Develop Reference

Camera Preview on Android

I am trying to make a camera application on Android, no errors in Log-cat but the application doesn't close when i press the back button ; and if i want to open another application camera after stopping it; the camera is locked !! any hint or ideas ?
Thanks in advance.
public class Capture extends Activity {
private Camera mCamera;
private ViewCamera mPreview;
public static final int MEDIA_TYPE_IMAGE = 1;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.camera);
releaseCamera();
// Create an instance of Camera
mCamera = getCameraInstance();
Log.d("EyeSeeJD", "getCameraInstance");
// Create our Preview view and set it as the content of our activity.
mPreview = new ViewCamera(this, mCamera);
FrameLayout preview = (FrameLayout) findViewById(R.id.frame);
Log.d("EyeSeeJD", "addview ");
preview.addView(mPreview);
}
/** A safe way to get an instance of the Camera object. */
public static Camera getCameraInstance() {
Camera c = null;
try {
c = Camera.open(); // attempt to get a Camera instance
// c.lock();
} catch (Exception e) {
// Camera is not available (in use or does not exist)
Log.d("EyeSeeJD", "can't open camera ");
}
return c; // returns null if camera is unavailable
}
/** Create a File for saving an image or video */
private static File getOutputMediaFile(int type) {
// To be safe, you should check that the SDCard is mounted
// using Environment.getExternalStorageState() before doing this.
File mediaStorageDir = new File(
Environment
.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES),
"MyCameraApp");
// This location works best if you want the created images to be shared
// between applications and persist after your app has been uninstalled.
// Create the storage directory if it does not exist
if (!mediaStorageDir.exists()) {
if (!mediaStorageDir.mkdirs()) {
Log.d("MyCameraApp", "failed to create directory");
return null;
}
}
// Create a media file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss")
.format(new Date());
File mediaFile;
if (type == MEDIA_TYPE_IMAGE) {
mediaFile = new File(mediaStorageDir.getPath() + File.separator
+ "IMG_" + timeStamp + ".jpg");
} else {
return null;
}
return mediaFile;
}
private PictureCallback mPicture = new PictureCallback() {
#Override
public void onPictureTaken(byte[] data, Camera camera) {
File pictureFile = getOutputMediaFile(MEDIA_TYPE_IMAGE);
if (pictureFile == null) {
Log.d("EyeSeeJD",
"Error creating media file, check storage permissions ");
return;
}
try {
FileOutputStream fos = new FileOutputStream(pictureFile);
fos.write(data);
fos.close();
} catch (FileNotFoundException e) {
Log.d("EyeSeeJD", "File not found: " + e.getMessage());
} catch (IOException e) {
Log.d("EyeSeeJD", "Error accessing file: " + e.getMessage());
}
}
};
#Override
protected void onResume() {
super.onResume();
/*
* if (mCamera == null) { releaseCamera(); // release the camera
* immediately on pause event System.exit(0); }
*/
}
#Override
protected void onPause() {
super.onPause();
releaseCamera(); // release the camera immediately on pause event
// System.exit(0);
}
private void releaseCamera() {
if (mCamera != null) {
mCamera.stopPreview();
mCamera.setPreviewCallback(null);
mPreview.getHolder().removeCallback(mPreview);
// mCamera.unlock();
mCamera.release(); // release the camera for other applications
mCamera = null;
}
}
#Override
public void onBackPressed() { // TODO Auto-generated methodstub
super.onBackPressed();
//mCamera.setPreviewCallback(null);
//mPreview.getHolder().removeCallback(mPreview);
mCamera.stopPreview();
mCamera.release(); // release the camera for other applications
mCamera = null;
finish();
System.exit(0);
}
#Override
public boolean onTouchEvent(MotionEvent event) {
// TODO Auto-generated method stub
//mCamera.setPreviewCallback(null);
mCamera.takePicture(null, null, mPicture);
//mCamera.release();
// mCamera.startPreview();
return super.onTouchEvent(event);
}
#Override
protected void onDestroy() {
// TODO Auto-generated method stub
super.onDestroy();
mCamera.stopPreview();
mCamera.setPreviewCallback(null);
mPreview.getHolder().removeCallback(mPreview);
mCamera.release(); // release the camera for other applications
mCamera = null;
finish();
System.exit(0);
}
}
ViewCamera.java
public class ViewCamera extends SurfaceView implements SurfaceHolder.Callback {
private SurfaceHolder mHolder = null;
private Camera mCamera = null;
public ViewCamera(Context context, Camera camera) {
super(context);
mCamera = camera;
// Install a SurfaceHolder.Callback so we get notified when the
// underlying surface is created and destroyed.
mHolder = getHolder();
mHolder.addCallback(this);
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
// TODO Auto-generated method stub
// The Surface has been created, now tell the camera where to draw the
// preview.
try {
mCamera.setPreviewDisplay(holder);
mCamera.startPreview();
} catch (IOException e) {
Log.d("EyeSeeJD", "Error setting camera preview: " + e.getMessage());
}
}
// check if device has camera
private boolean checkCameraHardware(Context context) {
if (context.getPackageManager().hasSystemFeature(
PackageManager.FEATURE_CAMERA)) {
// this device has a camera
Log.d("EyeSeeJd", "there is a camera ");
return true;
} else {
// no camera on this device
Log.d("EyeSeeJd", "there is no camera ");
return false;
}
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
// TODO Auto-generated method stub
// If your preview can change or rotate, take care of those events here.
// Make sure to stop the preview before resizing or reformatting it.
if (mHolder.getSurface() == null) {
// preview surface does not exist
return;
}
// stop preview before making changes
try {
mCamera.stopPreview();
} catch (Exception e) {
// ignore: tried to stop a non-existent preview
}
// set preview size and make any resize, rotate or
// reformatting changes here
/*Camera.Parameters parameters = mCamera.getParameters();
parameters.setPreviewSize(320, 480);
mCamera.setParameters(parameters);*/
// start preview with new settings
try {
mCamera.setPreviewDisplay(mHolder);
mCamera.startPreview();
// mCamera.unlock();
} catch (Exception e) {
Log.d("EyeSeeJd",
"Error starting camera preview: " + e.getMessage());
}
}
#Override
public void surfaceDestroyed(SurfaceHolder arg0) {
// TODO Auto-generated method stub
// empty. Take care of releasing the Camera preview in your activity.
this.getHolder().removeCallback(this);
mCamera.stopPreview();
mCamera.release();
mCamera = null;
}
}

