OpenTera WebRTC C++ Library API Documentation

Table of Contents

• Examples
  • Data Channel Client Example
  • Video Stream Client Example

Examples

Data Channel Client Example

#include <OpenteraWebrtcNativeClient/DataChannelClient.h>
 
#include <iostream>
 
using namespace opentera;
using namespace std;
 
int main(int argc, char* argv[])
{
    vector<IceServer> iceServers;
    if (!IceServer::fetchFromServer("http://localhost:8080/iceservers", "abc", iceServers))
    {
        cout << "IceServer::fetchFromServer failed" << endl;
        iceServers.clear();
    }
 
    auto signalingServerConfiguration =
        SignalingServerConfiguration::create("ws://localhost:8080/signaling", "C++", "chat", "abc");
    auto webrtcConfiguration = WebrtcConfiguration::create(iceServers);
    auto dataChannelConfiguration = DataChannelConfiguration::create();
    DataChannelClient client(signalingServerConfiguration, webrtcConfiguration, dataChannelConfiguration);
 
    client.setOnSignalingConnectionOpened(
        []()
        {
            // This callback is called from the internal client thread.
            cout << "OnSignalingConnectionOpened" << endl;
        });
    client.setOnSignalingConnectionClosed(
        []()
        {
            // This callback is called from the internal client thread.
            cout << "OnSignalingConnectionClosed" << endl;
        });
    client.setOnSignalingConnectionError(
        [](const string& error)
        {
            // This callback is called from the internal client thread.
            cout << "OnSignalingConnectionError:" << endl << "\t" << error;
        });
 
    client.setOnRoomClientsChanged(
        [](const vector<RoomClient>& roomClients)
        {
            // This callback is called from the internal client thread.
            cout << "OnRoomClientsChanged:" << endl;
            for (const auto& c : roomClients)
            {
                cout << "\tid=" << c.id() << ", name=" << c.name() << ", isConnected=" << c.isConnected() << endl;
            }
        });
 
    client.setOnClientConnected(
        [](const Client& client)
        {
            // This callback is called from the internal client thread.
            cout << "OnClientConnected:" << endl;
            cout << "\tid=" << client.id() << ", name=" << client.name() << endl;
        });
    client.setOnClientDisconnected(
        [](const Client& client)
        {
            // This callback is called from the internal client thread.
            cout << "OnClientDisconnected:" << endl;
            cout << "\tid=" << client.id() << ", name=" << client.name() << endl;
        });
    client.setOnClientConnectionFailed(
        [](const Client& client)
        {
            // This callback is called from the internal client thread.
            cout << "OnClientConnectionFailed:" << endl;
            cout << "\tid=" << client.id() << ", name=" << client.name() << endl;
        });
 
    client.setOnError(
        [](const string& error)
        {
            // This callback is called from the internal client thread.
            cout << "error:" << endl;
            cout << "\t" << error << endl;
        });
 
    client.setLogger(
        [](const string& message)
        {
            // This callback is called from the internal client thread.
            cout << "log:" << endl;
            cout << "\t" << message << endl;
        });
 
    client.setOnDataChannelOpened(
        [](const Client& client)
        {
            // This callback is called from the internal client thread.
            cout << "OnDataChannelOpened:" << endl;
            cout << "\tid=" << client.id() << ", name=" << client.name() << endl;
        });
    client.setOnDataChannelClosed(
        [](const Client& client)
        {
            // This callback is called from the internal client thread.
            cout << "OnDataChannelClosed:" << endl;
            cout << "\tid=" << client.id() << ", name=" << client.name() << endl;
        });
    client.setOnDataChannelError(
        [](const Client& client, const string& error)
        {
            // This callback is called from the internal client thread.
            cout << "OnDataChannelError:" << endl;
            cout << "\tid=" << client.id() << ", name=" << client.name() << endl;
            cout << "\t" << error << endl;
        });
    client.setOnDataChannelMessageString(
        [](const Client& client, const string& message)
        {
            // This callback is called from the internal client thread.
            cout << "setOnDataChannelMessageString:" << endl;
            cout << "\tid=" << client.id() << ", name=" << client.name() << endl;
            cout << "\t" << message << endl;
        });
 
    client.connect();
 
    cin.get();
 
    return 0;
}

Video Stream Client Example

#include <OpenteraWebrtcNativeClient/StreamClient.h>
 
#include <opencv2/core.hpp>
#include <opencv2/videoio.hpp>
#include <opencv2/highgui.hpp>
 
