0);
+    cdf[i] -= ((cdf[i] - tmp) >> rate);
+  }
+#endif
+#else
+  for (i = 0; i < nsymbs; ++i) {
+    tmp = (i + 1) << rate2;
+    cdf[i] -= ((cdf[i] - tmp) >> rate);
+  }
+  diff = CDF_PROB_TOP - cdf[nsymbs - 1];
+
+  for (i = val; i < nsymbs; ++i) {
+    cdf[i] += diff;
+  }
+#endif
+  cdf[nsymbs] += (cdf[nsymbs] < 32);
+}
+#endif
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
+#endif  // AOM_DSP_PROB_H_