It's hard to tell what really happens without following your code in debugger, but there is a chance that you call Camera.release() too many times. There may be NullPointerExeception somewhere that prevents normal shutdown. There should be only one release in your app, and onPause() is a perfect place to call releaseCamera(). I don't see why you need to override onBackPressed() at all, calling finish() from this override is not recommended, and calling System.exit() even more so. Also, I would move call to getCameraInstance() to onResume() or maybe to onStart().

The reason why your app takes time to close when you press back is that your app is crashing because in onBackPressed() method you are setting mCamera to null and in onDestroy() you are using it again to stop and releasing camera.

Getting a Camera error 100 and a Method called after release error

I'm playing with the google tutorial on using video recorders but I can't get it to work anyhow. I first keep getting at Method called after release error, for the camera preview which I tracked down to realize that mCamera.stoppreview() doesn't work before the startpreview is called again onSurfaceChanged(). Also I get a Camera 100 error with mediaserver died, camera server died and icamera died when MediaRecorder.start() is called. I can't seem to figure out why.
Here is my CameraActivity code
public class MainActivity extends Activity {
private Camera mCamera;
private MediaRecorder mMediaRecorder;
private CameraPreview mPreview;
private static final String TAG = "Message";
public static final int MEDIA_TYPE_IMAGE = 1;
public static final int MEDIA_TYPE_VIDEO = 2;
private boolean isRecording = false;
Button captureButton;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.preview);
System.out.println("Going to get the camera");
mCamera = getCameraInstance();
//mMediaRecorder = new MediaRecorder();
mPreview = new CameraPreview(this, mCamera);
FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview);
preview.addView(mPreview);
// setPreviewCallback(null);
captureButton = (Button) findViewById(R.id.button_capture);
captureButton.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
if (isRecording) {
// stop recording and release camera
mMediaRecorder.stop(); // stop the recording
releaseMediaRecorder(); // release the MediaRecorder object
mCamera.lock(); // take camera access back from MediaRecorder
// inform the user that recording has stopped
captureButton.setText("Capture");
isRecording = false;
} else {
// initialize video camera
releaseCamera();
if (prepareVideoRecorder()) {
System.out.println("Starting to record");
// Camera is available and unlocked, MediaRecorder is prepared,
// now you can start recording
mMediaRecorder.start();
// inform the user that recording has started
captureButton.setText("Stop");
isRecording = true;
} else {
// prepare didn't work, release the camera
System.out.println("Recording failed");
releaseMediaRecorder();
// inform user
}
}
}
}
);
}
public static Camera getCameraInstance(){
Camera c = null;
try {
c = Camera.open();
System.out.println("This is the camera "+c);// attempt to get a Camera instance
}
catch (Exception e){
// Camera is not available (in use or does not exist)
System.out.println("Didn't get the camera ");
}
return c; // returns null if camera is unavailable
}
private boolean prepareVideoRecorder(){
mCamera = getCameraInstance();
mMediaRecorder = new MediaRecorder();
/*CameraPreview preview;
preview=new CameraPreview(this, mCamera);*/
// Step 1: Unlock and set camera to MediaRecorder
mCamera.unlock();
mMediaRecorder.setCamera(mCamera);
// Step 2: Set sources
mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.CAMCORDER);
mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
// Step 3: Set a CamcorderProfile (requires API Level 8 or higher)
mMediaRecorder.setProfile(CamcorderProfile.get(CamcorderProfile.QUALITY_HIGH));
// Step 4: Set output file
mMediaRecorder.setOutputFile(getOutputMediaFile(MEDIA_TYPE_VIDEO).toString());
// Step 5: Set the preview output
System.out.println("About to preview");
mMediaRecorder.setPreviewDisplay(mPreview.getHolder().getSurface());
System.out.println("Preview worked");
// Step 6: Prepare configured MediaRecorder
try {
mMediaRecorder.prepare();
} catch (IllegalStateException e) {
Log.d(TAG, "IllegalStateException preparing MediaRecorder: " + e.getMessage());
releaseMediaRecorder();
return false;
} catch (IOException e) {
Log.d(TAG, "IOException preparing MediaRecorder: " + e.getMessage());
releaseMediaRecorder();
