Android平台轻量级RTSP服务模块技术接入说明

​

为满足内网无纸化/电子教室等内网超低延迟需求，避免让用户配置单独的服务器，大牛直播SDK在推送端发布了轻量级RTSP服务SDK。

轻量级RTSP服务解决的核心痛点是避免用户或者开发者单独部署RTSP或者RTMP服务，实现本地的音视频数据（如摄像头、麦克风），编码后，汇聚到内置RTSP服务，对外提供可供拉流的RTSP URL，轻量级RTSP服务，适用于内网环境下，对并发要求不高的场景，支持H.264/H.265，支持RTSP鉴权、单播、组播模式，考虑到单个服务承载能力，我们支持同时创建多个RTSP服务，并支持获取当前RTSP服务会话连接数。

轻量级RTSP服务数据源，支持编码前、编码后数据对接：

• 编码前数据（目前支持的有YV12/NV21/NV12/I420/RGB24/RGBA32/RGB565等数据类型）；
• 编码后数据（如无人机等264/HEVC数据，或者本地解析的MP4音视频数据）；
• 拉取RTSP或RTMP流并注入轻量级RTSP服务模块，组合形成内置RTSP网关模块。

技术对接

 系统要求

• SDK支持Android5.1及以上版本；
• 支持的CPU架构：armv7, arm64, x86, x86_64。

准备工作

• 确保SmartPublisherJniV2.java放到com.daniulive.smartpublisher包名下(可在其他包名下调用)；
• smartavengine.jar加入到工程；
• 拷贝libSmartPublisher.so到工程；
• AndroidManifast.xml添加相关权限：

<uses-permission android:name="android.permission.CAMERA"/>
<uses-feature android:name="android.hardware.camera.autofocus" />
<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />
<uses-permission android:name="android.permission.WAKE_LOCK" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE" />
<uses-permission android:name="android.permission.VIBRATE" />

• Load相关so：

static {  
    System.loadLibrary("SmartPublisher");
}

• build.gradle配置32/64位库：

splits {
    abi {
        enable true
        reset()
        // Specifies a list of ABIs that Gradle should create APKs for
        include 'armeabi-v7a', 'arm64-v8a', 'x86', 'x86_64' //select ABIs to build APKs for
        // Specify that we do not want to also generate a universal APK that includes all ABIs
        universalApk true
    }
}

• 如需集成到自己系统测试，请用大牛直播SDK的app name，授权版按照授权app name正常使用即可；
• 如何改app-name，strings.xml做以下修改：

<string name="app_name">SmartPublisherSDKDemo</string>

接口设计

Android内置轻量级RTSP服务SDK接口详解
调用描述	接口	接口描述
SmartRTSPServerSDK
初始化RTSP Server	InitRtspServer	Init rtsp server(和UnInitRtspServer配对使用，即便是启动多个RTSP服务，也只需调用一次InitRtspServer，请确保在OpenRtspServer之前调用)
创建一个rtsp server	OpenRtspServer	创建一个rtsp server，返回rtsp server句柄
设置端口	SetRtspServerPort	设置rtsp server 监听端口, 在StartRtspServer之前必须要设置端口
设置鉴权用户名、密码	SetRtspServerUserNamePassword	设置rtsp server 鉴权用户名和密码, 这个可以不设置，只有需要鉴权的再设置
获取rtsp server当前会话数	GetRtspServerClientSessionNumbers	获取rtsp server当前的客户会话数, 这个接口必须在StartRtspServer之后再调用
启动rtsp server	StartRtspServer	启动rtsp server
停止rtsp server	StopRtspServer	停止rtsp server
关闭rtsp server	CloseRtspServer	关闭rtsp server
UnInit rtsp server	UnInitRtspServer	UnInit rtsp server(和InitRtspServer配对使用，即便是启动多个RTSP服务，也只需调用一次UnInitRtspServer)
SmartRTSPServerSDK供Publisher调用的接口
设置rtsp的流名称	SetRtspStreamName	设置rtsp的流名称
给要发布的rtsp流设置rtsp server	AddRtspStreamServer	给要发布的rtsp流设置rtsp server, 一个流可以发布到多个rtsp server上，rtsp server的创建启动请参考OpenRtspServer和StartRtspServer接口
清除设置的rtsp server	ClearRtspStreamServer	清除设置的rtsp server
启动rtsp流	StartRtspStream	启动rtsp流
停止rtsp流	StopRtspStream	停止rtsp流

