tensor3_to_cv_mat.cpp

// Example code for how to:
// - convert an OpenCV image to an fdeep::tensor5
// - convert an fdeep::tensor5 to an OpenCV image

// compile with:
// g++ -std=c++14 -O3 tensor3_to_cv_mat.cpp -lopencv_core -lopencv_imgproc -lopencv_imgcodecs -lopencv_highgui -o tensor3_to_cv_mat

#include <fdeep/fdeep.hpp>
#include <opencv2/opencv.hpp>

int main()
{
    const cv::Mat image1 = cv::imread("image.jpg");

    // convert cv::Mat to fdeep::tensor5 (image1 to tensor)
    const fdeep::tensor5 tensor =
        fdeep::tensor5_from_bytes(image1.ptr(),
            image1.rows, image1.cols, image1.channels());

    // choose the correct pixel type for cv::Mat (gray or RGB/BGR)
    assert(tensor.shape().depth_ == 1 || tensor.shape().depth_ == 3);
    const int mat_type = tensor.shape().depth_ == 1 ? CV_8UC1 : CV_8UC3;

    // convert fdeep::tensor5 to cv::Mat (tensor to image2)
    const cv::Mat image2(
        cv::Size(tensor.shape().width_, tensor.shape().height_), mat_type);
    fdeep::tensor5_into_bytes(tensor,
        image2.data, image2.rows * image2.cols * image2.channels());

    // show both images for visual verification
    cv::imshow("image1", image1);
    cv::imshow("image2", image2);
    cv::waitKey();
}