Gtkmm Show Image MainWindow

#include <gtkmm.h>

#include <iostream>
#include <cstring>
#include <vector>

class MainWindow
:
    public Gtk::Window
{
public:

    MainWindow();
    virtual ~MainWindow() {}

private:

    Gtk::Image image;
    Glib::RefPtr<Gdk::Pixbuf> ref_orig, ref_dest;

};

MainWindow::MainWindow()
:
    ref_orig (Gdk::Pixbuf::create_from_file ("./image.png"))
{
    set_title ("Show Image");
    set_position (Gtk::WIN_POS_CENTER);

    const guint8* raw = ref_orig->get_pixels();
    const std::vector<guint8> image_pixels (raw, raw + ref_orig->get_byte_length());

    ref_dest =
        Gdk::Pixbuf::create_from_data (
            image_pixels.data(), Gdk::COLORSPACE_RGB,
            ref_orig->get_has_alpha(), ref_orig->get_bits_per_sample(),
            ref_orig->get_width(), ref_orig->get_height(), ref_orig->get_rowstride());

    image.set (ref_dest);

    add (image);

    show_all_children();
}

int main (int argc, char *argv[])
{
    Glib::RefPtr<Gtk::Application> app = Gtk::Application::create();

    MainWindow main_window;

    return app->run (main_window);
}