功能支持

• ****​[视频格式]H.264/H.265(Android H.265硬编码)；
•  [音频格式]G.711 A律、AAC；
• 协议：RTSP；
•  [音量调节]Android平台采集端支持实时音量调节；
•  [H.264硬编码]支持H.264特定机型硬编码；
•  [H.265硬编码]支持H.265特定机型硬编码；
• [音视频]支持纯音频/纯视频/音视频；
• [摄像头]支持采集过程中，前后摄像头实时切换；
• 支持帧率、关键帧间隔(GOP)、码率(bit-rate)设置；
• [实时水印]支持动态文字水印、png水印；
• [实时快照]支持实时快照；
• [降噪]支持环境音、手机干扰等引起的噪音降噪处理、自动增益、VAD检测；
• [外部编码前视频数据对接]支持YUV数据对接；
• [外部编码前音频数据对接]支持PCM对接；
• [外部编码后视频数据对接]支持外部H.264、H.265数据对接；
• [外部编码后音频数据对接]外部AAC数据对接；
• [扩展录像功能]支持和录像SDK组合使用，录像相关功能。​
• 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Android 5.1及以上版本。

接口调用详解

本文以大牛直播SDK Android平台Camera2Demo为例，启动RTSP服务、发布RTSP流之前，可以先选择视频分辨率、软编还是硬编码，音频是PCMA还是AAC编码等基础设置，其他参数的设置，可以参考下面InitAndSetConfig()。

以Android平台Camera2对接为例，先初始化RTSP Server：

/*
 * MainActivity.java
 * Author: daniusdk.com
 */
@Override
protected void onCreate(Bundle savedInstanceState) {
	super.onCreate(savedInstanceState);
	setContentView(R.layout.activity_main);
	
	...

	context_ = this.getApplicationContext();
	
	libPublisher = new SmartPublisherJniV2();

	libPublisher.InitRtspServer(context_);      //和UnInitRtspServer配对使用，即便是启动多个RTSP服务，也只需调用一次InitRtspServer，请确保在OpenRtspServer之前调用
}

启动、停止RTSP服务：

//启动/停止RTSP服务
class ButtonRtspServiceListener implements View.OnClickListener {
	public void onClick(View v) {
		if (isRTSPServiceRunning) {
			stopRtspService();

			btnRtspService.setText("启动RTSP服务");
			btnRtspPublisher.setEnabled(false);

			isRTSPServiceRunning = false;
			return;
		}

		Log.i(TAG, "onClick start rtsp service..");

		rtsp_handle_ = libPublisher.OpenRtspServer(0);

		if (rtsp_handle_ == 0) {
			Log.e(TAG, "创建rtsp server实例失败! 请检查SDK有效性");
		} else {
			int port = 8554;
			if (libPublisher.SetRtspServerPort(rtsp_handle_, port) != 0) {
				libPublisher.CloseRtspServer(rtsp_handle_);
				rtsp_handle_ = 0;
				Log.e(TAG, "创建rtsp server端口失败! 请检查端口是否重复或者端口不在范围内!");
			}

			if (libPublisher.StartRtspServer(rtsp_handle_, 0) == 0) {
				Log.i(TAG, "启动rtsp server 成功!");
			} else {
				libPublisher.CloseRtspServer(rtsp_handle_);
				rtsp_handle_ = 0;
				Log.e(TAG, "启动rtsp server失败! 请检查设置的端口是否被占用!");
			}

			btnRtspService.setText("停止RTSP服务");
			btnRtspPublisher.setEnabled(true);

			isRTSPServiceRunning = true;
		}
	}
}

stopRtspService()实现如下：

//停止RTSP服务
private void stopRtspService() {
	if(!isRTSPServiceRunning)
	{
		return;
	}
	if (libPublisher != null && rtsp_handle_ != 0) {
		libPublisher.StopRtspServer(rtsp_handle_);
		libPublisher.CloseRtspServer(rtsp_handle_);
		rtsp_handle_ = 0;
	}
}

