技术背景
我们在做Linux平台x86_64架构或aarch64架构的推送模块的时候,有公司提出这样的技术需求,希望在Linux平台,实现轻量级RTSP服务,实现对摄像头或屏幕对外RTSP拉流,同步到大屏上去。
技术实现
废话不多说,直接上代码,先调用start_rtsp_server()指定端口号,启动RTSP服务。
LogInit();NT_SmartPublisherSDKAPI push_api;if (!PushSDKInit(push_api)){XDestroyWindow(display, sub_wid);XDestroyWindow(display, main_wid);XCloseDisplay(display);return 0;}// auto rtsp_server_handle = start_rtsp_server(&push_api, 8554, "test", "12345");auto rtsp_server_handle = start_rtsp_server(&push_api, 8554, "", "");if (nullptr == rtsp_server_handle) {fprintf(stderr, "start_rtsp_server failed.\n");XDestroyWindow(display, sub_wid);XDestroyWindow(display, main_wid);XCloseDisplay(display);push_api.UnInit();return 0;}auto push_handle = open_config_instance(&push_api, 20);if (nullptr == push_handle) {fprintf(stderr, "open_config_instance failed.\n");XDestroyWindow(display, sub_wid);XDestroyWindow(display, main_wid);XCloseDisplay(display);stop_rtsp_server(&push_api, rtsp_server_handle);push_api.UnInit();return 0;}
PushSDKInit()实现如下:
/** publisherdemo.cpp* Author: daniusdk.com*/bool PushSDKInit(NT_SmartPublisherSDKAPI& push_api){memset(&push_api, 0, sizeof(push_api));NT_GetSmartPublisherSDKAPI(&push_api);auto ret = push_api.Init(0, nullptr);if (NT_ERC_OK != ret){fprintf(stderr, "push_api.Init failed!\n");return false;}else{fprintf(stdout, "push_api.Init ok!\n");}return true;}
启动RTSP服务对应的代码如下:
NT_HANDLE start_rtsp_server(NT_SmartPublisherSDKAPI* push_api, int port, std::string user_name, std::string password) {NT_HANDLE rtsp_server_handle = nullptr;if (NT_ERC_OK != push_api->OpenRtspServer(&rtsp_server_handle, 0)) {fprintf(stderr, "OpenRtspServer failed\n");return nullptr;}if (nullptr == rtsp_server_handle) {fprintf(stderr, "rtsp_server_handle is null\n");return nullptr;}if (NT_ERC_OK != push_api->SetRtspServerPort(rtsp_server_handle, port)) {push_api->CloseRtspServer(rtsp_server_handle);return nullptr;}if (!user_name.empty() && !password.empty())push_api->SetRtspServerUserNamePassword(rtsp_server_handle, user_name.c_str(), password.c_str());if (NT_ERC_OK == push_api->StartRtspServer(rtsp_server_handle, 0))return rtsp_server_handle;fprintf(stderr, "StartRtspServer failed\n");push_api->CloseRtspServer(rtsp_server_handle);return nullptr;}
open_config_instance()实现如下,可以获取摄像头或屏幕数据,并做基础的编码等参数配置:
NT_HANDLE open_config_instance(NT_SmartPublisherSDKAPI* push_api, int dst_fps) {NT_INT32 pulse_device_number = 0;if (NT_ERC_OK == push_api->GetAuidoInputDeviceNumber(2, &pulse_device_number)){fprintf(stdout, "[daniusdk.com]Pulse device num:%d\n", pulse_device_number);char device_name[512];for (auto i = 0; i < pulse_device_number; ++i){if (NT_ERC_OK == push_api->GetAuidoInputDeviceName(2, i, device_name, 512)){fprintf(stdout, "[daniusdk.com]index:%d name:%s\n", i, device_name);}}}NT_INT32 alsa_device_number = 0;if (pulse_device_number < 1){if (NT_ERC_OK == push_api->GetAuidoInputDeviceNumber(1, &alsa_device_number)){fprintf(stdout, "Alsa