AveragePooling.h

// Copyright 2016-present, Facebook, Inc.
// All rights reserved.
//
// This source code is licensed under the license found in the
// LICENSE file in the root directory of this source tree.

#ifndef CPU_AVERAGEPOOLING_H
#define CPU_AVERAGEPOOLING_H


template <typename T>
void AveragePooling_ForwardPass(T *input_features, T *output_features,
                                Int nPlanes, Int input_stride,
                                Int output_stride, Int *rules, Int nHot,
                                Int filterVolume) {
  for (Int outSite = 0; outSite < nHot; outSite++) {
    Int i = rules[2 * outSite] * input_stride;
    Int o = rules[2 * outSite + 1] * output_stride;
    for (Int plane = 0; plane < nPlanes; plane++)
      output_features[o + plane] += input_features[i + plane] / filterVolume;
  }
}
template <typename T>
void AveragePooling_BackwardPass(T *d_input_features, T *d_output_features,
                                 Int nPlanes, Int input_stride,
                                 Int output_stride, Int *rules, Int nHot,
                                 Int filterVolume) {
  for (Int outSite = 0; outSite < nHot; outSite++) {
    Int i = rules[2 * outSite] * input_stride;
    Int o = rules[2 * outSite + 1] * output_stride;
    for (Int plane = 0; plane < nPlanes; plane++)
      d_input_features[i + plane] +=
          d_output_features[o + plane] / filterVolume;
  }
}
#endif /* CPU_AVERAGEPOOLING_H */