发布、停止RTSP流：

//发布/停止RTSP流
class ButtonRtspPublisherListener implements View.OnClickListener {
	public void onClick(View v) {
		if (stream_publisher_.is_rtsp_publishing()) {
			stopRtspPublisher();

			btnRtspPublisher.setText("发布RTSP流");
			btnGetRtspSessionNumbers.setEnabled(false);
			btnRtspService.setEnabled(true);
			return;
		}

		Log.i(TAG, "onClick start rtsp publisher..");

		InitAndSetConfig();

		String rtsp_stream_name = "stream1";
		stream_publisher_.SetRtspStreamName(rtsp_stream_name);
		stream_publisher_.ClearRtspStreamServer();

		stream_publisher_.AddRtspStreamServer(rtsp_handle_);

		if (!stream_publisher_.StartRtspStream()) {
			stream_publisher_.try_release();
			Log.e(TAG, "调用发布rtsp流接口失败!");
			return;
		}

		startAudioRecorder();
		startLayerPostThread();

		btnRtspPublisher.setText("停止RTSP流");
		btnGetRtspSessionNumbers.setEnabled(true);
		btnRtspService.setEnabled(false);
	}
}

stopRtspPublisher()实现如下：

//停止发布RTSP流
private void stopRtspPublisher() {
	stream_publisher_.StopRtspStream();
	stream_publisher_.try_release();

	if (!stream_publisher_.is_publishing())
		stopAudioRecorder();
}

其中，InitAndSetConfig()实现如下，通过调研SmartPublisherOpen()接口，生成推送实例句柄。

/*
 * MainActivity.java
 * Author: daniusdk.com
 */
private void InitAndSetConfig() {
	if (null == libPublisher)
		return;

	if (!stream_publisher_.empty())
		return;

	Log.i(TAG, "InitAndSetConfig video width: " + video_width_ + ", height" + video_height_ + " imageRotationDegree:" + cameraImageRotationDegree_);

	int audio_opt = 1;
	long handle = libPublisher.SmartPublisherOpen(context_, audio_opt, 3,  video_width_, video_height_);
	if (0==handle) {
		Log.e(TAG, "sdk open failed!");
		return;
	}

	Log.i(TAG, "publisherHandle=" + handle);

	int fps = 25;
	int gop = fps * 3;

	initialize_publisher(libPublisher, handle, video_width_, video_height_, fps, gop);

	stream_publisher_.set(libPublisher, handle);
}

对应的initialize_publisher()实现如下，设置软硬编码、帧率、关键帧间隔等。

private boolean initialize_publisher(SmartPublisherJniV2 lib_publisher, long handle, int width, int height, int fps, int gop) {
	if (null == lib_publisher) {
		Log.e(TAG, "initialize_publisher lib_publisher is null");
		return false;
	}

	if (0 == handle) {
		Log.e(TAG, "initialize_publisher handle is 0");
		return false;
	}

	if (videoEncodeType == 1) {
		int kbps = LibPublisherWrapper.estimate_video_hardware_kbps(width, height, fps, true);
		Log.i(TAG, "h264HWKbps: " + kbps);
		int isSupportH264HWEncoder = lib_publisher.SetSmartPublisherVideoHWEncoder(handle, kbps);
		if (isSupportH264HWEncoder == 0) {
			lib_publisher.SetNativeMediaNDK(handle, 0);
			lib_publisher.SetVideoHWEncoderBitrateMode(handle, 1); // 0:CQ, 1:VBR, 2:CBR
			lib_publisher.SetVideoHWEncoderQuality(handle, 39);
			lib_publisher.SetAVCHWEncoderProfile(handle, 0x08); // 0x01: Baseline, 0x02: Main, 0x08: High

			// lib_publisher.SetAVCHWEncoderLevel(handle, 0x200); // Level 3.1
			// lib_publisher.SetAVCHWEncoderLevel(handle, 0x400); // Level 3.2
			// lib_publisher.SetAVCHWEncoderLevel(handle, 0x800); // Level 4
			lib_publisher.SetAVCHWEncoderLevel(handle, 0x1000); // Level 4.1 多数情况下,这个够用了
			//lib_publisher.SetAVCHWEncoderLevel(handle, 0x2000); // Level 4.2

