Windows下如何实现Unity3D下的RTMP推送

好多开发者苦于很难在unity3d下实现RTMP直播推送，本次以大牛直播SDK（Github）的Windows平台RTMP推送模块（以推摄像头为例，如需推屏幕数据，设置相关参数即可）为例，介绍下unity3d的RTMP推送集成。

简单来说，Unity3D环境下，可以直接调用C#的接口封装，针对此，我们先做了一层封装 （nt_publisher_wrapper.cs），核心代码如下：

初始化和基础参数设置：

       private bool InitSDK()
        {
            if (!is_pusher_sdk_init_)
            {
                // 设置日志路径(请确保目录存在)
                String log_path = "D:\pulisherlog";
                NTSmartLog.NT_SL_SetPath(log_path);

                UInt32 isInited = NTSmartPublisherSDK.NT_PB_Init(0, IntPtr.Zero);

                if (isInited != 0)
                {
                    Debug.Log("调用NT_PB_Init失败..");
                    return false;
                }

                is_pusher_sdk_init_ = true;
            }

            return true;
        }

        public bool OpenPublisherHandle(uint video_option, uint audio_option)
        {
            if (publisher_handle_ != IntPtr.Zero)
            {
                return true;
            }

            publisher_handle_count_ = 0;

            if (NTBaseCodeDefine.NT_ERC_OK != NTSmartPublisherSDK.NT_PB_Open(out publisher_handle_,
                video_option, audio_option, 0, IntPtr.Zero))
            {
                return false;
            }

            if (publisher_handle_ != IntPtr.Zero)
            {
                pb_event_call_back_ = new NT_PB_SDKEventCallBack(PbEventCallBack);

                NTSmartPublisherSDK.NT_PB_SetEventCallBack(publisher_handle_, IntPtr.Zero, pb_event_call_back_);

                return true;
            }
            else
            {
                return false;
            }
        }

        private void SetCommonOptionToPublisherSDK()
        {
            if (!IsPublisherHandleAvailable())
            {
                Debug.Log("SetCommonOptionToPublisherSDK, publisher handle with null..");
                return;
            }

            CameraInfo camera = cameras_[cur_sel_camera_index_];
            NT_PB_VideoCaptureCapability cap = camera.capabilities_[cur_sel_camera_resolutions_index_];

            SetVideoCaptureDeviceBaseParameter(camera.id_.ToString(), (UInt32)cap.width_, (UInt32)cap.height_);

            SetFrameRate((UInt32)CalBitRate(edit_key_frame_, cap.width_, cap.height_));

            SetVideoEncoderType(is_h264_encoder ? 1 : 2);

            SetVideoQualityV2(CalVideoQuality(cap.width_, cap.height_, is_h264_encoder));

            SetVideoMaxBitRate((CalMaxKBitRate(edit_key_frame_, cap.width_, cap.height_, false)));

            SetVideoKeyFrameInterval((edit_key_frame_));

            if (is_h264_encoder)
            {
                SetVideoEncoderProfile(1);

            }

            SetVideoEncoderSpeed(CalVideoEncoderSpeed(cap.width_, cap.height_, is_h264_encoder));

            // 音频相关设置

            SetAuidoInputDeviceId(0);

            SetPublisherAudioCodecType(1);

            SetPublisherMute(is_mute);

            SetInputAudioVolume(Convert.ToSingle(edit_audio_input_volume_));
        }

预览、停止预览：

       public bool StartPreview()
        {
            if(CheckPublisherHandleAvailable() == false)
                return false;

            video_preview_image_callback_ = new NT_PB_SDKVideoPreviewImageCallBack(SDKVideoPreviewImageCallBack);