#include <cmath>
#include <iostream>
#include <thread>
#include <vector>
#include <cstdlib>
 
using namespace opentera;
using namespace std;
 
class CvVideoCaptureVideoSource : public VideoSource
{
    atomic_bool m_stopped;
    thread m_thread;
    string m_path;
 
public:
    CvVideoCaptureVideoSource(string path)
        : VideoSource(VideoSourceConfiguration::create(false, true)),
          m_stopped(false),
          m_thread(&CvVideoCaptureVideoSource::run, this),
          m_path(move(path))
    {
    }
 
    ~CvVideoCaptureVideoSource() override
    {
        m_stopped.store(true);
        m_thread.join();
    }
 
private:
    void run()
    {
        cv::VideoCapture cap;
        cv::Mat bgrImg;
 
        while (!m_stopped.load())
        {
            cap.open(m_path);
            if (!cap.isOpened())
            {
                cerr << "Invalid video file" << endl;
                exit(EXIT_FAILURE);
            }
 
            auto frameDuration = chrono::microseconds(static_cast<int>(1e6 / cap.get(cv::CAP_PROP_FPS)));
            auto frameTime = chrono::steady_clock::now();
            while (!m_stopped.load())
            {
                cap.read(bgrImg);
                if (bgrImg.empty())
                {
                    break;
                }
 
                int64_t timestampUs =
                    chrono::duration_cast<chrono::microseconds>(chrono::steady_clock::now().time_since_epoch()).count();
                sendFrame(bgrImg, timestampUs);
 
                frameTime += frameDuration;
                this_thread::sleep_until(frameTime);
            }
        }
    }
};
 
constexpr uint32_t SoundCardTotalDelayMs = 0;
constexpr int BitsPerSample = 16;
constexpr int SampleRate = 48000;
constexpr size_t NumberOfChannels = 1;
constexpr chrono::milliseconds SinAudioSourceFrameDuration = 10ms;
constexpr chrono::milliseconds SinAudioSourceSleepBuffer = 2ms;
constexpr int16_t SinAudioSourceAmplitude = 15000;
 
class SinAudioSource : public AudioSource
{
    atomic_bool m_stopped;
    thread m_thread;
 
public:
    SinAudioSource()
        : AudioSource(
              AudioSourceConfiguration::create(SoundCardTotalDelayMs),
              BitsPerSample,
              SampleRate,
              NumberOfChannels),
          m_stopped(false),
          m_thread(&SinAudioSource::run, this)
    {
    }
 
    ~SinAudioSource() override
    {
        m_stopped.store(true);
        m_thread.join();
    }
 
private:
    void run()
    {
        vector<int16_t> data(SinAudioSourceFrameDuration.count() * SampleRate / 1000, 0);
        double t = 0;
        for (size_t i = 0; i < data.size(); i++)
        {
            data[i] = static_cast<int16_t>(SinAudioSourceAmplitude * sin(t));
            t += 2 * M_PI / static_cast<double>(data.size());
        }
 
        while (!m_stopped.load())
        {
            sendFrame(data.data(), data.size() * sizeof(int16_t) / bytesPerFrame());
 
            auto start = chrono::steady_clock::now();
            this_thread::sleep_for(SinAudioSourceFrameDuration - SinAudioSourceSleepBuffer);
            while ((chrono::steady_clock::now() - start) < SinAudioSourceFrameDuration);
        }
    }
};
 
int main(int argc, char* argv[])
{
    if (argc != 2)
    {
        cout << "Usage: CppStreamClient video_path" << endl;
        return EXIT_FAILURE;
    }
 
    vector<IceServer> iceServers;
    if (!IceServer::fetchFromServer("http://localhost:8080/iceservers", "abc", iceServers))
    {
        cout << "IceServer::fetchFromServer failed" << endl;
        iceServers.clear();
    }
 
    auto signalingServerConfiguration =
        SignalingServerConfiguration::create("ws://localhost:8080/signaling", "C++", "chat", "abc");
    auto webrtcConfiguration = WebrtcConfiguration::create(iceServers);
    auto videoStreamConfiguration = VideoStreamConfiguration::create();
    auto videoSource = make_shared<CvVideoCaptureVideoSource>(argv[1]);
    auto audioSource = make_shared<SinAudioSource>();
    StreamClient
        client(signalingServerConfiguration, webrtcConfiguration, videoStreamConfiguration, videoSource, audioSource);
 
