dlib C++ Library - setup_hashed_features.h

// Copyright (C) 2011 Davis E. King (davis@dlib.net)
// License: Boost Software License See LICENSE.txt for the full license.
#ifndef DLIB_SETUP_HAShED_FEATURES_Hh_
#define DLIB_SETUP_HAShED_FEATURES_Hh_
#include "setup_hashed_features_abstract.h"
#include "scan_image_pyramid.h"
#include "scan_image_boxes.h"
#include "../lsh.h"
#include "../statistics.h"
#include "../image_keypoint.h"
#include "../geometry.h"
namespace dlib
{
// ----------------------------------------------------------------------------------------
 class image_hash_construction_failure : public error
 {
 public:
 image_hash_construction_failure(
 const std::string& a
 ): error(a) {}
 };
// ----------------------------------------------------------------------------------------
 template <
 typename image_scanner
 >
 void use_uniform_feature_weights (
 image_scanner& scanner
 )
 {
 typename image_scanner::feature_extractor_type fe;
 fe.copy_configuration(scanner.get_feature_extractor());
 fe.use_uniform_feature_weights();
 scanner.copy_configuration(fe);
 }
// ----------------------------------------------------------------------------------------
 template <
 typename image_scanner
 >
 void use_relative_feature_weights (
 image_scanner& scanner
 )
 {
 typename image_scanner::feature_extractor_type fe;
 fe.copy_configuration(scanner.get_feature_extractor());
 fe.use_relative_feature_weights();
 scanner.copy_configuration(fe);
 }
// ----------------------------------------------------------------------------------------
// ----------------------------------------------------------------------------------------
// stuff for scan_image_pyramid
// ----------------------------------------------------------------------------------------
// ----------------------------------------------------------------------------------------
 template <
 typename image_array,
 typename pyramid,
 typename feature_extractor,
 template <typename fe, typename hash> class feature_image
 >
 void setup_hashed_features (
 scan_image_pyramid<pyramid, feature_image<feature_extractor, projection_hash> >& scanner,
 const image_array& images,
 const feature_extractor& fe,
 int bits,
 unsigned long num_samples = 200000
 )
 {
 // make sure requires clause is not broken
 DLIB_ASSERT(0 < bits && bits <= 32 &&
 num_samples > 1 && 
 images.size() > 0,
 "\t void setup_hashed_features()"
 << "\n\t Invalid inputs were given to this function. "
 << "\n\t bits: " << bits 
 << "\n\t num_samples: " << num_samples 
 << "\n\t images.size(): " << images.size() 
 );
 pyramid pyr;
 const random_subset_selector<typename feature_extractor::descriptor_type>& samps = 
 randomly_sample_image_features(images, pyr, fe, num_samples);
 if (samps.size() <= 1)
 throw dlib::image_hash_construction_failure("Images too small, not able to gather enough samples to make hash");
 projection_hash phash = create_random_projection_hash(samps, bits);
 feature_image<feature_extractor, projection_hash> hfe;
 hfe.copy_configuration(scanner.get_feature_extractor());
 hfe.set_hash(phash);
 hfe.copy_configuration(fe);
 scanner.copy_configuration(hfe);
 }
// ----------------------------------------------------------------------------------------
 template <
 typename image_array,
 typename pyramid,
 typename feature_extractor,
 template <typename fe, typename hash> class feature_image
 >
 void setup_hashed_features (
 scan_image_pyramid<pyramid, feature_image<feature_extractor, projection_hash> >& scanner,
 const image_array& images,
 int bits,
 unsigned long num_samples = 200000
 )
 {
 // make sure requires clause is not broken
 DLIB_ASSERT(0 < bits && bits <= 32 &&
 num_samples > 1 && 
 images.size() > 0,
 "\t void setup_hashed_features()"
 << "\n\t Invalid inputs were given to this function. "
 << "\n\t bits: " << bits 
 << "\n\t num_samples: " << num_samples 
 << "\n\t images.size(): " << images.size() 
 );
 feature_extractor fe;
 setup_hashed_features(scanner, images, fe, bits, num_samples);
 }
// ----------------------------------------------------------------------------------------
// ----------------------------------------------------------------------------------------
// stuff for scan_image_boxes
// ----------------------------------------------------------------------------------------
// ----------------------------------------------------------------------------------------
 template <
 typename image_array,
 typename feature_extractor,
 template <typename fe, typename hash> class feature_image,
 typename box_generator
 >
 void setup_hashed_features (
 scan_image_boxes<feature_image<feature_extractor, projection_hash>,box_generator >& scanner,
 const image_array& images,
 const feature_extractor& fe,
 int bits,
 unsigned long num_samples = 200000
 )
 {
 // make sure requires clause is not broken
 DLIB_ASSERT(0 < bits && bits <= 32 &&
 num_samples > 1 && 
 images.size() > 0,
 "\t void setup_hashed_features()"
 << "\n\t Invalid inputs were given to this function. "
 << "\n\t bits: " << bits 
 << "\n\t num_samples: " << num_samples 
 << "\n\t images.size(): " << images.size() 
 );
 pyramid_disable pyr;
 const random_subset_selector<typename feature_extractor::descriptor_type>& samps = 
 randomly_sample_image_features(images, pyr, fe, num_samples);
 if (samps.size() <= 1)
 throw dlib::image_hash_construction_failure("Images too small, not able to gather enough samples to make hash");
 projection_hash phash = create_random_projection_hash(samps, bits);
 feature_image<feature_extractor, projection_hash> hfe;
 hfe.copy_configuration(scanner.get_feature_extractor());
 hfe.set_hash(phash);
 hfe.copy_configuration(fe);
 scanner.copy_configuration(hfe);
 }
// ----------------------------------------------------------------------------------------
 template <
 typename image_array,
 typename feature_extractor,
 template <typename fe, typename hash> class feature_image,
 typename box_generator
 >
 void setup_hashed_features (
 scan_image_boxes<feature_image<feature_extractor, projection_hash>,box_generator>& scanner,
 const image_array& images,
 int bits,
 unsigned long num_samples = 200000
 )
 {
 // make sure requires clause is not broken
 DLIB_ASSERT(0 < bits && bits <= 32 &&
 num_samples > 1 && 
 images.size() > 0,
 "\t void setup_hashed_features()"
 << "\n\t Invalid inputs were given to this function. "
 << "\n\t bits: " << bits 
 << "\n\t num_samples: " << num_samples 
 << "\n\t images.size(): " << images.size() 
 );
 feature_extractor fe;
 setup_hashed_features(scanner, images, fe, bits, num_samples);
 }
// ----------------------------------------------------------------------------------------
}
#endif // DLIB_SETUP_HAShED_FEATURES_Hh_