cv_networking_pipeline_linux/my_ndi.cpp

#include <cstdio>
#include <chrono>
#include <string>
#include <iostream>
#include <csignal>
#include <Processing.NDI.Lib.h>
#include "opencv2/opencv.hpp"
#ifdef _WIN32
#ifdef _WIN64
#pragma comment(lib, "Processing.NDI.Lib.x64.lib")
#else // _WIN64
#pragma comment(lib, "Processing.NDI.Lib.x86.lib")
#endif // _WIN64
#endif // _WIN32

using namespace std::chrono;

static bool is_terminated = false;

void signalHandler(int signum) {
    // Ctrl+C  -> SIGINT
    // SystemD -> SIGTERM
    std::cout << "Interrupt signal (" << signum << ") received.";
    is_terminated = true;
};

int main(int argc, char* argv[]) {
    if (argc < 2) {
        std::cout << "too few arguments" << std::endl;
        return -1;
    }
    signal(SIGINT, signalHandler);
    signal(SIGTERM, signalHandler);
    std::string magic_string = argv[1];
    std::cout << "we got the ndi-stream-name = " << magic_string << std::endl;

    // Not required, but "correct" (see the SDK documentation.
    if (!NDIlib_initialize()) {
        return 0;
    }
    // We are going to create an NDI finder that locates sources on the network.
    NDIlib_find_instance_t pNDI_find = NDIlib_find_create_v2();
    if (!pNDI_find) {
        return 0;
    }
    // Run for one minute
    uint32_t no_sources = 0;
    const NDIlib_source_t* p_sources = nullptr;
    int stream_offset = -1;
    while (stream_offset < 0 && !is_terminated) {
        printf("Looking for sources ...\n");
        NDIlib_find_wait_for_sources(pNDI_find, 5000/* One second */);
//        // Wait up till 5 seconds to check for new sources to be added or removed
//        if (!NDIlib_find_wait_for_sources(pNDI_find, 5000/* 5 seconds */)) {
//            printf("No change to the sources found.\n");
//            continue;
//        }
        p_sources = NDIlib_find_get_current_sources(pNDI_find, &no_sources);
        // Display all the sources.
        printf("Network sources (%u found).\n", no_sources);
        for (uint32_t i = 0; i < no_sources; i++) {
            printf("%u. %s\n", i + 1, p_sources[i].p_ndi_name);
        }
        for (uint32_t i = 0; i < no_sources; i++) {
            const auto& the_name = std::string(p_sources[i].p_ndi_name);
            if (the_name == magic_string) {
                stream_offset = static_cast<int>(i);
                std::cout << "selecting the stream [" << the_name << "] with the index = " << i << std::endl;
                break;
            } else {
                std::cout << "the stream [" << the_name << "] noes not match.  index = " << i << std::endl;
            }
        }
        if (stream_offset >= 0) {
            std::cout << "found the stream" << std::endl;
            break;
        }
        std::cout << "no such stream" << std::endl;
    }

    // We now have at least one source, so we create a receiver to look at it.
    NDIlib_recv_instance_t pNDI_recv = NDIlib_recv_create_v3();
    if (!pNDI_recv) {
        return 0;
    }

    // Connect to our sources
    NDIlib_recv_connect(pNDI_recv, p_sources + stream_offset);

    // Destroy the NDI finder. We needed to have access to the pointers to p_sources[0]
    NDIlib_find_destroy(pNDI_find);

    // Run for one minute
    using namespace std::chrono;
    int counter = 0;
    cv::namedWindow("test2");
    while (!is_terminated) {
        counter += 1;
        // The descriptors
        NDIlib_video_frame_v2_t video_frame;
//        NDIlib_audio_frame_v3_t audio_frame;
        NDIlib_metadata_frame_t metadata_frame;
        const auto& timeout = 5000;

        const auto& ret = NDIlib_recv_capture_v3(pNDI_recv, &video_frame, nullptr, &metadata_frame, timeout);
        switch (ret) {
            case NDIlib_frame_type_none: { // No data
                printf("No data received.\n");
                break;
            }
            case NDIlib_frame_type_video: { // Video data
                printf("%d -- Video data received (%dx%d).\n", counter, video_frame.xres, video_frame.yres);
                std::cout << "timestand & timecode: " << video_frame.timestamp << " " << video_frame.timecode << std::endl;
                std::cout << "The frame format type is: " << video_frame.frame_format_type << std::endl;
                std::cout << "The type of data in the frame is: " << video_frame.FourCC << std::endl;
                int len = 0;
                if (video_frame.p_metadata) {
                    for (int i = 0; ; ++i) {
                        // std::cout << i << std::endl;
                        if (video_frame.p_metadata[i] == 0) {
                            len = i;
                            break;
                        }
                    }
                    std::cout << "metadata len = " << len << " "
                              << std::string(video_frame.p_metadata)
                              << std::endl;
                } else {
                    std::cout << "video_frame.p_metadata is nullptr" << std::endl;
                    std::cout << "metadata len = " << len << std::endl;
                }
                auto p_data = video_frame.p_data;
                std::cout << "The frame format type is: " << video_frame.frame_format_type << std::endl;
                cv::Mat frame(video_frame.yres, video_frame.xres, CV_8UC4, p_data);
                std::cout << "The frame dimensions: " << frame.cols << " " << frame.rows << std::endl;
                cv::imshow("test2", frame);
                cv::waitKey(0);

                std::cout << "space (video frame)" << std::endl;
                NDIlib_recv_free_video_v2(pNDI_recv, &video_frame);
                break;
            }
//            case NDIlib_frame_type_audio: { // Audio data
//                printf("Audio data received (%d samples).\n", audio_frame.no_samples);
//                NDIlib_recv_free_audio_v3(pNDI_recv, &audio_frame);
//                break;
//            }
            case NDIlib_frame_type_metadata: {
                printf("Metadata received (%d length).\n", metadata_frame.length);
                std::cout << std::string(metadata_frame.p_data) << std::endl;
                std::cout << "space (metadata)" << std::endl;
                NDIlib_recv_free_metadata(pNDI_recv, &metadata_frame);
                break;
            }
            default:
                printf("other case");
                std::cout << ret << std::endl;
        }
    }

    // Destroy the receiver
    NDIlib_recv_destroy(pNDI_recv);

    // Not required, but nice
    NDIlib_destroy();

    // Finished
    return 0;
}