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I'm trying to pipe a cv::mat variable from one C program to an other they are independent of each other. I already create a basic code sourced from forums and search, I have 2 programs, writer.c and reader.c. The writer.c have a cv::mat img variable in it and I need pipe it to reader.c cv::mat img to be showed up with imshow();

I'm merging code from multiple sources hoping this work, because I can find a working sample

My sources:

https://stackoverflow.com/a/2789967/11632453

https://stackoverflow.com/a/30274548/11632453

https://unix.stackexchange.com/questions/222075/pipe-named-fifo

https://stackoverflow.com/a/36080965/11632453

This is my evolution until now:

Code from file writer.c

#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <iostream>
#include "opencv2/imgproc/imgproc.hpp"


using namespace cv;
using namespace std;

int main()
{
    Mat img;
    img = imread("/home/filipe/Documentos/QT_Projects/FIFO_Writer/download.jpeg", CV_LOAD_IMAGE_COLOR);   // Read the file

    if(! img.data )                              // Check for invalid input
    {
        cout <<  "Could not open or find the image" << std::endl ;
        return -1;
    }

    namedWindow( "Display window", WINDOW_AUTOSIZE );// Create a window for display.
    imshow( "Display window", img );
    //waitKey(0); // Wait for a keystroke in the window
    //return 0;




    int fd;
    char * myfifo = "/tmp/myfifo";

    // create the FIFO (named pipe)
    mkfifo(myfifo, 0666);

    // write "Hi" to the FIFO
    fd = open(myfifo, O_WRONLY);
    //write(fd, "Hi", sizeof("Hi"));
    write(fd, img.data, sizeof(img.data));
    close(fd);

    // remove the FIFO
    unlink(myfifo);

    return 0;
}

Code from reader.c

#include <fcntl.h>
#include <stdio.h>
#include <sys/stat.h>
#include <unistd.h>
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <iostream>
#include "opencv2/imgproc/imgproc.hpp"

using namespace cv;
using namespace std;

#define MAX_BUF 1024

int main()
{
    int fd;
    char * myfifo = "/tmp/myfifo";
    char buf[MAX_BUF];

    /* open, read, and display the message from the FIFO */
    fd = open(myfifo, O_RDONLY);
    read(fd, buf, MAX_BUF);
    printf("Received: %s\n", buf);
    close(fd);

    Mat img(177, 284, CV_8UC3, Scalar(0, 0, 0));

    img.data= ((unsigned char*) (buf));
    namedWindow( "Display window", WINDOW_AUTOSIZE );// Create a window for display.
    imshow( "Display window", img );

    waitKey(0); // Wait for a keystroke in the window
    return 0;
}

I got no errors from this code, but, I got no Image ether no window apear to be created to show the image.

Any help? Anything to help me passing through? Any direction?

thanks