/OBS

Primary LanguageCGNU General Public License v2.0GPL-2.0

obs-studio with Agora SDK

中文: 中文

Build guideline

  • Requirements for using obs-studio for building HQ on windows

    • Cmake of Windows version

    • visual studio 2015(also support vs2013 and vs2017)

    • QT 5.9.2(msvc2015, any version QT adjust to visual studio version) if you need UI

  • Version

    • agora sdk windows version 2.9.0 and above(x86), also support x64.
    • obs studio 21.1b and above(x86), also support x64.

  • Build project with CMake-gui：

    • Start CMake-gui, select source code and project path, then configure

    • Set variables in windows environment:

      • DepsPath

         The path where win32 or win64 is located after decompressing dedependencies2015.zip(dedependencies2013.zip or dedependencies2017.zip). dedependencies2013 not support win64.

      • QTDir

         The path where win32 is loacted after installed QT 5.9.2

      • Uncheck ENABLE_SCRIPTING

      • After configure is ok,then click generate, vs project can be generated.

How to use agora sdk in your own obs studio

In order to use agora sdk in your own obs studio, there's statement about compile and source code.

Initialize Agora Service Settings In Application

You can reference source code in window-basic-main.cpp file(OBSBasic::InitAgoraServiceSettings).

  • agora_video_bitrate

    video bitrate

  • fps

    video frame rate

  • agora_out_cx and agora_out_cy

    video output resolution width and height

  • agora_appid

    agora appid

  • agora_uid

    agora user uid used when calling joinChannel

  • agora_channel

    agora channel used when calling joinChannel

  • enableWebSdkInteroperability

    whether enable web sdk interoperability with windows/ios/android native sdk

How to create win-agora plugin

  • Source code
  • Agora SDK
  • Compile configuration

win-agora plugin source code

  • Create a folder named win-agora in plugins folder of obs studio, the create agora-plugin.cpp file. obs.dll will automatically load all dll in the plugins folder.

  • Include header file obs-module.h, write OBS_DECLARE_MODULE to declare win-agora plugin. Register agora_pcm、agora_yuv、agora_service、agora_output in obs_load_module function. When obs.dll load win-agora.dll plugin, it'll register these plugins.

  • The most important thing for encoder is obs_encoder_info.encode(AgoraPCM_Encode and AgoraYUV_Encode). OBS will call agora sdk api in these two function and send audio and video data to agora sdk. Audio and Video encoders are implemented in agora-pcm-encoder.cpp and agora-yuv-encoder.cpp.

  • Besides configure some information for agora sdk by agora_service, call agora_service member function to use agora sdk api.

  • Add apis in obs.h for agora sdk api, application will call obs api. These new apis will call agora_service member function.agora_service is implemented in agora_service.cpp.

  • agora output is actually a null output.It's used to start or stop agora communication. OBS studio library associated encoder and service with agora output. agora_service is implemented in agora-output.cpp

Agora sdk

Download zip file download.

Decompress zip file,you'll find dll， include and lib folders in sdk.

  • dll copy agora_rtc_sdk.dll and agora_sig_sdk.dll to dependencies2013\win32\bin
  • lib copy agora_rtc_sdk.lib to dependencies2013\win32\bin
  • include Create agora folder in dependencies2013\win32\include, then copy agora header files to here.

Note:If you want to set custom video profile, include IAgoraRtcEngine2.h.

Set compile configurations

  • Create a file FindAgora.cmake for win-agora plugin. It's used to search agora dll that win-agora plugin depends, then set some compile configurations, copy it to CMake\Modules.
  • CMakeLists.txt in win-agora folder is used to compile win-agora source code.
  • Configure agora sdk that win-agora plugin depends in CopyMSVCBins.cmake file. When generating win-agora, copy agora dll to CMake\Modules folders.

Summary

how to use obs studio demo that use agora sdk：

  • Copy win-agora folder in plugins to you own plugins folder.
  • Copy agora dll and lib folder to dependencies2013\win32\bin. Create agora folder in dependencies2013\win32\include, then copy agora header files here.
  • Copy FindAgora.cmake file to CMake\Modules. Copy text including agora in CopyMSVCBins.cmake to you own file CopyMSVCBins.cmake.
  • In files obs.h、obs.cpp、obs-service.h,search agora, copy the source code to to you own corresponding files.

After that, you use CMake to compile obs, then generate vs project.UI is optional, you decide by yourself. How to use win-agora plugin, you can reference demo.

##how add agora sdk api and callback

If you need to call agora sdk api and do something in the callback, add these by yourself. Now I just add several necessary apis and callbacks. Callbacks send signals to the application by signal of obs studio.Some apis, for example, initEngine, joinChannel etc, are encapsulated in win-agora plugin. You don't need to call these apis in the application.

Currently encapsulated apis and callbacks:

apis：

  • setupRemoteVideo
  • addPublishStreamUrl
  • removePublishStreamUrl

callbacks：

  • onJoinChannelSuccess
  • onUserOffline
  • onUserJoined
  • onFirstRemoteVideoDecoded

how to add agora sdk apis

  • In the file obs-service.h，add new member function declaration to obs_service_info
  • In the file agora-service.cpp，Add member function implement for agora_service, the member fucntion will call agora sdk api.
  • In the file obs.h, declare api, the first parameter type of this api is obs_service_t*
  • In the file obs.cpp, implement the api. This api will call new adding member function for agora service.
  • Then the application call new adding api in obs.h .

You can reference setupRemoteVideo, it's implemented in obs_service_agora_setup_remote_video and obs_service_info.setup_agora_remote_video.

how to add agora callbacks

After calling some apis, you'll receive agora callbacks. Sometimes you must first receive callbacks, then you can call other agora apis. For example, after receiving onUserJoined callback, you can call setupRemoteVideo to show remote video.

  • In the file obs-service.c, in constant character array service_signals, add callbacks correspond to signals, including return type and function name.
  • agorartcengine.cpp，agora sdk callback send signal to app, call signal_handler_signal. you can set parameters with calldata structure.

what to do in the application:

  • Call signal_handler_connect, connect new adding service signal to the application callback. Note, these callbacks are static member functions, you need notify the main thread(UI thread) by aaplication message(Signal/Slot of QT).

For example, onUserJoined, add callback：

  • Add "void userJoined()" in service_signals.

  • In the file agorartcengine.cpp, override onUserJoined, set parameter of the callback, then call

       signal_handler_signal(obs_service_get_signal_handler(m_engine.agoraService), "userJoined", &params);

    you'll receive the signal in the aaplication.

  • In the application, associate callback with new signal, call

      signal_handler_connect(obs_service_get_signal_handler(agoraService), "userJoined", AgoraUserJoined, &params);

after receive userJoined signal, it'll call AgoraUserJoined static member function.

  • In the member function AgoraUserJoined, notify main thread by qt signal/slot.

      QMetaObject::invokeMethod(App()->GetMainWindow(), "OnUserJoined", Q_ARG(long long, uid));

Now you can do something in OBSBasic::OnUserJoined*