Face recognition with Dlib

CMakeLists.txt

cmake_minimum_required(VERSION 3.0.0)
project(face_detection VERSION 0.0.1)
set(CMAKE_CXX_STANDARD 17)

set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)

include(FetchContent)
FetchContent_Declare(dlib
  GIT_REPOSITORY https://github.com/davisking/dlib.git
  GIT_TAG        v19.24
)
FetchContent_MakeAvailable(dlib)

add_executable(face_detection main.cpp dnn_face_recognition_model.h)
target_link_libraries(face_detection dlib::dlib)

dnn_face_recognition_model.h

#ifndef FACE_DETECTION_DNN_FACE_RECOGNITION_MODEL_H
#define FACE_DETECTION_DNN_FACE_RECOGNITION_MODEL_H

#include <dlib/dnn.h>
#include <dlib/clustering.h>

template <template <int,template<typename>class,int,typename> class block, int N, template<typename>class BN, typename SUBNET>
using residual = dlib::add_prev1<block<N,BN,1,dlib::tag1<SUBNET>>>;

template <template <int,template<typename>class,int,typename> class block, int N, template<typename>class BN, typename SUBNET>
using residual_down = dlib::add_prev2<dlib::avg_pool<2,2,2,2,dlib::skip1<dlib::tag2<block<N,BN,2,dlib::tag1<SUBNET>>>>>>;

template <int N, template <typename> class BN, int stride, typename SUBNET>
using block  = BN<dlib::con<N,3,3,1,1,dlib::relu<BN<dlib::con<N,3,3,stride,stride,SUBNET>>>>>;

template <int N, typename SUBNET> using ares      = dlib::relu<residual<block,N,dlib::affine,SUBNET>>;
template <int N, typename SUBNET> using ares_down = dlib::relu<residual_down<block,N,dlib::affine,SUBNET>>;

template <typename SUBNET> using alevel0 = ares_down<256,SUBNET>;
template <typename SUBNET> using alevel1 = ares<256,ares<256,ares_down<256,SUBNET>>>;
template <typename SUBNET> using alevel2 = ares<128,ares<128,ares_down<128,SUBNET>>>;
template <typename SUBNET> using alevel3 = ares<64,ares<64,ares<64,ares_down<64,SUBNET>>>>;
template <typename SUBNET> using alevel4 = ares<32,ares<32,ares<32,SUBNET>>>;

using face_recognition_dnn_model = dlib::loss_metric<dlib::fc_no_bias<128,dlib::avg_pool_everything<
                                             alevel0<
                                                     alevel1<
                                                             alevel2<
                                                                     alevel3<
                                                                             alevel4<
                                                                                     dlib::max_pool<3,3,2,2,dlib::relu<dlib::affine<dlib::con<32,7,7,2,2,
                                                                                     dlib::input_rgb_image_sized<150>
                                                                     >>>>>>>>>>>>;


#endif //FACE_DETECTION_DNN_FACE_RECOGNITION_MODEL_H

main.cpp

#include <iostream>

// Load Image
#include <dlib/image_io.h>

// Shape predictor
// dlib::shape_predictor
// landmarks: http://dlib.net/files/shape_predictor_68_face_landmarks.dat.bz2
#include <dlib/image_processing/shape_predictor.h>
// Face detector
// dlib::frontal_face_detector
#include <dlib/image_processing/frontal_face_detector.h>
// Render face landmarks (for win overlays)
// dlib::render_face_detections
#include <dlib/image_processing/render_face_detections.h>

// face_recognition_dnn_model
#include "dnn_face_recognition_model.h"

// Gui
#include <dlib/gui_widgets.h>

void ShowImage(const dlib::array2d<dlib::rgb_pixel>& image) {
    dlib::image_window win;
    win.set_image(image);

    // using of title creates
    // memory leak at least on MacOS
    // win.set_title(title)

    win.wait_until_closed();
}

int main(int argc, char** argv) {
    if (argc <= 3) {
        std::cout
            << "Call app with the image param" << std::endl
            << "./face_detection image_name" << std::endl;
        return 1;
    }

    dlib::frontal_face_detector detector = dlib::get_frontal_face_detector();

    dlib::shape_predictor shape_predictor;
    // shape_predictor_68_face_landmarks.dat
    dlib::deserialize(argv[1]) >> shape_predictor;

    face_recognition_dnn_model face_recognition_dnn_model;
    // dlib_face_recognition_resnet_model_v1.dat
    dlib::deserialize(argv[2]) >> face_recognition_dnn_model;

    dlib::image_window win;

    for (int i = 3; i < argc; i++) {
        dlib::array2d<dlib::rgb_pixel> image;
        dlib::load_image(image, argv[i]);
        dlib::pyramid_up(image);

        std::vector<dlib::matrix<dlib::rgb_pixel>> face_images;
        std::vector<dlib::rectangle> face_rectangles = detector(image);

        std::vector<dlib::full_object_detection> faces_landmarks;
        for (const auto& face_rectangle: face_rectangles) {
            dlib::full_object_detection landmarks = shape_predictor(image, face_rectangle);
            faces_landmarks.push_back(landmarks);

            dlib::matrix<dlib::rgb_pixel> face_image;
            dlib::extract_image_chip(image, dlib::get_face_chip_details(landmarks, 150, 0.25), face_image);

            face_images.push_back(std::move(face_image));
        }

        win.clear_overlay();
        win.set_image(image);
        // add red faces rectangle
        win.add_overlay(face_rectangles);
        win.add_overlay(dlib::render_face_detections(faces_landmarks));

        std::vector<dlib::matrix<float, 0, 1>> face_descriptors = face_recognition_dnn_model(face_images);

        std::cout << argv[i] << std::endl;
        for (size_t di = 0; di < face_descriptors.size(); di++) {
            auto& face_descriptor = face_descriptors[di];

            std::cout << "face " << di << ": [";
            for (auto iterator = face_descriptor.begin(); iterator < face_descriptor.end(); iterator++) {
                std::cout << *iterator << ", ";
            }
            std::cout << "]" << std::endl;
        }

        if (i < argc - 1) {
            std::cout << "Press any button to continue..." << std::endl;
            std::cin.get();
        }
    }

    win.wait_until_closed();

    return 0;
}