如何在Unity3d实现多路RTSP或RTMP流播放_技术教程

在开发ar、vr或教育类产品时，许多开发者在windows平台上构建稳定且低延迟的rtsp或rtmp播放器时遇到了挑战。如果从头开始在unity3d中开发一个播放器，成本高且周期长，不适合快速推出产品。我们建议的最佳方法是集成现有的native平台上成熟且稳定的播放器，并将rgb/yuv数据回调到上层，然后在上层进行绘制。

不浪费时间了，以Windows平台上的多路播放为例：

Native播放器返回未压缩的图像格式，如RGB/YUV420/NV12等。我们将从Windows平台回调YUV数据（NT_SP_E_VIDEO_FRAME_FROMAT_I420）。本文以调用大牛|直播|SDK（Github）提供的Windows平台RTSP和RTMP播放器SDK为例，具体代码如下：

    public void Play(int sel)    {        if (videoctrl[sel].is_running)        {            Debug.Log("已经在播放..");            return;        }        lock (videoctrl[sel].frame_lock_)        {            videoctrl[sel].cur_video_frame_ = null;        }        OpenPlayer(sel);        if (videoctrl[sel].player_handle_ == IntPtr.Zero)            return;        //设置播放URL        NTSmartPlayerSDK.NT_SP_SetURL(videoctrl[sel].player_handle_, videoctrl[sel].videoUrl);        /* ++ 播放前参数配置可加在此处 ++ */        int play_buffer_time_ = 100;        NTSmartPlayerSDK.NT_SP_SetBuffer(videoctrl[sel].player_handle_, play_buffer_time_);                 //设置buffer time        int is_using_tcp = 0;        //TCP模式        NTSmartPlayerSDK.NT_SP_SetRTSPTcpMode(videoctrl[sel].player_handle_, is_using_tcp);        int timeout = 10;        NTSmartPlayerSDK.NT_SP_SetRtspTimeout(videoctrl[sel].player_handle_, timeout);        int is_auto_switch_tcp_udp = 1;        NTSmartPlayerSDK.NT_SP_SetRtspAutoSwitchTcpUdp(videoctrl[sel].player_handle_, is_auto_switch_tcp_udp);        Boolean is_mute_ = false;        NTSmartPlayerSDK.NT_SP_SetMute(videoctrl[sel].player_handle_, is_mute_ ? 1 : 0);                    //是否启动播放的时候静音        int is_fast_startup = 1;        NTSmartPlayerSDK.NT_SP_SetFastStartup(videoctrl[sel].player_handle_, is_fast_startup);              //设置快速启动模式        Boolean is_low_latency_ = false;        NTSmartPlayerSDK.NT_SP_SetLowLatencyMode(videoctrl[sel].player_handle_, is_low_latency_ ? 1 : 0);    //设置是否启用低延迟模式        //设置旋转角度(设置0， 90， 180， 270度有效，其他值无效)        int rotate_degrees = 0;        NTSmartPlayerSDK.NT_SP_SetRotation(videoctrl[sel].player_handle_, rotate_degrees);int volume = 100;NTSmartPlayerSDK.NT_SP_SetAudioVolume(videoctrl[sel].player_handle_, volume);//设置播放音量, 范围是[0, 100], 0是静音，100是最大音量, 默认是100        // 设置上传下载报速度        int is_report = 0;        int report_interval = 1;        NTSmartPlayerSDK.NT_SP_SetReportDownloadSpeed(videoctrl[sel].player_handle_, is_report, report_interval);        /* -- 播放前参数配置可加在此处 -- */        //video frame callback (YUV/RGB)        videoctrl[sel].video_frame_call_back_ = new SP_SDKVideoFrameCallBack(NT_SP_SetVideoFrameCallBack);        NTSmartPlayerSDK.NT_SP_SetVideoFrameCallBack(videoctrl[sel].player_handle_, (Int32)NT.NTSmartPlayerDefine.NT_SP_E_VIDEO_FRAME_FORMAT.NT_SP_E_VIDEO_FRAME_FROMAT_I420, window_handle_, videoctrl[sel].video_frame_call_back_);        UInt32 flag = NTSmartPlayerSDK.NT_SP_StartPlay(videoctrl[sel].player_handle_);        if (flag == DANIULIVE_RETURN_OK)        {            videoctrl[sel].is_need_get_frame_ = true;            Debug.Log("播放成功");        }        else        {            videoctrl[sel].is_need_get_frame_ = false;            Debug.LogError("播放失败");        }        videoctrl[sel].is_running = true;    }

处理回调的数据：

    private void SDKVideoFrameCallBack(UInt32 status, IntPtr frame, int sel)    {        //这里拿到回调frame，进行相关操作        NT_SP_VideoFrame video_frame = (NT_SP_VideoFrame)Marshal.PtrToStructure(frame, typeof(NT_SP_VideoFrame));        VideoFrame  u3d_frame = new VideoFrame();        u3d_frame.width_  = video_frame.width_;        u3d_frame.height_ = video_frame.height_;        u3d_frame.timestamp_ = (UInt64)video_frame.timestamp_;        int d_y_stride = video_frame.width_;        int d_u_stride = (video_frame.width_ + 1) / 2;        int d_v_stride = d_u_stride;        int d_y_size = d_y_stride * video_frame.height_;        int d_u_size = d_u_stride * ((video_frame.height_ + 1) / 2);        int d_v_size = d_u_size;        int u_v_height = ((u3d_frame.height_ + 1) / 2);        u3d_frame.y_stride_ = d_y_stride;        u3d_frame.u_stride_ = d_u_stride;        u3d_frame.v_stride_ = d_v_stride;        u3d_frame.y_data_ = new byte[d_y_size];        u3d_frame.u_data_ = new byte[d_u_size];        u3d_frame.v_data_ = new byte[d_v_size];        CopyFramePlane(u3d_frame.y_data_, d_y_stride,            video_frame.plane0_, video_frame.stride0_, u3d_frame.height_);        CopyFramePlane(u3d_frame.u_data_, d_u_stride,           video_frame.plane1_, video_frame.stride1_, u_v_height);        CopyFramePlane(u3d_frame.v_data_, d_v_stride,           video_frame.plane2_, video_frame.stride2_, u_v_height);        lock (videoctrl[sel].frame_lock_ )        {            videoctrl[sel].cur_video_frame_ = u3d_frame;            //Debug.LogError("sel: " + sel + " w:" + u3d_frame.width_ + "h:" + u3d_frame.height_);        }    }

在Unity3D中创建相应的RGB/YUV420等Shader，并获取图像数据来填充纹理：

    private void UpdateYUVTexture(VideoFrame video_frame, int sel)    {        if (video_frame.y_data_ == null || video_frame.u_data_ == null || video_frame.v_data_ == null)        {            Debug.Log("video frame with null..");            return;        }        if (videoctrl[sel].yTexture_ != null)        {            videoctrl[sel].yTexture_.LoadRawTextureData(video_frame.y_data_);            videoctrl[sel].yTexture_.Apply();        }        if (videoctrl[sel].uTexture_ != null)        {            videoctrl[sel].uTexture_.LoadRawTextureData(video_frame.u_data_);            videoctrl[sel].uTexture_.Apply();        }        if (videoctrl[sel].vTexture_ != null)        {            videoctrl[sel].vTexture_.LoadRawTextureData(video_frame.v_data_);            videoctrl[sel].vTexture_.Apply();        }    }