kl_loss_layer.hpp

#ifndef CAFFE_KL_LOSS_LAYER_HPP_
#define CAFFE_KL_LOSS_LAYER_HPP_

#include <vector>
#include "caffe/blob.hpp"
#include "caffe/common.hpp"
#include "caffe/layer.hpp"
#include "caffe/proto/caffe.pb.h"
#include "caffe/layers/loss_layer.hpp"

namespace caffe {

template <typename Dtype>
class KlLossLayer : public LossLayer<Dtype> {
 public:
  explicit KlLossLayer(const LayerParameter& param)
      : LossLayer<Dtype>(param) {}
  virtual void LayerSetUp(const vector<Blob<Dtype>*>& bottom,
      const vector<Blob<Dtype>*>& top);
  virtual void Reshape(const vector<Blob<Dtype>*>& bottom,
      const vector<Blob<Dtype>*>& top);

  virtual inline const char* type() const { return "KlLoss"; }

  virtual inline int ExactNumBottomBlobs() const { return -1; }
  virtual inline int MinBottomBlobs() const {return 3; }
  virtual inline int MaxBottomBlobs() const {return 4; }
  virtual inline int ExactNumTopBlobs() const {return -1; }
  virtual inline int MinTopBlobs() const {return 1; }
  virtual inline int MaxTopBlobs() const {return 2; }
  virtual inline bool AllowForceBackward(const int bottom_index) const { return true; }


 protected:
  virtual void Forward_cpu(const vector<Blob<Dtype>*>& bottom,
      const vector<Blob<Dtype>*>& top);
  virtual void Forward_gpu(const vector<Blob<Dtype>*>& bottom,
      const vector<Blob<Dtype>*>& top);

  virtual void Backward_cpu(const vector<Blob<Dtype>*>& top,
      const vector<bool>& propagate_down, const vector<Blob<Dtype>*>& bottom);
  virtual void Backward_gpu(const vector<Blob<Dtype>*>& top,
      const vector<bool>& propagate_down, const vector<Blob<Dtype>*>& bottom);

  Blob<Dtype> diff_;
  Blob<Dtype> error_;
  Blob<Dtype> ones_;
  Dtype normalize_divider_;
  bool has_weights_;
};

}  // namespace caffe

#endif  // CAFFE_KL_LOSS_LAYER_HPP_