把Android手机变成远程监控摄像头

基本过程是android作为socket客户端将采集到的每一帧图像数据发送出去，PC作为服务器接收并显示每一帧图像实现远程监控。图片如下（后来PC端加了个拍照功能）。。。

 

（PS。刚学android和java不久很多东西还不懂，高手若是知道哪些地方可以继续优化的话还请多多指点下啊）

系统代码如下：
一、android手机客户端
（1）AndroidManifest.xml文件。添加camera和socket权限，并设置了程序开始执行的activity、

xml version = "1.0" encoding = "utf-8" ?>
< manifest xmlns:android = "http://schemas.android.com/apk/res/android"
    package = "org.wanghai.CameraTest"
    android:versionCode = "1"
    android:versionName = "1.0" >

    < uses-sdk android:minSdkVersion = "15" />


        < uses-permission android:name = "android.permission.CAMERA" />
        < uses-feature android:name = "android.hardware.camera" />
        < uses-feature android:name = "android.hardware.camera.autofocus" />
        < uses-permission android:name = "android.permission.INTERNET" />
    < uses-permission android:name = "android.permission.KILL_BACKGROUND_PROCESSES" />
    < uses-permission android:name = "android.permission.RESTART_PACKAGES" />

    < application
        android:icon = "@drawable/ic_launcher"
        android:label = "@string/app_name" >

        < activity
            android:name = ".GetIP"
            android:screenOrientation = "landscape"
            android:label = "@string/app_name" >
            < intent-filter >
                < action android:name = "android.intent.action.MAIN" />
                < category android:name = "android.intent.category.LAUNCHER" />
            intent-filter >
        activity >
        < activity
            android:name = ".CameraTest"
            android:screenOrientation = "landscape"
            android:label = "@string/app_name" >

        activity >

    application >

manifest >

        （2）main.xml 设置surfaceview用于摄像头采集图像的预览
?
xml version = "1.0" encoding = "utf-8" ?>
< LinearLayout xmlns:android = "http://schemas.android.com/apk/res/android"
    android:layout_width = "fill_parent"
    android:layout_height = "fill_parent"
    android:orientation = "vertical" >

   < SurfaceView
        android:id = "@+id/sView"
        android:layout_width = "fill_parent"
        android:layout_height = "fill_parent"
        android:scaleType = "fitCenter" />

LinearLayout >

        （3）login.xml 登录界面，用于输入服务器IP
?
xml version = "1.0" encoding = "utf-8" ?>
< TableLayout xmlns:android = "http://schemas.android.com/apk/res/android"
        android:id = "@+id/loginForm"
        android:orientation = "vertical"
        android:layout_width = "fill_parent"
        android:layout_height = "fill_parent"
        >

< TableRow >
< TextView
        android:layout_width = "fill_parent"
        android:layout_height = "wrap_content"
        android:text = "IP:"
        android:textSize = "10pt"
        />

< EditText
    android:id = "@+id/ipedittext"
        android:layout_width = "fill_parent"
        android:layout_height = "wrap_content"
        android:digits = "0123456789."
        android:hint = "请填写服务器IP"
        android:selectAllOnFocus = "true"
        />
TableRow >

TableLayout >

        （ 4 ）GetIP.java 获得服务器IP后，通过Intent启动CameraTest的activity，ip信息通过Bundle传递
?
public class GetIP  extends Activity {
        String ipname =  null ;
        @Override
    public void onCreate(Bundle savedInstanceState) {
        super .onCreate(savedInstanceState);
        // 设置全屏
        requestWindowFeature(Window.FEATURE_NO_TITLE);
             getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.main);

              final Builder builder =  new AlertDialog.Builder( this );    //定义一个AlertDialog.Builder对象
                builder.setTitle( "登录服务器对话框" );                           // 设置对话框的标题

                //装载/res/layout/login.xml界面布局
                TableLayout loginForm = (TableLayout)getLayoutInflater().inflate( R.layout.login,  null );
                final EditText iptext = (EditText)loginForm.findViewById(R.id.ipedittext);
                builder.setView(loginForm);                               // 设置对话框显示的View对象
                // 为对话框设置一个“登录”按钮
                builder.setPositiveButton( "登录"
                        // 为按钮设置监听器
                        ,  new OnClickListener() {
                                @Override
                                public void onClick(DialogInterface dialog,  int which) {
                                        //此处可执行登录处理
                                        ipname = iptext.getText().toString().trim();
                                        Bundle data =  new Bundle();
                                        data.putString( "ipname" ,ipname);
                                        Intent intent =  new Intent(GetIP. this ,CameraTest. class );
                                        intent.putExtras(data);
                                        startActivity(intent);
                                }
                        });
                // 为对话框设置一个“取消”按钮
                builder.setNegativeButton( "取消"
                        ,   new OnClickListener()
                        {
                                @Override
                                public void onClick(DialogInterface dialog,  int which)
                                {
                                        //取消登录，不做任何事情。
                                        System.exit( 1 );
                                }
                        });
                //创建、并显示对话框
                builder.create().show();
        }
}

