手机如何制作网站源码,网页平面设计培训班,建设路21号官方网站,滁州新橙科技网站建设许多开发者#xff0c;在做智慧教室同屏、会议同屏之类的方案时#xff0c;基于Andriod平台的采集#xff0c;往往遇到各种各样的问题#xff0c;以下就几个点#xff0c;抛砖引玉#xff1a;
1. 内网环境下#xff0c;组播还是RTMP#xff1f;
回答#xff1a;这个…许多开发者在做智慧教室同屏、会议同屏之类的方案时基于Andriod平台的采集往往遇到各种各样的问题以下就几个点抛砖引玉
1. 内网环境下组播还是RTMP
回答这个问题被无数的开发者问到为此单独写了篇博客论证https://blog.csdn.net/renhui1112/article/details/86741428感兴趣的可以参考下简单来说能RTMP的就RTMP如果真是内网环境下没有并发瓶颈的同屏可以启动内置RTSP服务走单播然后其他终端拉流也不失为一个好的方案。
2. 推送分辨率如何设定或缩放
回答一般来说好多Android设备特别是高分屏拿到的视频原始宽高非常大如果推原始分辨率编码和上行压力大所以一般建议适当缩放比如宽高缩放至2/3缩放一般建议等比例缩放此外缩放宽高建议16字节对齐。
废话不多说上实例代码 private void createScreenEnvironment() {sreenWindowWidth mWindowManager.getDefaultDisplay().getWidth();screenWindowHeight mWindowManager.getDefaultDisplay().getHeight();Log.i(TAG, screenWindowWidth: sreenWindowWidth ,screenWindowHeight: screenWindowHeight);if (sreenWindowWidth 800){if (screenResolution SCREEN_RESOLUTION_STANDARD){scale_rate SCALE_RATE_HALF;sreenWindowWidth align(sreenWindowWidth / 2, 16);screenWindowHeight align(screenWindowHeight / 2, 16);}else if(screenResolution SCREEN_RESOLUTION_LOW){scale_rate SCALE_RATE_TWO_FIFTHS;sreenWindowWidth align(sreenWindowWidth * 2 / 5, 16);}}Log.i(TAG, After adjust mWindowWidth: sreenWindowWidth , mWindowHeight: screenWindowHeight);int pf mWindowManager.getDefaultDisplay().getPixelFormat();Log.i(TAG, display format: pf);DisplayMetrics displayMetrics new DisplayMetrics();mWindowManager.getDefaultDisplay().getMetrics(displayMetrics);mScreenDensity displayMetrics.densityDpi;mImageReader ImageReader.newInstance(sreenWindowWidth,screenWindowHeight, 0x1, 6);mMediaProjectionManager (MediaProjectionManager) getSystemService(Context.MEDIA_PROJECTION_SERVICE);}
3. 横竖屏自动适配
回答因为横竖屏状态下采集的屏幕宽高不一样如果横竖屏切换这个时候需要考虑到横竖屏适配问题确保比如竖屏状态下切换到横屏时推拉流两端可以自动适配横竖屏自动适配编码器需要重启拉流端需要能自动适配宽高变化自动播放。
4. 一定的补帧策略
回答好多人不理解为什么要补帧实际上屏幕采集的时候屏幕不动的话不会一直有数据下去这个时候比较好的做法是保存最后一帧数据设定一定的补帧间隔确保不会因为帧间距太大导致播放端几秒都收不到数据当然如果服务器可以缓存GOP这个问题迎刃而解。
5. 异常网络处理、事件回调机制
回答如果是走RTMP网络抖动或者其他网络异常需要有好重连机制和状态回馈机制。 class EventHandeV2 implements NTSmartEventCallbackV2 {Overridepublic void onNTSmartEventCallbackV2(long handle, int id, long param1, long param2, String param3, String param4, Object param5) {Log.i(TAG, EventHandeV2: handle handle id: id);String publisher_event ;switch (id) {case NTSmartEventID.EVENT_DANIULIVE_ERC_PUBLISHER_STARTED:publisher_event 开始..;break;case NTSmartEventID.EVENT_DANIULIVE_ERC_PUBLISHER_CONNECTING:publisher_event 连接中..;break;case NTSmartEventID.EVENT_DANIULIVE_ERC_PUBLISHER_CONNECTION_FAILED:publisher_event 连接失败..;break;case NTSmartEventID.EVENT_DANIULIVE_ERC_PUBLISHER_CONNECTED:publisher_event 连接成功..;break;case NTSmartEventID.EVENT_DANIULIVE_ERC_PUBLISHER_DISCONNECTED:publisher_event 连接断开..;break;case NTSmartEventID.EVENT_DANIULIVE_ERC_PUBLISHER_STOP:publisher_event 关闭..;break;case NTSmartEventID.EVENT_DANIULIVE_ERC_PUBLISHER_RECORDER_START_NEW_FILE:publisher_event 开始一个新的录像文件 : param3;break;case NTSmartEventID.EVENT_DANIULIVE_ERC_PUBLISHER_ONE_RECORDER_FILE_FINISHED:publisher_event 已生成一个录像文件 : param3;break;case NTSmartEventID.EVENT_DANIULIVE_ERC_PUBLISHER_SEND_DELAY:publisher_event 发送时延: param1 帧数: param2;break;case NTSmartEventID.EVENT_DANIULIVE_ERC_PUBLISHER_CAPTURE_IMAGE:publisher_event 快照: param1 路径 param3;if (param1 0) {publisher_event publisher_event 截取快照成功..;} else {publisher_event publisher_event 截取快照失败..;}break;case NTSmartEventID.EVENT_DANIULIVE_ERC_PUBLISHER_RTSP_URL:publisher_event RTSP服务URL: param3;break;case NTSmartEventID.EVENT_DANIULIVE_ERC_PUSH_RTSP_SERVER_RESPONSE_STATUS_CODE:publisher_event RTSP status code received, codeID: param1 , RTSP URL: param3;break;case NTSmartEventID.EVENT_DANIULIVE_ERC_PUSH_RTSP_SERVER_NOT_SUPPORT:publisher_event 服务器不支持RTSP推送, 推送的RTSP URL: param3;break;}String str 当前回调状态 publisher_event;Log.i(TAG, str);Message message new Message();message.what PUBLISHER_EVENT_MSG;message.obj publisher_event;handler.sendMessage(message);}}
