技术背景

在前面的blog，我们发布了Android平台轻量级RTSP服务模块的技术对接说明，好多开发者希望，更黑盒的对接轻量级RTSP服务这块，专注于自身业务逻辑。为此，我们针对Android平台轻量级RTSP服务模块，做了更进一步的封装（LibPublisherWrapper.java）。

技术对接

本文还是以大牛直播SDK Android平台Camera2Demo为例，如果需要测试轻量级RTSP服务模块，分两步：首先启动RTSP服务，RTSP服务启动后，发布RTSP即可，在此之前，可选择设置视频分辨率、软硬编码类型，音频编码类型等，如需关闭轻量级RTSP服务，先停止发布RTSP流，再停止RTSP服务。

onCreate()的时候，调用LibPublisherWrapper的initialize_sdk()：

/*
 * 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();
    LibPublisherWrapper.RTSPServer.initialize_sdk(libPublisher, context_);
}

对应封装代码如下：

public static boolean initialize_sdk(SmartPublisherJniV2 lib_publisher, android.content.Context context) {
    return sdk_context_.initialize(lib_publisher, context);
}

initalize()具体实现如下：

/*
 * LibPublisherWrapper.java
 * Author: daniusdk.com
 */
public boolean initialize(SmartPublisherJniV2 lib_publisher, android.content.Context context) {
    if (initialized_)
        return initialized_result_;
    if (null == lib_publisher)
        return false;
    if (null == context)
        return false;
    synchronized (this) {
        if (initialized_)
            return initialized_result_;
        try {
            int sdk_ret = lib_publisher.InitRtspServer(context);
            if (0 == sdk_ret)
                initialized_result_ = true;
            else {
                initialized_result_ = false;
                Log.e(TAG, "call sdk InitRtspServer failed, ret:" + sdk_ret);
            }
        } catch (Exception e) {
            initialized_result_ = false;
            Log.e(TAG, "call sdk InitRtspServer Exception:", e);
        }
        initialized_ = true;
        return initialized_result_;
    }
}

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 (!rtsp_server_.empty()) {
            rtsp_server_.reset();
            btnRtspService.setText("启动RTSP服务");
            btnRtspPublisher.setEnabled(false);
            return;
        }
        Log.i(TAG, "onClick start rtsp service..");
        int port = 8554;
        String user_name = null;
        String password = null;
        LibPublisherWrapper.RTSPServer.Handle server_handle = LibPublisherWrapper.RTSPServer.create_and_start_server(libPublisher,
                port, user_name, password);
        if (null == server_handle) {
            Log.e(TAG, "启动rtsp server失败! 请检查设置的端口是否被占用!");
            return;
        }
        rtsp_server_.reset(server_handle);
        btnRtspService.setText("停止RTSP服务");
        btnRtspPublisher.setEnabled(true);
    }
}

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_server_.get_native());
        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 (rtsp_server_.is_running()) {
            int session_numbers = rtsp_server_.get_client_session_number();
            Log.i(TAG, "GetRtspSessionNumbers: " + session_numbers);
            PopRtspSessionNumberDialog(session_numbers);
        }
    }
}

对应的Wrapper封装代码如下：

public int get_client_session_number() {
    if (!is_running())
        return 0;
    if (null == lib_publisher_)
        return 0;
    long handle = native_handle_.get();
    if (0 == handle)
        return 0;
    try {
        int ret = lib_publisher_.GetRtspServerClientSessionNumbers(handle);
        return ret;
    } catch (Exception e) {
        Log.e(TAG, "RTSPServer.Handle.get_client_session_number Exception:", e);
        return 0;
    }
}

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，调用deinitialize_sdk()即可：

@Override
protected void onDestroy() {
    Log.i(TAG, "activity destory!");
    stopAudioRecorder();
    stopRtspPublisher();
    stream_publisher_.release();
    rtsp_server_.reset();
    //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
    LibPublisherWrapper.RTSPServer.deinitialize_sdk(libPublisher);
    stopLayerPostThread();
    if (camera2Helper != null) {
        camera2Helper.release();
    }
    super.onDestroy();
}