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diff --git a/third_party/aom/av1/encoder/ml.c b/third_party/aom/av1/encoder/ml.c
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+++ b/third_party/aom/av1/encoder/ml.c
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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.
+ */
+
+#include <assert.h>
+#include <math.h>
+
+#include "aom_dsp/aom_dsp_common.h"
+#include "aom_dsp/mathutils.h"
+#include "av1/encoder/ml.h"
+
+void av1_nn_output_prec_reduce(float *const output, int num_output) {
+  const int prec_bits = 9;
+  const int prec = 1 << prec_bits;
+  const float inv_prec = (float)(1.0 / prec);
+  for (int i = 0; i < num_output; i++) {
+    output[i] = ((int)(output[i] * prec + 0.5)) * inv_prec;
+  }
+}
+
+// Calculate prediction based on the given input features and neural net config.
+// Assume there are no more than NN_MAX_NODES_PER_LAYER nodes in each hidden
+// layer.
+void av1_nn_predict_c(const float *input_nodes,
+                      const NN_CONFIG *const nn_config, int reduce_prec,
+                      float *const output) {
+  int num_input_nodes = nn_config->num_inputs;
+  int buf_index = 0;
+  float buf[2][NN_MAX_NODES_PER_LAYER];
+
+  // Propagate hidden layers.
+  const int num_layers = nn_config->num_hidden_layers;
+  assert(num_layers <= NN_MAX_HIDDEN_LAYERS);
+  for (int layer = 0; layer < num_layers; ++layer) {
+    const float *layer_weights = nn_config->weights[layer];
+    const float *layer_bias = nn_config->bias[layer];
+    float *output_nodes = buf[buf_index];
+    const int num_output_nodes = nn_config->num_hidden_nodes[layer];
+    assert(num_output_nodes < NN_MAX_NODES_PER_LAYER);
+    for (int node = 0; node < num_output_nodes; ++node) {
+      float val = layer_bias[node];
+      for (int i = 0; i < num_input_nodes; ++i)
+        val += layer_weights[node * num_input_nodes + i] * input_nodes[i];
+      // ReLU as activation function.
+      val = val > 0.0f ? val : 0.0f;  // Could use AOMMAX().
+      output_nodes[node] = val;
+    }
+    num_input_nodes = num_output_nodes;
+    input_nodes = output_nodes;
+    buf_index = 1 - buf_index;
+  }
+
+  // Final output layer.
+  const float *layer_weights = nn_config->weights[num_layers];
+  const float *layer_bias = nn_config->bias[num_layers];
+  for (int node = 0; node < nn_config->num_outputs; ++node) {
+    float val = layer_bias[node];
+    for (int i = 0; i < num_input_nodes; ++i)
+      val += layer_weights[node * num_input_nodes + i] * input_nodes[i];
+    output[node] = val;
+  }
+  if (reduce_prec) av1_nn_output_prec_reduce(output, nn_config->num_outputs);
+}
+
+#if CONFIG_NN_V2
+// Applies the ReLu activation to one fc layer
+// output[i] = Max(input[i],0.0f)
+static float *nn_relu(const float *input, FC_LAYER *layer) {
+  for (int i = 0; i < layer->num_outputs; ++i) {
+    layer->output[i] = AOMMAX(input[i], 0.0f);
+  }
+
+  return layer->output;
+}
+
+// Applies the Sigmoid activation to one fc layer
+// output[i] = 1/(1+exp(input[i]))
+static float *nn_sigmoid(const float *input, FC_LAYER *layer) {
+  for (int i = 0; i < layer->num_outputs; ++i) {
+    const float tmp = AOMMIN(AOMMAX(input[i], -10.0f), 10.0f);
+    layer->output[i] = 1.0f / (1.0f + expf(-tmp));
+  }
+
+  return layer->output;
+}
+
+// Forward prediction in one fc layer, used in function av1_nn_predict_V2
+static float *nn_fc_forward(const float *input, FC_LAYER *layer) {
+  const float *weights = layer->weights;
+  const float *bias = layer->bias;
+  assert(layer->num_outputs < NN_MAX_NODES_PER_LAYER);
+  // fc
+  for (int node = 0; node < layer->num_outputs; ++node) {
+    float val = bias[node];
+    for (int i = 0; i < layer->num_inputs; ++i) val += weights[i] * input[i];
+    layer->output[node] = val;
+    weights += layer->num_inputs;
+  }
+
+  // activation
+  switch (layer->activation) {
+    case NONE: return layer->output;
+    case RELU: return nn_relu(layer->output, layer);
+    case SIGMOID: return nn_sigmoid(layer->output, layer);
+    case SOFTSIGN:
+      assert(0 && "Softsign has not been supported in NN.");  // TO DO
+      return NULL;
+    default:
+      assert(0 && "Unknown activation");  // Unknown activation
+      return NULL;
+  }
+}
+
+void av1_nn_predict_v2(const float *feature, NN_CONFIG_V2 *nn_config,
+                       int reduce_prec, float *output) {
+  const float *input_nodes = feature;
+
+  // Propagate the layers.
+  const int num_layers = nn_config->num_hidden_layers;
+  assert(num_layers <= NN_MAX_HIDDEN_LAYERS);
+  for (int i = 0; i < num_layers; ++i) {
+    input_nodes = nn_fc_forward(input_nodes, nn_config->layer + i);
+    assert(nn_config->layer[i + 1].num_inputs ==
+           nn_config->layer[i].num_outputs);
+  }
+
+  // Final layer
+  input_nodes = nn_fc_forward(input_nodes, nn_config->layer + num_layers);
+  assert(nn_config->layer[num_layers].num_outputs == nn_config->num_logits);
+  // Copy the final layer output
+  memcpy(output, input_nodes, sizeof(*input_nodes) * nn_config->num_logits);
+  if (reduce_prec) av1_nn_output_prec_reduce(output, nn_config->num_logits);
+}
+#endif  // CONFIG_NN_V2
+
+void av1_nn_softmax(const float *input, float *output, int n) {
+  // Softmax function is invariant to adding the same constant
+  // to all input values, so we subtract the maximum input to avoid
+  // possible overflow.
+  float max_input = input[0];
+  for (int i = 1; i < n; i++) max_input = AOMMAX(max_input, input[i]);
+  float sum_out = 0.0f;
+  for (int i = 0; i < n; i++) {
+    // Clamp to range [-10.0, 0.0] to prevent FE_UNDERFLOW errors.
+    const float normalized_input = AOMMAX(input[i] - max_input, -10.0f);
+    output[i] = expf(normalized_input);
+    sum_out += output[i];
+  }
+  for (int i = 0; i < n; i++) output[i] /= sum_out;
+}
+
+void av1_nn_fast_softmax_16_c(const float *input, float *output) {
+  const int kNumClasses = 16;
+  float max_input = input[0];
+  for (int i = 1; i < kNumClasses; i++) max_input = AOMMAX(max_input, input[i]);
+  float sum_out = 0.0f;
+  for (int i = 0; i < kNumClasses; i++) {
+    // Clamp to range [-10.0, 0.0] to prevent FE_UNDERFLOW errors.
+    const float normalized_input = AOMMAX(input[i] - max_input, -10.0f);
+    output[i] = approx_exp(normalized_input);
+    sum_out += output[i];
+  }
+  for (int i = 0; i < kNumClasses; i++) output[i] /= sum_out;
+}