Method convert_to_numpy

dlib/python/numpy_image.h:211–241

    private:
        static py::array_t<typename pixel_traits<pixel_type>::basic_pixel_type, py::array::c_style> convert_to_numpy(matrix<pixel_type>&& img)
        {
            using basic_pixel_type = typename pixel_traits<pixel_type>::basic_pixel_type;
            const size_t dtype_size = sizeof(basic_pixel_type);
            const auto rows = static_cast<const size_t>(num_rows(img));
            const auto cols = static_cast<const size_t>(num_columns(img));
            const size_t channels = pixel_traits<pixel_type>::num;
            const size_t image_size = dtype_size * rows * cols * channels;

            std::unique_ptr<pixel_type[]> arr_ptr = img.steal_memory();
            basic_pixel_type* arr = (basic_pixel_type *) arr_ptr.release();

            if (channels == 1)
            {
                return pybind11::template array_t<basic_pixel_type, py::array::c_style>(
                    {rows, cols},                                                       // shape
                    {dtype_size*cols, dtype_size},                                      // strides
                    arr,                                                                // pointer
                    pybind11::capsule{ arr, [](void *arr_p) { delete[] reinterpret_cast<basic_pixel_type*>(arr_p); } }
                );
            }
            else
            {
                return pybind11::template array_t<basic_pixel_type, py::array::c_style>(
                    {rows, cols, channels},                                                     // shape
                    {dtype_size * cols * channels, dtype_size * channels, dtype_size},          // strides
                    arr,                                                                        // pointer
                    pybind11::capsule{ arr, [](void *arr_p) { delete[] reinterpret_cast<basic_pixel_type*>(arr_p); } }
                );
            }
        }

    };