android 手机照相流程

android 手机照相流程 android 手机拍照流程 android 拍照API流程 1. 在布局文件中添加一个 surfaceView (摄影平面) 2.根据 SurfaceView 获得 Holder (固定器) 3.给固定器设置 SurfaceHolder.Callback ; 这个 Callback 有一系列的周期方法, 比如:surfaceCreated,surfaceChanged,surfaceDestroyed等方法. ?.在surfaceDestroyed 中 打开相机,设置预览效果 ; ?.在surfaceChanged中可以初始化相机( Camera );比如相机的参数: 像素, 大小,格式,开始预览,等等 ?.在surfaceDestroyed可以可以停止相机拍摄;释放相机资源 4. 相机自动对焦 的回调处理 Camera.autoFocus( AutoFocusCallback ) AutoFocusCallback 有个接口方法 public void onAutoFocus(boolean focused, Camera camera) { /* 对到焦点拍照 */ if (focused) { takePicture();//见第5步 } } 5.Camera.takePicture(ShutterCallback shutter/*摄像*/, PictureCallback raw/*拍照 */, PictureCallback jpeg/*照片*/) 查看API或者源码,可以发现,这些callback里面都有包含摄像,或者被拍照时的byte[]数 据,而这些数据可以根据BitmapFactory变成Bitmap图片. 见源代码如下: public class ScanBarZBarActivity extends Activity implements SurfaceHolder.Callback{ private static String TAG = ScanBarZBarActivity ; private Camera mCamera; private Button mButton, mButton1, mButton2; private SurfaceView mSurfaceView; private SurfaceHolder holder; private AutoFocusCallback mAutoFocusCallback = new AutoFocusCallback(); private String path = WXJSMyPhoto ; private String path1; private Bitmap bmp; private int cnt = 1; private Calendar c; public native String getISBN(Bitmap bmp); private int flag=5; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); /* 隐藏状态栏 */ this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN); /* 隐藏标题栏 */ requestWindowFeature(Window.FEATURE_NO_TITLE); /* 设定屏幕显示为横向 */ this.setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE); setContentView(R.layout.camera); /* SurfaceHolder设定 */ mSurfaceView = (SurfaceView) findViewById(R.id.mSurfaceView); holder = mSurfaceView.getHolder(); holder.addCallback(ScanBarZBarActivity.this); holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); c = Calendar.getInstance(); /* Button初始化 */ mButton = (Button) findViewById(R.id.myButton); mButton1 = (Button) findViewById(R.id.myButton1); mButton2 = (Button) findViewById(R.id.myButton2); /* 拍照Button的事件处理 */ mButton.setOnClickListener(new Button.OnClickListener() { @Override public void onClick(View arg0) { /* 告动对焦后拍照 */ mCamera.autoFocus(mAutoFocusCallback); } }); /* Button的事件处理 */ mButton1.setOnClickListener(new Button.OnClickListener() { @Override public void onClick(View arg0) { /* 保存文件 */ Log.i(TAG, click button2 ); if (bmp != null) { /* 检查SDCard是否存在 */ if (!Environment.MEDIA_MOUNTED.equals(Environment .getExternalStorageState())) { /* SD卡不存在，显示Toast信息 */ Toast.makeText(ScanBarZBarActivity.this, SD卡不存在!无法保 存相片,请插入SD卡。 , Toast.LENGTH_LONG) .show(); } else { try { /* 文件不存在就创建 */ File f = new File(Environment .getExternalStorageDirectory(), path); Log.i(TAG, click button2: + f.getAbsolutePath()); if (!f.exists()) { f.mkdir(); } /* 保存相片文件 */ path1 = String.valueOf(c.get(Calendar.MILLISECOND)) + camera.jpg ; File n = new File(f, path1); FileOutputStream bos = new FileOutputStream(n .getAbsolutePath()); /* 文件转换 */ bmp.compress(Bitmap.CompressFormat.JPEG, 100, bos); /* 调用flush()方法，更新 BufferStream */ bos.flush(); /* 结束OutputStream */ bos.close(); Toast.makeText(ScanBarZBarActivity.this, path1 + 保 存成功! , Toast.LENGTH_LONG).show(); cnt++; } catch (Exception e) { e.printStackTrace(); } } } mButton.setVisibility(View.VISIBLE); mButton1.setVisibility(View.VISIBLE); mButton2.setVisibility(View.VISIBLE); /* 重新设定Camera */ stopCamera(); initCamera(); } }); /* 放弃Button的事件处理 */ mButton2.setOnClickListener(new Button.OnClickListener() { @Override public void onClick(View arg0) { mButton.setVisibility(View.VISIBLE); mButton1.setVisibility(View.VISIBLE); mButton2.setVisibility(View.VISIBLE); /* 重新设定Camera */ stopCamera(); initCamera(); } }); } @Override public void surfaceCreated(SurfaceHolder surfaceholder) { try { /* 打开相机， */ mCamera = Camera.open(); mCamera.setPreviewDisplay(holder); } catch (IOException exception) { mCamera.release(); mCamera = null; } } @Override public void surfaceChanged(SurfaceHolder surfaceholder, int format, int w, int h) { /* 相机初始化 */ Log.i(TAG, init camera ); initCamera(); } @Override public void surfaceDestroyed(SurfaceHolder surfaceholder) { Log.i(TAG, destoryed camera ); stopCamera(); mCamera.release(); mCamera = null; } /* 拍照的method */ private void takePicture() { if (mCamera != null) { Log.i(TAG, takePicture ); mCamera.takePicture(shutterCallback, rawCallback, jpegCallback); } } private ShutterCallback shutterCallback = new ShutterCallback() { public void onShutter() { } }; private PictureCallback rawCallback = new PictureCallback() { public void onPictureTaken(byte[] _data, Camera _camera) { } }; private PictureCallback jpegCallback = new PictureCallback() { public void onPictureTaken(byte[] _data, Camera _camera) { /* 取得相仞 */ try { /* 设定Button?视性 */ mButton.setVisibility(View.GONE); mButton1.setVisibility(View.VISIBLE); mButton2.setVisibility(View.VISIBLE); /* 取得相仞Bitmap对象 */ bmp = BitmapFactory.decodeByteArray(_data, 0, _data.length); //发送给isbn分析 // String isbn = getISBN(bmp);获得图片解析后的信息 // Log.i(TAG, isbn: + flag + isbn); flag--; if(flag 0){ mCamera.autoFocus(mAutoFocusCallback); } } catch (Exception e) { e.printStackTrace(); } } }; /* 告定义class AutoFocusCallback */ public final class AutoFocusCallback implements android.hardware.Camera.AutoFocusCallback { public void onAutoFocus(boolean focused, Camera camera) { /* 对到焦点拍照 */ if (focused) { takePicture(); } } }; /* 相机初始化的method */ private void initCamera() { if (mCamera != null) { try { Camera.Parameters parameters = mCamera.getParameters(); /* * 设定相片大小为1024*768， 格式为JPG */ parameters.setPictureFormat(PixelFormat.JPEG); parameters.setPictureSize(1024, 768); mCamera.setParameters(parameters); /* 开启预览画面 */ mCamera.startPreview(); } catch (Exception e) { e.printStackTrace(); } } } /* 停止相机的method */ private void stopCamera() { if (mCamera != null) { try { /* 停止预览 */ mCamera.stopPreview(); } catch (Exception e) { e.printStackTrace(); } } } } 1 楼 enefry 2011-05-24 不能修改对焦和曝光时间啊.