像Unity3D下的RTMP或RTSP播放器一样，好多开发者苦于在Unity环境下，如何高效率低延迟的把数据采集并编码实时推送到流媒体服务器，实现Unity场景下的低延迟推拉流方案。
关于屏幕采集，有两种方案：
1. 直接封装Android原生的屏幕采集工程，在unity提供接口，拿到屏幕权限后，获取屏幕数据并推送；
具体可以参考 https://blog.csdn.net/renhui1112/article/details/106750891
2. 如果只需要拿到Unity的窗体或摄像机数据推出去，可在Unity下获取到需要推送的原始数据，然后封装原生的RTMP推流接口，调用原生SDK实现数据推送，这种做法的好处是，可以自定义需要采集的数据内容，只要按照原生SDK提供的接口，完成数据对接即可，具体实现参看本文。
Android平台Unity3D的RTSP或RTMP播放器，可以参考
https://blog.csdn.net/renhui1112/article/details/104154788
本文以Android平台为例，介绍下Unity环境下的Android平台RTMP推流，数据采集在Unity完成，数据编码推送，调用大牛直播SDK（官方）Android平台RTMP直播推送SDK原生库对外二次封装的接口，高效率的实现RTMP推送。废话多说，先上图看效果。
下图系Android平台Unity环境下采集屏幕，编码推送到RTMP服务器，然后Windows平台播放器拉取RTMP流播放，为了方便看到延迟效果，特地在Android端的Unity窗口显示了当前时间，可以看到，整体延迟在毫秒级：
数据采集推送
unity数据采集相对简单，可以很轻松的拿到RGB24的数据：
texture_ = new Texture2D(video_width_, video_height_, TextureFormat.RGB24, false); texture_.ReadPixels(new Rect(0, 0, video_width_, video_height_), 0, 0, false); texture_.Apply();
然后通过调用texture_.GetRawTextureData<sbyte>(); 获取到数据即可。
拿到数据后，调用原生SDK封装的NT_PB_U3D_OnCaptureVideoRGB24PtrData()接口，完成数据投递。
简单调用流程
private void Start() { game_object_ = this.gameObject.name; AndroidJavaClass android_class = new AndroidJavaClass("com.unity3d.player.UnityPlayer"); java_obj_cur_activity_ = android_class.GetStatic<AndroidJavaObject>("currentActivity"); pusher_obj_ = new AndroidJavaObject("com.daniulive.smartpublisher.SmartPublisherUnity3d"); NT_PB_U3D_Init(); //NT_U3D_SetSDKClientKey("", "", 0); btn_encode_mode_.onClick.AddListener(OnEncodeModeBtnClicked); btn_pusher_.onClick.AddListener(OnPusherBtnClicked); btn_mute_.onClick.AddListener(OnMuteBtnClicked); }
完成接口初始化后，调用Push()接口
public void Push() { if (is_running) { Debug.Log("已推送.."); return; } if (texture_ != null) { UnityEngine.Object.Destroy(texture_); texture_ = null; } video_width_ = Screen.width; video_height_ = Screen.height; scale_width_ = (video_width_ + 1) / 2; scale_height_ = (video_height_ + 1) / 2; if (scale_width_ % 2 != 0) { scale_width_ = scale_width_ + 1; } if (scale_height_ % 2 != 0) { scale_height_ = scale_height_ + 1; } texture_ = new Texture2D(video_width_, video_height_, TextureFormat.RGB24, false); //获取输入框的url string url = input_url_.text.Trim(); if (!url.StartsWith("rtmp://")) { push_url_ = "rtmp://192.168.0.199:1935/hls/stream1"; } else { push_url_ = url; } OpenPusher(); if (pusher_handle_ == 0) return; NT_PB_U3D_Set_Game_Object(pusher_handle_, game_object_); /* ++ 推送前参数配置可加在此处 ++ */ InitAndSetConfig(); NT_PB_U3D_SetPushUrl(pusher_handle_, push_url_); /* -- 推送前参数配置可加在此处 -- */ int flag = NT_PB_U3D_StartPublisher(pusher_handle_); if (flag == DANIULIVE_RETURN_OK) { Debug.Log("推送成功.."); } else { Debug.LogError("推送失败.."); } is_running = true; }
调用OpenPusher()
private void OpenPusher() { if ( java_obj_cur_activity_ == null ) { Debug.LogError("getApplicationContext is null"); return; } int audio_opt = 1; int video_opt = 1; pusher_handle_ = NT_PB_U3D_Open(audio_opt, video_opt, video_width_, video_height_); if (pusher_handle_ != 0) Debug.Log("NT_PB_U3D_Open success"); else Debug.LogError("NT_PB_U3D_Open fail"); }
InitAndSetConfig()