device num:%d\n", alsa_device_number);char device_name[512];for (auto i = 0; i < alsa_device_number; ++i){if (NT_ERC_OK == push_api->GetAuidoInputDeviceName(1, i, device_name, 512)){fprintf(stdout, "[daniusdk.com]index:%d name:%s\n", i, device_name);}}}}NT_INT32 capture_speaker_flag = 0;if (NT_ERC_OK == push_api->IsCanCaptureSpeaker(2, &capture_speaker_flag)){if (capture_speaker_flag)fprintf(stdout, "[daniusdk.com]Support speaker capture\n");elsefprintf(stdout, "[daniusdk.com]UnSupport speaker capture\n");}NT_INT32 is_support_window_capture = 0;if (NT_ERC_OK == push_api->IsCaptureXWindowSupported(NULL, &is_support_window_capture)){if (is_support_window_capture)fprintf(stdout, "[daniusdk.com]Support window capture\n");elsefprintf(stdout, "[daniusdk.com]UnSupport window capture\n");}if (is_support_window_capture){NT_INT32 win_count = 0;if (NT_ERC_OK == push_api->UpdateCaptureXWindowList(NULL, &win_count) && win_count > 0){fprintf(stdout, "X Capture Winows list++\n");for (auto i = 0; i < win_count; ++i){NT_UINT64 wid;char title[512];if (NT_ERC_OK == push_api->GetCaptureXWindowInfo(i, &wid, title, sizeof(title) / sizeof(char))){x_win_list.push_back(wid);fprintf(stdout, "wid:%llu, title:%s\n", wid, title);}}fprintf(stdout, "[daniusdk.com]X Capture Winows list--\n");}}std::vector<CameraInfo> cameras;GetCameraInfo(push_api, cameras);if (!cameras.empty()){fprintf(stdout, "cameras count:%d\n", (int)cameras.size());for (const auto& c : cameras){fprintf(stdout, "camera name:%s, id:%s, cap_num:%d\n", c.name_.c_str(), c.id_.c_str(), (int)c.capabilities_.size());for (const auto& i : c.capabilities_){fprintf(stdout, "[daniusdk.com]cap w:%d, h:%d, fps:%d\n", i.width_, i.height_, i.max_frame_rate_);}}}NT_UINT32 auido_option = NT_PB_E_AUDIO_OPTION_NO_AUDIO;if (pulse_device_number > 0 || alsa_device_number > 0){auido_option = NT_PB_E_AUDIO_OPTION_CAPTURE_MIC;}else if (capture_speaker_flag){auido_option = NT_PB_E_AUDIO_OPTION_CAPTURE_SPEAKER;}//auido_option = NT_PB_E_AUDIO_OPTION_CAPTURE_MIC_SPEAKER_MIXER;NT_UINT32 video_option = NT_PB_E_VIDEO_OPTION_SCREEN;if (!cameras.empty()){video_option = NT_PB_E_VIDEO_OPTION_CAMERA;}else if (is_support_window_capture){video_option = NT_PB_E_VIDEO_OPTION_WINDOW;}// video_option = NT_PB_E_VIDEO_OPTION_LAYER;//video_option = NT_PB_E_VIDEO_OPTION_NO_VIDEO;NT_HANDLE push_handle = nullptr;//if (NT_ERC_OK != push_api->Open(&push_handle, NT_PB_E_VIDEO_OPTION_LAYER, NT_PB_E_AUDIO_OPTION_CAPTURE_SPEAKER, 0, NULL))if (NT_ERC_OK != push_api->Open(&push_handle, video_option, auido_option, 0, NULL)){return nullptr;}push_api->SetEventCallBack(push_handle, nullptr, OnSDKEventHandle);//push_api->SetXDisplayName(push_handle, ":0");//push_api->SetXDisplayName(push_handle, NULL);// 视频层配置方式if (NT_PB_E_VIDEO_OPTION_LAYER == video_option){std::vector<std::shared_ptr<nt_pb_sdk::layer_conf_wrapper_base> > layer_confs;auto index = 0;第0层填充RGBA矩形, 目的是保证帧率, 颜色就填充全黑auto