/usr/include/tesseract/intfeaturedist.h is in libtesseract-dev 3.02.01-6.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 | // Copyright 2011 Google Inc. All Rights Reserved.
// Author: rays@google.com (Ray Smith)
///////////////////////////////////////////////////////////////////////
// File: intfeaturedist.h
// Description: Fast set-difference-based feature distance calculator.
// Created: Thu Sep 01 12:14:30 PDT 2011
//
// 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_CLASSIFY_INTFEATUREDIST_H_
#define TESSERACT_CLASSIFY_INTFEATUREDIST_H_
#include "genericvector.h"
namespace tesseract {
class IntFeatureMap;
// Feature distance calculator designed to provide a fast distance calculation
// based on set difference between a given feature set and many other feature
// sets in turn.
// Representation of a feature set as an array of bools that are sparsely
// true, and companion arrays that allow fast feature set distance
// calculations with allowance of offsets in position.
// Init is expensive, so for greatest efficiency, to re-initialize for a new
// feature set, use Set(..., false) on the SAME feature set as was used to
// setup with Set(..., true), to return to its initialized state before
// reuse with Set(..., true) on a new feature set.
class IntFeatureDist {
public:
IntFeatureDist();
~IntFeatureDist();
// Initialize the bool array to the given size of feature space.
// The feature_map is just borrowed, and must exist for the entire
// lifetime of the IntFeatureDist.
void Init(const IntFeatureMap* feature_map);
// Setup the map for the given indexed_features that have been indexed by
// feature_map. After use, use Set(..., false) to reset to the initial state
// as this is faster than calling Init for sparse spaces.
void Set(const GenericVector<int>& indexed_features,
int canonical_count, bool value);
// Compute the distance between the given feature vector and the last
// Set feature vector.
double FeatureDistance(const GenericVector<int>& features) const;
double DebugFeatureDistance(const GenericVector<int>& features) const;
private:
// Clear all data.
void Clear();
// Size of the indexed feature space.
int size_;
// Total weight of features currently stored in the maps.
double total_feature_weight_;
// Pointer to IntFeatureMap given at Init to find offset features.
const IntFeatureMap* feature_map_;
// Array of bools indicating presence of a feature.
bool* features_;
// Array indicating the presence of a feature offset by one unit.
bool* features_delta_one_;
// Array indicating the presence of a feature offset by two units.
bool* features_delta_two_;
};
} // namespace tesseract
#endif // TESSERACT_CLASSIFY_INTFEATUREDIST_H_
|