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"); else fprintf(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"); else fprintf(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2000kbps push_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 high push_api->SetVideoEncoderSpeed(push_handle, 3); // 编码速度设置到3 if (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。