rgba_layer_c0 = std::make_shared<nt_pb_sdk::RGBARectangleLayerConfigWrapper>(index++, true, 0, 0, 1280, 720);rgba_layer_c0->conf_.red_ = 200;rgba_layer_c0->conf_.green_ = 200;rgba_layer_c0->conf_.blue_ = 200;rgba_layer_c0->conf_.alpha_ = 255;layer_confs.push_back(rgba_layer_c0);// 第一层为桌面层//auto screen_layer_c1 = std::make_shared<nt_pb_sdk::ScreenLayerConfigWrapper>(index++, true, 0, 0, 1280, 720);//screen_layer_c1->conf_.scale_filter_mode_ = 3;//layer_confs.push_back(screen_layer_c1);第一层为窗口if (!x_win_list.empty()){auto window_layer_c1 = std::make_shared<nt_pb_sdk::WindowLayerConfigWrapper>(index++, true, 0, 0, 640, 360);window_layer_c1->conf_.xwindow_ = x_win_list.back();layer_confs.push_back(window_layer_c1);}摄像头层if (!cameras.empty()){auto camera_layer_c1 = std::make_shared<nt_pb_sdk::CameraLayerConfigWrapper>(index++, true,640, 0, 640, 360);strcpy(camera_layer_c1->conf_.device_unique_id_, cameras.front().id_.c_str());camera_layer_c1->conf_.is_flip_horizontal_ = 0;camera_layer_c1->conf_.is_flip_vertical_ = 0;camera_layer_c1->conf_.rotate_degress_ = 0;layer_confs.push_back(camera_layer_c1);if (cameras.size() > 1){auto camera_layer_c2 = std::make_shared<nt_pb_sdk::CameraLayerConfigWrapper>(index++, true,640, 0, 320, 240);strcpy(camera_layer_c2->conf_.device_unique_id_, cameras.back().id_.c_str());camera_layer_c2->conf_.is_flip_horizontal_ = 0;camera_layer_c2->conf_.is_flip_vertical_ = 0;camera_layer_c2->conf_.rotate_degress_ = 0;layer_confs.push_back(camera_layer_c2);}}auto image_layer1 = std::make_shared<nt_pb_sdk::ImageLayerConfigWrapper>(index++, true, 650, 120, 324, 300);strcpy(image_layer1->conf_.file_name_utf8_, "./testpng/tca.png");layer_confs.push_back(image_layer1);auto image_layer2 = std::make_shared<nt_pb_sdk::ImageLayerConfigWrapper>(index++, true, 120, 380, 182, 138);strcpy(image_layer2->conf_.file_name_utf8_, "./testpng/t4.png");layer_confs.push_back(image_layer2);std::vector<const NT_PB_LayerBaseConfig* > layer_base_confs;for (const auto& i : layer_confs){layer_base_confs.push_back(i->getBase());}if (NT_ERC_OK != push_api->SetLayersConfig(push_handle, 0, layer_base_confs.data(),layer_base_confs.size(), 0, nullptr)){push_api->Close(push_handle);push_handle = nullptr;return nullptr;}}// push_api->SetScreenClip(push_handle, 0, 0, 1280, 720);if (video_option == NT_PB_E_VIDEO_OPTION_CAMERA){if (!cameras.empty()){push_api->SetVideoCaptureDeviceBaseParameter(push_handle, cameras.front().id_.c_str(),640, 480);//push_api->FlipVerticalCamera(push_handle, 1);//push_api->FlipHorizontalCamera(push_handle, 1);//push_api->RotateCamera(push_handle, 0);}}if (video_option == NT_PB_E_VIDEO_OPTION_WINDOW){if (!x_win_list.empty()){//push_api->SetCaptureXWindow(push_handle, x_win_list[0]);push_api->SetCaptureXWindow(push_handle, x_win_list.back());}}push_api->SetFrameRate(push_handle, dst_fps); // 帧率设置push_api->SetVideoEncoder(push_handle, 0, 1, NT_MEDIA_CODEC_ID_H264, 