    client.setOnSignalingConnectionOpened(
        []()
        {
            // This callback is called from the internal client thread.
            cout << "OnSignalingConnectionOpened" << endl;
        });
    client.setOnSignalingConnectionClosed(
        []()
        {
            // This callback is called from the internal client thread.
            cout << "OnSignalingConnectionClosed" << endl;
        });
    client.setOnSignalingConnectionError(
        [](const string& error)
        {
            // This callback is called from the internal client thread.
            cout << "OnSignalingConnectionError:" << endl << "\t" << error;
        });
 
    client.setOnRoomClientsChanged(
        [](const vector<RoomClient>& roomClients)
        {
            // This callback is called from the internal client thread.
            cout << "OnRoomClientsChanged:" << endl;
            for (const auto& c : roomClients)
            {
                cout << "\tid=" << c.id() << ", name=" << c.name() << ", isConnected=" << c.isConnected() << endl;
            }
        });
 
    client.setOnClientConnected(
        [](const Client& client)
        {
            // This callback is called from the internal client thread.
            cout << "OnClientConnected:" << endl;
            cout << "\tid=" << client.id() << ", name=" << client.name() << endl;
            cv::namedWindow(client.id(), cv::WINDOW_AUTOSIZE);
        });
    client.setOnClientDisconnected(
        [](const Client& client)
        {
            // This callback is called from the internal client thread.
            cout << "OnClientDisconnected:" << endl;
            cout << "\tid=" << client.id() << ", name=" << client.name() << endl;
            cv::destroyWindow(client.id());
        });
    client.setOnClientConnectionFailed(
        [](const Client& client)
        {
            // This callback is called from the internal client thread.
            cout << "OnClientConnectionFailed:" << endl;
            cout << "\tid=" << client.id() << ", name=" << client.name() << endl;
        });
 
    client.setOnError(
        [](const string& error)
        {
            // This callback is called from the internal client thread.
            cout << "error:" << endl;
            cout << "\t" << error << endl;
        });
 
    client.setLogger(
        [](const string& message)
        {
            // This callback is called from the internal client thread.
            cout << "log:" << endl;
            cout << "\t" << message << endl;
        });
 
    client.setOnAddRemoteStream(
        [](const Client& client)
        {
            // This callback is called from the internal client thread.
            cout << "OnAddRemoteStream:" << endl;
            cout << "\tid=" << client.id() << ", name=" << client.name() << endl;
        });
    client.setOnRemoveRemoteStream(
        [](const Client& client)
        {
            // This callback is called from the internal client thread.
            cout << "OnRemoveRemoteStream:" << endl;
            cout << "\tid=" << client.id() << ", name=" << client.name() << endl;
        });
    client.setOnVideoFrameReceived(
        [](const Client& client, const cv::Mat& bgrImg, uint64_t timestampUs)
        {
            // This callback is called from a WebRTC processing thread.
            cout << "OnVideoFrameReceived:" << endl;
            cv::imshow(client.id(), bgrImg);
            cv::waitKey(1);
        });
    client.setOnAudioFrameReceived(
        [](const Client& client,
           const void* audioData,
           int bitsPerSample,
           int sampleRate,
           size_t numberOfChannels,
           size_t numberOfFrames)
        {
            // This callback is called from a WebRTC processing thread.
            cout << "OnAudioFrameReceived:" << endl;
            cout << "\tid=" << client.id() << ", name=" << client.name() << endl;
            cout << "\tbitsPerSample=" << bitsPerSample << ", sampleRate = " << sampleRate;
            cout << ", numberOfChannels = " << numberOfChannels << ", numberOfFrames=" << numberOfFrames << endl;
        });
    client.setOnMixedAudioFrameReceived(
        [](const void* audioData, int bitsPerSample, int sampleRate, size_t numberOfChannels, size_t numberOfFrames)
        {
            // This callback is called from the audio device module thread.
            cout << "OnMixedAudioFrameReceived:" << endl;
            cout << "\tbitsPerSample=" << bitsPerSample << ", sampleRate=" << sampleRate;
            cout << ", numberOfChannels=" << numberOfChannels << ", numberOfFrames=" << numberOfFrames << endl;
        });
 
    client.connect();
 
    cin.get();
 
    return 0;
}