Windows平台Unity3d下如何同时播放多路RTSP或RTMP流

好多开发者在做AR、VR或者教育类产品时，苦于如何在windows平台构建一个稳定且低延迟的RTSP或者RTMP播放器，如果基于Unity3d完全重新开发一个播放器，代价大、而且周期长，不适合快速出产品，我们认为当前最好的方式就是集成现有Native平台上成熟稳定播放器，回调rgb/yuv数据到上层，上层做绘制即可。

废话不多说，以Windows平台多路播放为例：

1.Native播放器SDK支持吐RGB/YUV420/NV12等其中的一种未压缩的图像格式

比如Windows平台，我们回调YUV上来（NT_SP_E_VIDEO_FRAME_FROMAT_I420），本文以调用大牛直播SDK(Github)的Windows平台RTSP、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URLNTSmartPlayerSDK.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 timeint 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;}

2. 处理回调上来的数据

    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_);}}

3.Unity3D创建相应的RGB/YUV420等Shader，获取图像数据来填充纹理即可

    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();}}