6. 部分屏幕数据采集
回答我们遇到的好多场景下教室端会拿出来3/4的区域用来投递给学生看1/4的区域用来做一些指令等操作这个时候就需要考虑屏幕区域裁剪接口可做如下设计 /*** 投递裁剪过的RGBA数据** param data: RGBA data** param rowStride: stride information** param width: width** param height: height** param clipedLeft: 左; clipedTop: 上; clipedwidth: 裁剪后的宽; clipedHeight: 裁剪后的高; 确保传下去裁剪后的宽、高均为偶数** return {0} if successful*/public native int SmartPublisherOnCaptureVideoClipedRGBAData(long handle, ByteBuffer data, int rowStride, int width, int height, int clipedLeft, int clipedTop, int clipedWidth, int clipedHeight);//实际裁剪比例可酌情自行调整int left 100;int cliped_left 0;int top 0;int cliped_top 0;int cliped_width width_;int cliped_height height_;if(scale_rate SCALE_RATE_HALF){cliped_left left / 2;cliped_top top / 2;//宽度裁剪后展示3/4比例cliped_width (width_ *3)/4;//高度不做裁剪cliped_height height_;}else if(scale_rate SCALE_RATE_TWO_FIFTHS){cliped_left left * 2 / 5;cliped_top top * 2 / 5;//宽度裁剪后展示3/4比例cliped_width (width_ *3)/4;//高度不做裁剪cliped_height height_;}if(cliped_width % 2 ! 0){cliped_width cliped_width 1;}if(cliped_height % 2 ! 0){cliped_height cliped_height 1;}if ( (cliped_left cliped_width) width_){Log.e(TAG, invalid cliped region settings, cliped_left: cliped_left cliped_width: cliped_width width: width_);return;}if ( (cliped_top cliped_height) height_){Log.e(TAG, invalid cliped region settings, cliped_top: cliped_top cliped_height: cliped_height height: height_);return;}//Log.i(TAG, clipLeft: cliped_left clipTop: cliped_top clipWidth: cliped_width clipHeight: cliped_height);libPublisher.SmartPublisherOnCaptureVideoClipedRGBAData(publisherHandle, last_buffer, row_stride_,width_, height_, cliped_left, cliped_top, cliped_width, cliped_height );
7. 文字、图片水印
回答好多场景下同屏者会把公司logo和一定的文字信息展示在推送端这个时候需要考虑到文字和图片水印问题具体可参考如下接口设置 /*** Set Text water-mark(设置文字水印)* * param fontSize: it should be MEDIUM, SMALL, BIG* * param waterPostion: it should be TOPLEFT, TOPRIGHT, BOTTOMLEFT, BOTTOMRIGHT.* * param xPading, yPading: the distance of the original picture.* * pre The interface is only used for setting font water-mark when publishing stream. /pre * * return {0} if successful*/public native int SmartPublisherSetTextWatermark(long handle, String waterText, int isAppendTime, int fontSize, int waterPostion, int xPading, int yPading);/*** Set Text water-mark font file name(设置文字水印字体路径)** param fontFileName: font full file name, e.g: /system/fonts/DroidSansFallback.ttf** return {0} if successful*/public native int SmartPublisherSetTextWatermarkFontFileName(long handle, String fontFileName);/*** Set picture water-mark(设置png图片水印)* * param picPath: the picture working path, e.g: /sdcard/logo.png* * param waterPostion: it should be TOPLEFT, TOPRIGHT, BOTTOMLEFT, BOTTOMRIGHT.* * param picWidth, picHeight: picture width height* * param xPading, yPading: the distance of the original picture.* * pre The interface is only used for setting picture(logo) water-mark when publishing stream, with *.png format /pre * * return {0} if successful*/public native int SmartPublisherSetPictureWatermark(long handle, String picPath, int waterPostion, int picWidth, int picHeight, int xPading, int yPading);
总结其实一个好的同屏系统需要考虑的地方远不止以上几点比如编码参数策略等都需要考量后续有机会再和大家做进一步分享。