private void InitAndSetConfig() { if (is_hw_encode_) { int h264HWKbps = setHardwareEncoderKbps(true, video_width_, video_height_); Debug.Log("h264HWKbps: " + h264HWKbps); int isSupportH264HWEncoder = NT_PB_U3D_SetVideoHWEncoder(pusher_handle_, h264HWKbps); if (isSupportH264HWEncoder == 0) { Debug.Log("Great, it supports h.264 hardware encoder!"); } } else { if (is_sw_vbr_mode_) //H.264 software encoder { int is_enable_vbr = 1; int video_quality = CalVideoQuality(video_width_, video_height_, true); int vbr_max_bitrate = CalVbrMaxKBitRate(video_width_, video_height_); NT_PB_U3D_SetSwVBRMode(pusher_handle_, is_enable_vbr, video_quality, vbr_max_bitrate); //NT_PB_U3D_SetSWVideoEncoderSpeed(pusher_handle_, 2); } } NT_PB_U3D_SetAudioCodecType(pusher_handle_, 1); NT_PB_U3D_SetFPS(pusher_handle_, 25); NT_PB_U3D_SetGopInterval(pusher_handle_, 25*2); //NT_PB_U3D_SetSWVideoBitRate(pusher_handle_, 600, 1200); }
ClosePusher()
private void ClosePusher() { if (texture_ != null) { UnityEngine.Object.Destroy(texture_); texture_ = null; } int flag = NT_PB_U3D_StopPublisher(pusher_handle_); if (flag == DANIULIVE_RETURN_OK) { Debug.Log("停止成功.."); } else { Debug.LogError("停止失败.."); } flag = NT_PB_U3D_Close(pusher_handle_); if (flag == DANIULIVE_RETURN_OK) { Debug.Log("关闭成功.."); } else { Debug.LogError("关闭失败.."); } pusher_handle_ = 0; NT_PB_U3D_UnInit(); is_running = false; }
为了便于测试，Update()刷新下当前时间：
private void Update() { //获取当前时间 hour = DateTime.Now.Hour; minute = DateTime.Now.Minute; millisecond = DateTime.Now.Millisecond; second = DateTime.Now.Second; year = DateTime.Now.Year; month = DateTime.Now.Month; day = DateTime.Now.Day; GameObject.Find("Canvas/Panel/LableText").GetComponent<Text>().text = string.Format("{0:D2}:{1:D2}:{2:D2}:{3:D2} " + "{4:D4}/{5:D2}/{6:D2}", hour, minute, second, millisecond, year, month, day); }
相关Event处理
public void onNTSmartEvent(string param) { if (!param.Contains(",")) { Debug.Log("[onNTSmartEvent] android传递参数错误"); return; } string[] strs = param.Split(','); string player_handle =strs[0]; string code = strs[1]; string param1 = strs[2]; string param2 = strs[3]; string param3 = strs[4]; string param4 = strs[5]; Debug.Log("[onNTSmartEvent] code: 0x" + Convert.ToString(Convert.ToInt32(code), 16)); String publisher_event = ""; switch (Convert.ToInt32(code)) { case EVENTID.EVENT_DANIULIVE_ERC_PUBLISHER_STARTED: publisher_event = "开始.."; break; case EVENTID.EVENT_DANIULIVE_ERC_PUBLISHER_CONNECTING: publisher_event = "连接中.."; break; case EVENTID.EVENT_DANIULIVE_ERC_PUBLISHER_CONNECTION_FAILED: publisher_event = "连接失败.."; break; case EVENTID.EVENT_DANIULIVE_ERC_PUBLISHER_CONNECTED: publisher_event = "连接成功.."; break; case EVENTID.EVENT_DANIULIVE_ERC_PUBLISHER_DISCONNECTED: publisher_event = "连接断开.."; break; case EVENTID.EVENT_DANIULIVE_ERC_PUBLISHER_STOP: publisher_event = "关闭.."; break; case EVENTID.EVENT_DANIULIVE_ERC_PUBLISHER_RECORDER_START_NEW_FILE: publisher_event = "开始一个新的录像文件 : " + param3; break; case EVENTID.EVENT_DANIULIVE_ERC_PUBLISHER_ONE_RECORDER_FILE_FINISHED: publisher_event = "已生成一个录像文件 : " + param3; break; case EVENTID.EVENT_DANIULIVE_ERC_PUBLISHER_SEND_DELAY: publisher_event = "发送时延: " + param1 + " 帧数:" + param2; break; case EVENTID.EVENT_DANIULIVE_ERC_PUBLISHER_CAPTURE_IMAGE: publisher_event = "快照: " + param1 + " 路径：" + param3; if (Convert.ToInt32(param1) == 0) { publisher_event = publisher_event + "截取快照成功.."; } else { publisher_event = publisher_event + "截取快照失败.."; } break; case EVENTID.EVENT_DANIULIVE_ERC_PUBLISHER_RTSP_URL: publisher_event = "RTSP服务URL: " + param3; break; case EVENTID.EVENT_DANIULIVE_ERC_PUSH_RTSP_SERVER_RESPONSE_STATUS_CODE: publisher_event = "RTSP status code received, codeID: " + param1 + ", RTSP URL: " + param3; break; case EVENTID.EVENT_DANIULIVE_ERC_PUSH_RTSP_SERVER_NOT_SUPPORT: publisher_event = "服务器不支持RTSP推送, 推送的RTSP URL: " + param3; break; } Debug.Log(publisher_event); }
总结
通过以上流程，可以实现Unity环境下屏幕或摄像机数据，毫秒级体验的RTMP推送和播放，感兴趣的开发者可酌情参考。
