How to use camera in Android
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An example Application of Android camera
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 ()); / / set buffer type this.holder.setType (SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); / / set resolution 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) {/ / autofocus MyCameraDemo.this.cam.autoFocus (new AutoFocusCallbackImpl ()) } private class MySurfaceViewCallback implements SurfaceHolder.Callback {/ / when the format of the preview interface changes, call public void surfaceChanged (SurfaceHolder holder, int format, int width, int height) {} / / the first instantiation interface calls public void surfaceCreated (SurfaceHolder holder) {MyCameraDemo.this.cam = Camera.open (0) / / get the first camera / / window service WindowManager manager = (WindowManager) MyCameraDemo.this .getSystemService (Context.WINDOW_SERVICE); / / get the display display object Display display = manager.getDefaultDisplay (); / / camera parameter Parameters param = MyCameraDemo.this.cam.getParameters () / / set the camera preview size to display size param.setPreviewSize (display.getWidth (), display.getHeight ()); param.setPreviewFrameRate (5); / / 5 frames per second param.setPictureFormat (PixelFormat.JPEG); / / Image format param.set ("jpen-quality", 80); / / Image quality, up to 100 MyCameraDemo.this.cam.setParameters (param) Try {MyCameraDemo.this.cam.setPreviewDisplay (MyCameraDemo.this.holder);} catch (IOException e) {} MyCameraDemo.this.cam.startPreview (); / / Preview MyCameraDemo.this.previewRunning = true / / Preview} @ Override public void surfaceDestroyed (SurfaceHolder holder) {if (MyCameraDemo.this.cam! = null) {if (MyCameraDemo.this.previewRunning) {MyCameraDemo.this.cam.stopPreview (); / / stop previewing MyCameraDemo.this.previewRunning = false;} MyCameraDemo.this.cam.release () } private class AutoFocusCallbackImpl implements AutoFocusCallback {@ Override public void onAutoFocus (boolean success, Camera camera) {if (success) {/ / successful MyCameraDemo.this.cam.takePicture (sc, pc, jpgcall) } private PictureCallback jpgcall = new PictureCallback () {@ Override public void onPictureTaken (byte [] data, Camera camera) {/ / the operation of saving the picture 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 () .jpg () / / create a folder} try {BufferedOutputStream bos = new BufferedOutputStream (new FileOutputStream (file)); bmp.compress (Bitmap.CompressFormat.JPEG, 80, bos); / / compress images into the buffer bos.flush (); bos.close () Toast.makeText (MyCameraDemo.this, "photo taken successfully, the photo has been saved in the" + fileName + "file! , Toast.LENGTH_SHORT) .show ();} catch (Exception e) {Toast.makeText (MyCameraDemo.this, "photo failed!" , Toast.LENGTH_SHORT) .show ();} MyCameraDemo.this.cam.stopPreview (); MyCameraDemo.this.cam.startPreview ();}}; private ShutterCallback sc = new ShutterCallback () {@ Override public void onShutter () {/ / actions taken after the shutter is pressed}} Private PictureCallback pc = new PictureCallback () {@ Override public void onPictureTaken (byte [] data, Camera camera) {}};}
Main layout function
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