        （ 5 ）CameraTest.java 程序主体。设置PreviewCallback后，每当一帧图像数据采集完成后将调用PreviewCallback的onPreviewFrame函数。在这里我们将YUV格式数据转为jpg，再启用线程将数据通过socket发送出去。
?
public class CameraTest  extends Activity {
        SurfaceView sView;
        SurfaceHolder surfaceHolder;
        int screenWidth, screenHeight;
        Camera camera;                     // 定义系统所用的照相机
        boolean isPreview =  false ;         //是否在浏览中
        private String ipname;

        @SuppressWarnings ( "deprecation" )
        @Override
    public void onCreate(Bundle savedInstanceState) {
        super .onCreate(savedInstanceState);
        // 设置全屏
             requestWindowFeature(Window.FEATURE_NO_TITLE);
             getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.main);

        // 获取IP地址
        Intent intent = getIntent();
        Bundle data = intent.getExtras();
        ipname = data.getString( "ipname" );

                screenWidth =  640 ;
                screenHeight =  480 ;
                sView = (SurfaceView) findViewById(R.id.sView);                   // 获取界面中SurfaceView组件
                surfaceHolder = sView.getHolder();                                // 获得SurfaceView的SurfaceHolder

                // 为surfaceHolder添加一个回调监听器
                surfaceHolder.addCallback( new Callback() {
                        @Override
                        public void surfaceChanged(SurfaceHolder holder,  int format,  int width, int height) {
                        }
                        @Override
                        public void surfaceCreated(SurfaceHolder holder) {
                                initCamera();                                             // 打开摄像头
                        }
                        @Override
                        public void surfaceDestroyed(SurfaceHolder holder) {
                                // 如果camera不为null ,释放摄像头
                                if (camera !=  null ) {
                                        if (isPreview)
                                                camera.stopPreview();
                                        camera.release();
                                        camera =  null ;
                                }
                            System.exit( 0 );
                        }
                });
                // 设置该SurfaceView自己不维护缓冲
                surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

    }

    private void initCamera() {
            if (!isPreview) {
                        camera = Camera.open();
                }
                if (camera !=  null && !isPreview) {
                        try {
                                Camera.Parameters parameters = camera.getParameters();
                                parameters.setPreviewSize(screenWidth, screenHeight);     // 设置预览照片的大小
                                parameters.setPreviewFpsRange( 20 , 30 );                     // 每秒显示20~30帧
                                parameters.setPictureFormat(ImageFormat.NV21);            // 设置图片格式
                                parameters.setPictureSize(screenWidth, screenHeight);     // 设置照片的大小
                                //camera.setParameters(parameters);                      // android2.3.3以后不需要此行代码
                                camera.setPreviewDisplay(surfaceHolder);                  // 通过SurfaceView显示取景画面
                        camera.setPreviewCallback( new StreamIt(ipname));          // 设置回调的类
                                camera.startPreview();                                    // 开始预览
                                camera.autoFocus( null );                                   // 自动对焦
                        }  catch (Exception e) {
                                e.printStackTrace();
                        }
                        isPreview =  true ;
                }
    }

}

class StreamIt  implements Camera.PreviewCallback {
        private String ipname;
        public StreamIt(String ipname){
                this .ipname = ipname;
        }

    @Override
    public void onPreviewFrame( byte [] data, Camera camera) {
        Size size = camera.getParameters().getPreviewSize();
        try {
                //调用image.compressToJpeg（）将YUV格式图像数据data转为jpg格式
            YuvImage image =  new YuvImage(data, ImageFormat.NV21, size.width, size.height,  null );
            if (image!= null ){
                    ByteArrayOutputStream outstream =  new ByteArrayOutputStream();
                image.compressToJpeg( new Rect( 0 ,  0 , size.width, size.height),  80 , outstream);
                outstream.flush();
                //启用线程将图像数据发送出去
                Thread th =  new MyThread(outstream,ipname);
                th.start();
            }
        } catch (Exception ex){
            Log.e( "Sys" , "Error:" +ex.getMessage());
        }
    }