安卓照相机 博客分类： Android多媒体技术 安卓照相机camera

关键技术：

SurfaceHolder.Callback

public class MyCameraDemo extends Activity {
	private SurfaceView surface = null ;
	private Button but = null ;
	private SurfaceHolder holder = null ;
	private Camera cam = null ;
	private boolean previewRunning =  true ;
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		super.setContentView(R.layout.main);
		this.but = (Button) super.findViewById(R.id.but) ;
		this.surface = (SurfaceView) super.findViewById(R.id.surface) ;
		
		this.holder = this.surface.getHolder() ;
		this.holder.addCallback(new MySurfaceViewCallback()) ;
		//设置缓冲类型
		this.holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS) ;
		//设置分辨率
		this.holder.setFixedSize(600, 350);
		
		this.but.setOnClickListener(new OnClickListenerImpl()) ;
	}
	private class OnClickListenerImpl implements OnClickListener {

		@Override
		public void onClick(View v) {
			if(MyCameraDemo.this.cam != null) {
				//自动对焦
				MyCameraDemo.this.cam.autoFocus(new AutoFocusCallbackImpl()) ;
			}
		}
		
	}
	
	private class MySurfaceViewCallback implements SurfaceHolder.Callback {

		//当预览界面格式大小改变时，调用
		public void surfaceChanged(SurfaceHolder holder, int format, int width,
				int height) {
			
		}

		//初次实例化界面调用
		public void surfaceCreated(SurfaceHolder holder) {
			MyCameraDemo.this.cam = Camera.open(0) ;	// 取得第一个摄像头
			//窗口服务
			WindowManager manager = (WindowManager) MyCameraDemo.this
					.getSystemService(Context.WINDOW_SERVICE);
			//取得display显示对象
			Display display = manager.getDefaultDisplay() ;
			//照相机参数
			Parameters param = MyCameraDemo.this.cam.getParameters() ;
			//将照相机预览大小设置为display大小
			param.setPreviewSize(display.getWidth(), display.getHeight()) ;
			param.setPreviewFrameRate(5) ;	// 一秒5帧
			param.setPictureFormat(PixelFormat.JPEG) ;	// 图片形式
			param.set("jpen-quality", 80) ;//图片质量，最高100
			MyCameraDemo.this.cam.setParameters(param) ;
			try {
				MyCameraDemo.this.cam.setPreviewDisplay(MyCameraDemo.this.holder) ;
			} catch (IOException e) {
			}
			MyCameraDemo.this.cam.startPreview() ;	// 进行预览
			MyCameraDemo.this.previewRunning = true ;	// 已经开始预览
		}

		@Override
		public void surfaceDestroyed(SurfaceHolder holder) {
			if(MyCameraDemo.this.cam != null) {
				if(MyCameraDemo.this.previewRunning) {
					MyCameraDemo.this.cam.stopPreview() ;	// 停止预览
					MyCameraDemo.this.previewRunning = false ;
				}
				MyCameraDemo.this.cam.release() ;
			}
		}
		
	}
	
	private class AutoFocusCallbackImpl implements AutoFocusCallback {

		@Override
		public void onAutoFocus(boolean success, Camera camera) {
			if(success) {	// 成功
				MyCameraDemo.this.cam.takePicture(sc, pc, jpgcall) ;
			}
		}
		
	}
	
	private PictureCallback jpgcall = new PictureCallback() {

		@Override
		public void onPictureTaken(byte[] data, Camera camera) {	// 保存图片的操作
			Bitmap bmp = BitmapFactory.decodeByteArray(data, 0, data.length);
			String fileName = Environment.getExternalStorageDirectory()
					.toString()
					+ File.separator
					+ "mldnphoto"
					+ File.separator
					+ "MLDN_" + System.currentTimeMillis() + ".jpg";
			File file = new File(fileName) ;
			if (!file.getParentFile().exists()) {
				file.getParentFile().mkdirs() ;	// 创建文件夹
			}
			try {
				BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream(file)) ;
				bmp.compress(Bitmap.CompressFormat.JPEG, 80, bos) ; // 向缓冲区之中压缩图片
				bos.flush() ;
				bos.close() ;
				Toast.makeText(MyCameraDemo.this,
						"拍照成功，照片已保存在" + fileName + "文件之中！", Toast.LENGTH_SHORT)
						.show();
			} catch (Exception e) {
				Toast.makeText(MyCameraDemo.this,
						"拍照失败！", Toast.LENGTH_SHORT)
						.show();
			}
			MyCameraDemo.this.cam.stopPreview() ;
			MyCameraDemo.this.cam.startPreview() ;
		}
		
	} ;
	
	private ShutterCallback sc = new ShutterCallback(){
		@Override
		public void onShutter() {
			// 按下快门之后进行的操作
		}
	} ;
	private PictureCallback pc = new PictureCallback() {

		@Override
		public void onPictureTaken(byte[] data, Camera camera) {
			
		}
		
	} ;
}

 

主布局函数

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 
	xmlns:android="http://schemas.android.com/apk/res/android"
	android:orientation="vertical" 
	android:layout_width="fill_parent"
	android:layout_height="fill_parent">
	<Button
		android:id="@+id/but" 
		android:layout_width="fill_parent"
		android:layout_height="wrap_content" 
		android:text="照相" />
	<SurfaceView
		android:id="@+id/surface"
		android:layout_width="fill_parent"
		android:layout_height="fill_parent" /> 
</LinearLayout>