			// lib_publisher.SetVideoHWEncoderMaxBitrate(handle, ((long)h264HWKbps)*1300);

			Log.i(TAG, "Great, it supports h.264 hardware encoder!");
		}
	} else if (videoEncodeType == 2) {
		int kbps = LibPublisherWrapper.estimate_video_hardware_kbps(width, height, fps, false);
		Log.i(TAG, "hevcHWKbps: " + kbps);
		int isSupportHevcHWEncoder = lib_publisher.SetSmartPublisherVideoHevcHWEncoder(handle, kbps);
		if (isSupportHevcHWEncoder == 0) {
			lib_publisher.SetNativeMediaNDK(handle, 0);
			lib_publisher.SetVideoHWEncoderBitrateMode(handle, 1); // 0:CQ, 1:VBR, 2:CBR
			lib_publisher.SetVideoHWEncoderQuality(handle, 39);

			// libPublisher.SetVideoHWEncoderMaxBitrate(handle, ((long)hevcHWKbps)*1200);

			Log.i(TAG, "Great, it supports hevc hardware encoder!");
		}
	}

	boolean is_sw_vbr_mode = true;
	//H.264 software encoder
	if (is_sw_vbr_mode) {
		int is_enable_vbr = 1;
		int video_quality = LibPublisherWrapper.estimate_video_software_quality(width, height, true);
		int vbr_max_kbps = LibPublisherWrapper.estimate_video_vbr_max_kbps(width, height, fps);
		lib_publisher.SmartPublisherSetSwVBRMode(handle, is_enable_vbr, video_quality, vbr_max_kbps);
	}

	if (is_pcma_) {
		lib_publisher.SmartPublisherSetAudioCodecType(handle, 3);
	} else {
		lib_publisher.SmartPublisherSetAudioCodecType(handle, 1);
	}

	lib_publisher.SetSmartPublisherEventCallbackV2(handle, new EventHandlerPublisherV2().set(handler_, record_executor_));

	lib_publisher.SmartPublisherSetSWVideoEncoderProfile(handle, 3);

	lib_publisher.SmartPublisherSetSWVideoEncoderSpeed(handle, 2);

	lib_publisher.SmartPublisherSetGopInterval(handle, gop);

	lib_publisher.SmartPublisherSetFPS(handle, fps);

	// lib_publisher.SmartPublisherSetSWVideoBitRate(handle, 600, 1200);

	boolean is_noise_suppression = true;
	lib_publisher.SmartPublisherSetNoiseSuppression(handle, is_noise_suppression ? 1 : 0);

	boolean is_agc = false;
	lib_publisher.SmartPublisherSetAGC(handle, is_agc ? 1 : 0);

	int echo_cancel_delay = 0;
	lib_publisher.SmartPublisherSetEchoCancellation(handle, 1, echo_cancel_delay);

	return true;
}

发布RTSP流成功后，会回调上来可供拉流的RTSP URL：

private static class EventHandlerPublisherV2 implements NTSmartEventCallbackV2 {
	@Override
	public void onNTSmartEventCallbackV2(long handle, int id, long param1, long param2, String param3, String param4, Object param5) {

		switch (id) {
			...
			case NTSmartEventID.EVENT_DANIULIVE_ERC_PUBLISHER_RTSP_URL:
				publisher_event = "RTSP服务URL: " + param3;
				break;
		}
	}
}

获取RTSP Session会话数：

//获取RTSP会话数
class ButtonGetRtspSessionNumbersListener implements View.OnClickListener {
	public void onClick(View v) {
		if (libPublisher != null && rtsp_handle_ != 0) {
			int session_numbers = libPublisher.GetRtspServerClientSessionNumbers(rtsp_handle_);

			Log.i(TAG, "GetRtspSessionNumbers: " + session_numbers);

			PopRtspSessionNumberDialog(session_numbers);
		}
	}
}

//当前RTSP会话数弹出框
private void PopRtspSessionNumberDialog(int session_numbers) {
	final EditText inputUrlTxt = new EditText(this);
	inputUrlTxt.setFocusable(true);
	inputUrlTxt.setEnabled(false);