            NTSmartPublisherSDK.NT_PB_SetVideoPreviewImageCallBack(publisher_handle_, (int)NTSmartPublisherDefine.NT_PB_E_IMAGE_FORMAT.NT_PB_E_IMAGE_FORMAT_RGB32, IntPtr.Zero, video_preview_image_callback_);

            if (NTBaseCodeDefine.NT_ERC_OK != NTSmartPublisherSDK.NT_PB_StartPreview(publisher_handle_, 0, IntPtr.Zero))
            {
                if (0 == publisher_handle_count_)
                {
                    NTSmartPublisherSDK.NT_PB_Close(publisher_handle_);
                    publisher_handle_ = IntPtr.Zero;
                }

                return false;
            }

            publisher_handle_count_++;

            is_previewing_ = true;

            return true;
        }

        public void StopPreview()
        {
            if (is_previewing_ == false) return;

            is_previewing_ = false;

            publisher_handle_count_--;
            NTSmartPublisherSDK.NT_PB_StopPreview(publisher_handle_);

            if (0 == publisher_handle_count_)
            {
                NTSmartPublisherSDK.NT_PB_Close(publisher_handle_);
                publisher_handle_ = IntPtr.Zero;
            }
        }

开始推送、停止推送：

        public bool StartPublisher(String url)
        {
            if (CheckPublisherHandleAvailable() == false) return false;

            if (publisher_handle_ == IntPtr.Zero)
            {
                return false;
            }
            if (!String.IsNullOrEmpty(url))
            {
                NTSmartPublisherSDK.NT_PB_SetURL(publisher_handle_, url, IntPtr.Zero);
            }

            if (NTBaseCodeDefine.NT_ERC_OK != NTSmartPublisherSDK.NT_PB_StartPublisher(publisher_handle_, IntPtr.Zero))
            {
                if (0 == publisher_handle_count_)
                {
                    NTSmartPublisherSDK.NT_PB_Close(publisher_handle_);
                    publisher_handle_ = IntPtr.Zero;
                }

                is_publishing_ = false;

                return false;
            }

            publisher_handle_count_++;

            is_publishing_ = true;

            return true;
        }

        public void StopPublisher()
        {
            if (is_publishing_ == false) return;

            publisher_handle_count_--;
            NTSmartPublisherSDK.NT_PB_StopPublisher(publisher_handle_);

            if (0 == publisher_handle_count_)
            {
                NTSmartPublisherSDK.NT_PB_Close(publisher_handle_);
                publisher_handle_ = IntPtr.Zero;
            }

            is_publishing_ = false;
        }

相关event事件回调：

        private void PbEventCallBack(IntPtr handle, IntPtr user_data, 
            UInt32 event_id,
            Int64 param1,
            Int64 param2,
            UInt64 param3,
            UInt64 param4,
            [MarshalAs(UnmanagedType.LPStr)] String param5,
            [MarshalAs(UnmanagedType.LPStr)] String param6,
            IntPtr param7)
        {
            String event_log = "";

            switch (event_id)
            {
                case (uint)NTSmartPublisherDefine.NT_PB_E_EVENT_ID.NT_PB_E_EVENT_ID_CONNECTING:
                    event_log = "连接中";
                    if (!String.IsNullOrEmpty(param5))
                    {
                        event_log = event_log + " url:" + param5;
                    }
                    break;

                case (uint)NTSmartPublisherDefine.NT_PB_E_EVENT_ID.NT_PB_E_EVENT_ID_CONNECTION_FAILED:
                    event_log = "连接失败";
                    if (!String.IsNullOrEmpty(param5))
                    {
                        event_log = event_log + " url:" + param5;
                    }
                    break;

                case (uint)NTSmartPublisherDefine.NT_PB_E_EVENT_ID.NT_PB_E_EVENT_ID_CONNECTED:
                    event_log = "已连接";
                    if (!String.IsNullOrEmpty(param5))
                    {
                        event_log = event_log + " url:" + param5;
                    }
                    break;

                case (uint)NTSmartPublisherDefine.NT_PB_E_EVENT_ID.NT_PB_E_EVENT_ID_DISCONNECTED:
                    event_log = "断开连接";
                    if (!String.IsNullOrEmpty(param5))
                    {
                        event_log = event_log + " url:" + param5;
                    }
                    break;

                default:
                    break;
            }

            if(OnLogEventMsg != null) OnLogEventMsg.Invoke(event_id, event_log);
        }

SmartPublishWinMono.cs 调用上述封装的代码即可，本地预览的话，拿到回调的RGB数据，在unity3d上层刷下即可，如下图：

​

经测试，unity3d下，RTMP推送，配合RTMP播放端，依然可以实现毫秒级延迟的推拉流体验。