0);push_api->SetVideoBitRate(push_handle, 2000); // 平均码率2000kbpspush_api->SetVideoQuality(push_handle, 26);push_api->SetVideoMaxBitRate(push_handle, 4000); // 最大码率4000kbps// openh264 配置特定参数push_api->SetVideoEncoderSpecialInt32Option(push_handle, "usage_type", 0); //0是摄像头编码, 1是屏幕编码push_api->SetVideoEncoderSpecialInt32Option(push_handle, "rc_mode", 1); // 0是质量模式, 1是码率模式push_api->SetVideoEncoderSpecialInt32Option(push_handle, "enable_frame_skip", 0); // 0是关闭跳帧, 1是打开跳帧push_api->SetVideoKeyFrameInterval(push_handle, dst_fps * 2); // 关键帧间隔push_api->SetVideoEncoderProfile(push_handle, 3); // H264 highpush_api->SetVideoEncoderSpeed(push_handle, 3); // 编码速度设置到3if (pulse_device_number > 0){push_api->SetAudioInputLayer(push_handle, 2);push_api->SetAuidoInputDeviceId(push_handle, 0);}else if (alsa_device_number > 0){push_api->SetAudioInputLayer(push_handle, 1);push_api->SetAuidoInputDeviceId(push_handle, 0);}push_api->SetEchoCancellation(push_handle, 1, 0);push_api->SetNoiseSuppression(push_handle, 1);push_api->SetAGC(push_handle, 1);push_api->SetVAD(push_handle, 1);push_api->SetInputAudioVolume(push_handle, 0, 1.0);push_api->SetInputAudioVolume(push_handle, 1, 0.2);// 音频配置push_api->SetPublisherAudioCodecType(push_handle, 1);//push_api->SetMute(push_handle, 1);return push_handle;}
发布RTSP流实现如下:
bool start_rtsp_stream(NT_SmartPublisherSDKAPI* push_api, NT_HANDLE rtsp_server_handle, NT_HANDLE handle, const std::string stream_name) {push_api->SetRtspStreamName(handle, stream_name.c_str());push_api->ClearRtspStreamServer(handle);push_api->AddRtspStreamServer(handle, rtsp_server_handle, 0);if (NT_ERC_OK != push_api->StartRtspStream(handle, 0))return false;return true;}
如果需要本地摄像头或者屏幕预览数据,调研预览接口即可:
// 开启预览,也可以不开启, 根据需求来push_api.SetPreviewXWindow(push_handle, "", sub_wid);push_api.StartPreview(push_handle, 0, nullptr);
如需停止:
fprintf(stdout, "StopRtspStream++\n");push_api.StopRtspStream(push_handle);fprintf(stdout, "StopRtspStream--\n");fprintf(stdout, "stop_rtsp_server++\n");stop_rtsp_server(&push_api, rtsp_server_handle);fprintf(stdout, "stop_rtsp_server--\n");push_api.StopPreview(push_handle);// push_api.StopPublisher(push_handle);push_api.Close(push_handle);push_handle = nullptr;XDestroyWindow(display, sub_wid);XDestroyWindow(display, main_wid);XCloseDisplay(display);push_api.UnInit();
总结
Linux平台arm64实现轻量级RTSP服务,目前实现的功能如下:
- 音频编码:AAC;
- 视频编码:H.264;
- 协议:RTSP;
- [音视频]支持纯音频/纯视频/音视频推送;
- 支持X11屏幕采集;
- 支持部分V4L2摄像头设备采集;
- [屏幕/V4L2摄像头]支持帧率、关键帧间隔(GOP)、码率(bit-rate)设置;
- [V4L2摄像头]支持V4L2摄像头设备选择(设备文件名范围:[/dev/video0, /dev/video63])、分辨率设置、帧率设置;
- [V4L2摄像头]支持水平反转、垂直反转、0° 90° 180° 270°旋转;
- [音频]支持基于alsa-lib接口的音频采集;
- [音频]支持基于libpulse接口采集本机PulseAudio服务音频;
- [预览]支持实时预览; 支持RTSP端口设置;
- 支持RTSP鉴权用户名、密码设置;
- 支持获取当前RTSP服务会话连接数;
- 支持x64_64架构、aarch64架构(需要glibc-2.21及以上版本的Linux系统, 需要libX11.so.6, 需要GLib–2.0, 需安装 libstdc++.so.6.0.21、GLIBCXX_3.4.21、 CXXABI_1.3.9)。
配合我们的RTSP播放器,可轻松实现150-400ms低延迟体验,感兴趣的开发者,可以单独跟我沟通。