return false;
}
return true;
}
#Override
protected void onPause() {
super.onPause();
releaseMediaRecorder(); // if you are using MediaRecorder, release it first
releaseCamera(); // release the camera immediately on pause event
}
private void releaseMediaRecorder(){
if (mMediaRecorder != null) {
mMediaRecorder.reset(); // clear recorder configuration
mMediaRecorder.release(); // release the recorder object
mMediaRecorder = null;
mCamera.lock(); // lock camera for later use
}
}
private void releaseCamera(){
if (mCamera != null){
mCamera.stopPreview();
mCamera.setPreviewCallback(null);
mCamera.release(); // release the camera for other applications
mCamera = null;
}
}
private PictureCallback mPicture = new PictureCallback() {
#Override
public void onPictureTaken(byte[] data, Camera camera) {
System.out.println("Picture received");
File pictureFile = getOutputMediaFile(MEDIA_TYPE_IMAGE);
if (pictureFile == null){
Log.d(TAG, "Error creating media file, check storage permissions: ");
return;
}
try {
System.out.println("Saving");
FileOutputStream fos = new FileOutputStream(pictureFile);
fos.write(data);
fos.close();
} catch (FileNotFoundException e) {
Log.d(TAG, "File not found: " + e.getMessage());
} catch (IOException e) {
Log.d(TAG, "Error accessing file: " + e.getMessage());
}
}
};
/** Create a File for saving an image or video */
/** Create a File for saving an image or video */
private static File getOutputMediaFile(int type){
// To be safe, you should check that the SDCard is mounted
// using Environment.getExternalStorageState() before doing this.
System.out.println("Trying to save picture");
File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_PICTURES), "MyCameraApp");
// This location works best if you want the created images to be shared
// between applications and persist after your app has been uninstalled.
// Create the storage directory if it does not exist
if (! mediaStorageDir.exists()){
if (! mediaStorageDir.mkdirs()){
Log.d("MyCameraApp", "failed to create directory");
return null;
}
}
// Create a media file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
File mediaFile;
if (type == MEDIA_TYPE_IMAGE){
mediaFile = new File(mediaStorageDir.getPath() + File.separator +
"IMG_"+ timeStamp + ".jpg");
} else if(type == MEDIA_TYPE_VIDEO) {
mediaFile = new File(mediaStorageDir.getPath() + File.separator +
"VID_"+ timeStamp + ".mp4");
} else {
return null;
}
return mediaFile;
}
}
and this is my CameraPreview class
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
private static final String TAG = "Message";
private SurfaceHolder mHolder;
private Camera mCamera;
public CameraPreview(Context context, Camera camera) {
super(context);
mCamera = camera;
// Install a SurfaceHolder.Callback so we get notified when the
// underlying surface is created and destroyed.
mHolder = getHolder();
mHolder.addCallback(this);
// deprecated setting, but required on Android versions prior to 3.0
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
public void surfaceCreated(SurfaceHolder holder) {
// The Surface has been created, now tell the camera where to draw the preview.
try {
mCamera.setPreviewDisplay(holder);
mCamera.startPreview();
} catch (IOException e) {
Log.d(TAG, "Error setting camera preview: " + e.getMessage());
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
// empty. Take care of releasing the Camera preview in your activity.
/*mCamera.setPreviewCallback(null);
mCamera.stopPreview();
mCamera.release();*/
}
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
// If your preview can change or rotate, take care of those events here.
// Make sure to stop the preview before resizing or reformatting it.
if (mHolder.getSurface() == null){
// preview surface does not exist
return;
}
// stop preview before making changes
try {
mCamera.stopPreview();
} catch (Exception e){
// ignore: tried to stop a non-existent preview
System.out.println("Stop preview didn't work ");
}
// set preview size and make any resize, rotate or
// reformatting changes here
// start preview with new settings
try {
mCamera.setPreviewDisplay(mHolder);
mCamera.startPreview();
} catch (Exception e){
Log.d(TAG, "Error starting camera preview: " + e.getMessage());
}
}
}
EDIT:
XML Layout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<FrameLayout
android:id="#+id/camera_preview"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1"
/>
<Button
android:id="#+id/button_capture"
android:text="Capture"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
/>
</LinearLayout>

