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+///////////////////////////////////////////////////////////////////////
+// File:        maxpool.h
+// Description: Standard Max-Pooling layer.
+// Author:      Ray Smith
+// Created:     Tue Mar 18 16:28:18 PST 2014
+//
+// (C) Copyright 2014, Google Inc.
+// 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.
+///////////////////////////////////////////////////////////////////////
+
+#ifndef TESSERACT_LSTM_MAXPOOL_H_
+#define TESSERACT_LSTM_MAXPOOL_H_
+
+#include "reconfig.h"
+
+namespace tesseract {
+
+// Maxpooling reduction. Independently for each input, selects the location
+// in the rectangle that contains the max value.
+// Backprop propagates only to the position that was the max.
+class Maxpool : public Reconfig {
+ public:
+  TESS_API
+  Maxpool(const char* name, int ni, int x_scale, int y_scale);
+  ~Maxpool() override = default;
+
+  // Accessors.
+  STRING spec() const override {
+    STRING spec;
+    spec.add_str_int("Mp", y_scale_);
+    spec.add_str_int(",", x_scale_);
+    return spec;
+  }
+
+  // Reads from the given file. Returns false in case of error.
+  bool DeSerialize(TFile* fp) override;
+
+  // Runs forward propagation of activations on the input line.
+  // See Network for a detailed discussion of the arguments.
+  void Forward(bool debug, const NetworkIO& input,
+               const TransposedArray* input_transpose,
+               NetworkScratch* scratch, NetworkIO* output) override;
+
+  // Runs backward propagation of errors on the deltas line.
+  // See Network for a detailed discussion of the arguments.
+  bool Backward(bool debug, const NetworkIO& fwd_deltas,
+                NetworkScratch* scratch,
+                NetworkIO* back_deltas) override;
+
+ private:
+  // Memory of which input was the max.
+  GENERIC_2D_ARRAY<int> maxes_;
+};
+
+
+}  // namespace tesseract.
+
+
+
+
+
+#endif  // TESSERACT_LSTM_MAXPOOL_H_