【流媒體】Android 实时视频采集—Camera预览采集

// 定义对象
 private SurfaceView mSurfaceview = null;  // SurfaceView对象：(视图组件)视频显示 
 private SurfaceHolder mSurfaceHolder = null;  // SurfaceHolder对象：(抽象接口)SurfaceView支持类 
 private Camera mCamera =null;     // Camera对象，相机预览

 // InitSurfaceView
 private void initSurfaceView()
 {
  mSurfaceview = (SurfaceView) this.findViewById(R.id.Surfaceview);
  mSurfaceHolder = mSurfaceview.getHolder(); // 绑定SurfaceView，取得SurfaceHolder对象
  mSurfaceHolder.addCallback(mainActivity.this); // SurfaceHolder加入回调接口
  // mSurfaceHolder.setFixedSize(176, 144); // 预览大小設置
  mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);// 設置顯示器類型，setType必须设置
 }

/*【SurfaceHolder.Callback 回调函数】*/
 public void surfaceCreated(SurfaceHolder holder)
 // SurfaceView启动时/初次实例化，预览界面被创建时，该方法被调用。
 {
  // TODO Auto-generated method stub  
  mCamera = Camera.open();// 开启摄像头（2.3版本后支持多摄像头,需传入参数） 
  try
  {   
   Log.i(TAG, "SurfaceHolder.Callback：surface Created");
   mCamera.setPreviewDisplay(mSurfaceHolder);//set the surface to be used for live preview

  } catch (Exception ex)
  {
   if(null != mCamera)
   {
    mCamera.release();
    mCamera = null;     
   }
   Log.i(TAG+"initCamera", ex.getMessage());
  }
 }
 public void surfaceChanged(SurfaceHolder holder, int format, int width, int height)
 // 当SurfaceView/预览界面的格式和大小发生改变时，该方法被调用
 {
  // TODO Auto-generated method stub  
  Log.i(TAG, "SurfaceHolder.Callback：Surface Changed");
  //mPreviewHeight = height;
  //mPreviewWidth = width;
  initCamera();  
 }
 public void surfaceDestroyed(SurfaceHolder holder) 
 // SurfaceView销毁时，该方法被调用
 {
  // TODO Auto-generated method stub
  Log.i(TAG, "SurfaceHolder.Callback：Surface Destroyed");
  if(null != mCamera)
  {
   mCamera.setPreviewCallback(null); //！！这个必须在前，不然退出出错
   mCamera.stopPreview(); 
   bIfPreview = false; 
   mCamera.release();
   mCamera = null;     
  }
 }

