pupil_localization.h

#ifndef INCLUDE_GAZE_PIPELINE_STEPS_PUPIL_LOCALIZATION_H_
#define INCLUDE_GAZE_PIPELINE_STEPS_PUPIL_LOCALIZATION_H_

#include <vector>

#include "dlib/matrix.h"

#include "gaze/gui/visualizeable.h"
#include "gaze/pipeline_step.h"
#include "gaze/util/data.h"


namespace gaze {

namespace util {

void fill_displacement_tables(dlib::matrix<double>& table_x,  // NOLINT
                              dlib::matrix<double>& table_y,  // NOLINT
                              int size);

template <typename T>
void normalize_and_threshold_gradients(
    dlib::matrix<T>& horizontal,  // NOLINT
    dlib::matrix<T>& vertical,  // NOLINT
    double relative_threshold = -1) {
  dlib::matrix<T> magnitude;
  magnitude = dlib::sqrt(dlib::squared(horizontal) +
                         dlib::squared(vertical));

  // Thresholding
  if (relative_threshold >= 0) {
    T threshold = dlib::mean(magnitude)
                + dlib::stddev(magnitude) * relative_threshold;
    for (int row = 0; row < horizontal.nr(); ++row) {
      for (int col = 0; col < horizontal.nc(); ++col) {
        if (magnitude(row, col) < threshold) {
          horizontal(row, col) = 0;
          vertical(row, col) = 0;
        }
      }
    }
  }

  // Normalization
  horizontal = dlib::pointwise_multiply(
      horizontal, dlib::reciprocal(magnitude));
  vertical = dlib::pointwise_multiply(
      vertical, dlib::reciprocal(magnitude));
}

}  // namespace util

namespace pipeline {

class PupilLocalization final
    : public PipelineStep,
      public gui::ImageVisualizeable {
  dlib::matrix<double> displacement_table_x;
  dlib::matrix<double> displacement_table_y;
  double relative_threshold_factor;
  double sigma;

 public:
    PupilLocalization();

    void process(util::Data& data) override;

    void visualize(util::Data& data) override;
};

}  // namespace pipeline

}  // namespace gaze

#endif  // INCLUDE_GAZE_PIPELINE_STEPS_PUPIL_LOCALIZATION_H_