RotateLayer.h

/* Copyright (c) 2016 Baidu, Inc. All Rights Reserve.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License. */

#pragma once

#include "Layer.h"
#include "paddle/math/Matrix.h"

namespace paddle {
/**
 * A layer for rotating a multi-channel feature map (M x N x C) in the spatial
 * domain
 * The rotation is 90 degrees in clock-wise for each channel
 * \f[
 *   y(j,i,:) = x(M-i-1,j,:)
 * \f]
 * where \f$x\f$ is (M x N x C) input, and \f$y\f$ is (N x M x C) output.
 *
 * The config file api is rotate_layer
 *
 */

class RotateLayer : public Layer {
public:
  explicit RotateLayer(const LayerConfig& config) : Layer(config) {}

  bool init(const LayerMap& layerMap, const ParameterMap& parameterMap);

  void forward(PassType passType);
  void backward(const UpdateCallback& callback = nullptr);

private:
  int batchSize_;
  int size_;
  int height_;
  int width_;
  int channels_;
};

}  // namespace paddle