 1 /*【2】【相机预览】*/
 2  private void initCamera()//surfaceChanged中调用
 3  {
 4   Log.i(TAG, "going into initCamera");
 5   if (bIfPreview)
 6   {
 7    mCamera.stopPreview();//stopCamera();
 8   }
 9   if(null != mCamera)
10   {
11    try
12    {
13     /* Camera Service settings*/    
14     Camera.Parameters parameters = mCamera.getParameters();
15     // parameters.setFlashMode("off"); // 无闪光灯
16     parameters.setPictureFormat(PixelFormat.JPEG); //Sets the image format for picture 设定相片格式为JPEG，默认为NV21    
17     parameters.setPreviewFormat(PixelFormat.YCbCr_420_SP); //Sets the image format for preview picture，默认为NV21
18     /*【ImageFormat】JPEG/NV16(YCrCb format，used for Video)/NV21(YCrCb format，used for Image)/RGB_565/YUY2/YU12*/
19     
20     // 【调试】获取caera支持的PictrueSize，看看能否设置？？
21     List<Size> pictureSizes = mCamera.getParameters().getSupportedPictureSizes();
22     List<Size> previewSizes = mCamera.getParameters().getSupportedPreviewSizes();
23     List<Integer> previewFormats = mCamera.getParameters().getSupportedPreviewFormats();
24     List<Integer> previewFrameRates = mCamera.getParameters().getSupportedPreviewFrameRates();
25     Log.i(TAG+"initCamera", "cyy support parameters is ");
26     Size psize = null;
27     for (int i = 0; i < pictureSizes.size(); i++)
28     {
29      psize = pictureSizes.get(i);
30      Log.i(TAG+"initCamera", "PictrueSize,width: " + psize.width + " height" + psize.height);
31     }
32     for (int i = 0; i < previewSizes.size(); i++)
33     {
34      psize = previewSizes.get(i);
35      Log.i(TAG+"initCamera", "PreviewSize,width: " + psize.width + " height" + psize.height);
36     }
37     Integer pf = null;
38     for (int i = 0; i < previewFormats.size(); i++)
39     {
40      pf = previewFormats.get(i);
41      Log.i(TAG+"initCamera", "previewformates:" + pf);
42     }
43     
44     // 设置拍照和预览图片大小
45     parameters.setPictureSize(640, 480); //指定拍照图片的大小
46     parameters.setPreviewSize(mPreviewWidth, mPreviewHeight); // 指定preview的大小 
47 //这两个属性 如果这两个属性设置的和真实手机的不一样时，就会报错
48     
49 // 横竖屏镜头自动调整
50     if (this.getResources().getConfiguration().orientation != Configuration.ORIENTATION_LANDSCAPE) 
51     {
52      parameters.set("orientation", "portrait"); //
53      parameters.set("rotation", 90); // 镜头角度转90度（默认摄像头是横拍） 
54      mCamera.setDisplayOrientation(90); // 在2.2以上可以使用
55     } else// 如果是横屏
56     {
57      parameters.set("orientation", "landscape"); //
58      mCamera.setDisplayOrientation(0); // 在2.2以上可以使用
59     } 
60     
61     /* 视频流编码处理 */ 
62     //添加对视频流处理函数
63     
64     
65 // 设定配置参数并开启预览
66     mCamera.setParameters(parameters); // 将Camera.Parameters设定予Camera    
67     mCamera.startPreview(); // 打开预览画面
68     bIfPreview = true;
69     
70     // 【调试】设置后的图片大小和预览大小以及帧率
71     Camera.Size csize = mCamera.getParameters().getPreviewSize();
72     mPreviewHeight = csize.height; //
73     mPreviewWidth = csize.width;
74     Log.i(TAG+"initCamera", "after setting, previewSize:width: " + csize.width + " height: " + csize.height);
75     csize = mCamera.getParameters().getPictureSize();
76     Log.i(TAG+"initCamera", "after setting, pictruesize:width: " + csize.width + " height: " + csize.height);
77     Log.i(TAG+"initCamera", "after setting, previewformate is " + mCamera.getParameters().getPreviewFormat());
78     Log.i(TAG+"initCamera", "after setting, previewframetate is " + mCamera.getParameters().getPreviewFrameRate());
79    } catch (Exception e)
80    { 
81     e.printStackTrace();
82    }
83   }
84  }

 1  // 【获取视频预览帧的接口】
 2   mJpegPreviewCallback = new Camera.PreviewCallback()
 3   {
 4    @Override
 5    public void onPreviewFrame(byte[] data, Camera camera) 
 6    {
 7     //传递进来的data,默认是YUV420SP的
 8 // TODO Auto-generated method stub    
 9     try
10     {
11      Log.i(TAG, "going into onPreviewFrame");
12      //mYUV420sp = data;   // 获取原生的YUV420SP数据
13      YUVIMGLEN = data.length;
14      
15      // 拷贝原生yuv420sp数据
16      mYuvBufferlock.acquire();
17      System.arraycopy(data, 0, mYUV420SPSendBuffer, 0, data.length);
18      //System.arraycopy(data, 0, mWrtieBuffer, 0, data.length);
19      mYuvBufferlock.release();
20      
21      // 开启编码线程，如开启PEG编码方式线程
22      mSendThread1.start();
23      
24     } catch (Exception e)
25     {
26      Log.v("System.out", e.toString());
27     }// endtry    
28    }// endonPriview  
29   };