	String session_numbers_tag = "RTSP服务当前客户会话数: " + session_numbers;
	inputUrlTxt.setText(session_numbers_tag);

	AlertDialog.Builder builderUrl = new AlertDialog.Builder(this);
	builderUrl
			.setTitle("内置RTSP服务")
			.setView(inputUrlTxt).setNegativeButton("确定", null);
	builderUrl.show();
}

数据投递如下（以Camera2采集为例，如果是其他视频格式，也可以正常对接）：

@Override
public void onCameraImageData(Image image) {
	....
	for (LibPublisherWrapper i : publisher_array_)
		i.PostLayerImageYUV420888ByteBuffer(0, 0, 0,
			planes[0].getBuffer(), y_offset, planes[0].getRowStride(),
			planes[1].getBuffer(), u_offset, planes[1].getRowStride(),
			planes[2].getBuffer(), v_offset, planes[2].getRowStride(), planes[1].getPixelStride(),
			w, h, 0, 0,
			scale_w, scale_h, scale_filter_mode, rotation_degree);

}

音频采集投递设计如下：

void startAudioRecorder() {
	if (audio_recorder_ != null)
		return;

	audio_recorder_ = new NTAudioRecordV2(this);

	Log.i(TAG, "startAudioRecorder call audio_recorder_.start()+++...");

	audio_recorder_callback_ = new NTAudioRecordV2CallbackImpl(stream_publisher_, null);

	audio_recorder_.AddCallback(audio_recorder_callback_);

	if (!audio_recorder_.Start(is_pcma_ ? 8000 : 44100, 1) ) {
		audio_recorder_.RemoveCallback(audio_recorder_callback_);
		audio_recorder_callback_ = null;

		audio_recorder_ = null;

		Log.e(TAG, "startAudioRecorder start failed.");
	}
	else {
		Log.i(TAG, "startAudioRecorder call audio_recorder_.start() OK---...");
	}
}

void stopAudioRecorder() {
	if (null == audio_recorder_)
		return;

	Log.i(TAG, "stopAudioRecorder+++");

	audio_recorder_.Stop();

	if (audio_recorder_callback_ != null) {
		audio_recorder_.RemoveCallback(audio_recorder_callback_);
		audio_recorder_callback_ = null;
	}

	audio_recorder_ = null;

	Log.i(TAG, "stopAudioRecorder---");
}

回调Audio数据的地方，直接投递出去：

private static class NTAudioRecordV2CallbackImpl implements NTAudioRecordV2Callback {
	private WeakReference<LibPublisherWrapper> publisher_0_;
	private WeakReference<LibPublisherWrapper> publisher_1_;

	public NTAudioRecordV2CallbackImpl(LibPublisherWrapper publisher_0) {
		if (publisher_0 != null)
			publisher_0_ = new WeakReference<>(publisher_0);
	}

	private final LibPublisherWrapper get_publisher_0() {
		if (publisher_0_ !=null)
			return publisher_0_.get();

		return null;
	}

	@Override
	public void onNTAudioRecordV2Frame(ByteBuffer data, int size, int sampleRate, int channel, int per_channel_sample_number) {

		LibPublisherWrapper publisher_0 = get_publisher_0();
		if (publisher_0 != null)
			publisher_0.OnPCMData(data, size, sampleRate, channel, per_channel_sample_number);
	}
}

onDestroy() 的时候，调研UnInitRtspServer()即可：

@Override
protected void onDestroy() {
	Log.i(TAG, "activity destory!");

	stopAudioRecorder();

	stopRtspPublisher();
	stopRtspService();
	isRTSPServiceRunning = false;

	stream_publisher_.release();

	if (libPublisher != null)
		libPublisher.UnInitRtspServer();      //如已启用内置服务功能(InitRtspServer)，调用UnInitRtspServer, 注意，即便是启动多个RTSP服务，也只需调用UnInitRtspServer一次

	stopLayerPostThread();

	if (camera2Helper != null) {
		camera2Helper.release();
	}

	super.onDestroy();
}

总结

以上是Android平台轻量级RTSP服务模块详细的对接说明，除了可以对接编码前音视频数据外，模块还支持对接编码后音视频数据，并实现本地录像、快照等功能组合使用。感兴趣的开发者，可以单独跟我们探讨。

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