I was also able to fix this issue by removing the call to mCamera.release() in onPause(). Here's some code:
//kv Only call release here if we're running an OS later than Gingerbread, otherwise, camera will freeze
if (android.os.Build.VERSION.SDK_INT > Build.VERSION_CODES.GINGERBREAD_MR1)
{
mCamera.release();
}

Camera Preview not visible after App Resumes

I am developing this app which requires access to the camera. I have accessed it well. But there are two issues.
The preview is all stretched when the phone is vertical. Secondly, the camera preview isn't visible when I resume the app. The camera.open() function does opens the camera but I am not able to see the preview. I have tried all the help available on the forum but nothing is actually solving my problem.
-Thanks in advance!
//Camera Activity file
#SuppressLint("SimpleDateFormat")
public class CameraActivity extends Activity {
private Camera mCamera;
private CameraPreview mPreview;
private FrameLayout preview;
private Button bCapture;
private Button bGallery;
private static final String TAG = "CameraActivity";
private static final int PICK_IMAGE_REQUEST = 1;
private TextView tvCheck;
public final static String EXTRA_MESSAGE = "com.epfl.mycamera.MESSAGE";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().requestFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_camera);
if (checkCameraHardware(getBaseContext())){
// Create an instance of Camera
mCamera = getCameraInstance();
// Create our Preview view and set it as the content of our activity.
mPreview = new CameraPreview(this, mCamera, CameraActivity.this);
preview = (FrameLayout) findViewById(R.id.camera_preview);
preview.addView(mPreview);
//Adding Camera Button
bCapture = (Button) findViewById(R.id.bCapture);
//Button Listener for storing images
bCapture.setOnClickListener( new View.OnClickListener() {
#Override
public void onClick(View v) {
mCamera.takePicture(null, null, null, jpegCallback);
mCamera.startPreview();
Log.d(TAG, "takePicture");
}
});
//Adding Gallery Button
bGallery = (Button) findViewById (R.id.bGallery);
bGallery.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
tvCheck = (TextView) findViewById (R.id.tvCheck);
selectImageFromGallery();
}
});
}
Log.d(TAG, "OnCreate");
}
/******************************************************************/
public void selectImageFromGallery() {
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, "Select Picture"),PICK_IMAGE_REQUEST);
}
#Override
protected void onActivityResult(int aRequestCode, int aResultCode, Intent aData) {
switch (aRequestCode) {
case PICK_IMAGE_REQUEST:
handleImage(aData);
break;
default:
tvCheck.setText("You can only select images.");
break;
}
super.onActivityResult(aRequestCode, aResultCode, aData);
}
private void handleImage(Intent aData) {
if ((aData != null) && (aData.getData() != null)) {
Uri selectedImage = aData.getData();
String[] filePathColumn = {MediaColumns.DATA};
Cursor cursor = getContentResolver().query(selectedImage, filePathColumn, null, null, null);
cursor.moveToFirst();
Log.d("ImageActivity", "After extracting file Path");
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
String picturePath = cursor.getString(columnIndex);
cursor.close();
Log.d("ImageActivity", "After closing the cursor");
setContentView(R.layout.activity_image_old); //setting the view to the image
ImageView imgView = (ImageView) findViewById(R.id.ivGallery);
imgView.setImageBitmap(BitmapFactory.decodeFile(picturePath));
Button bLiveCamera = (Button) findViewById(R.id.bCameraPreview);
bLiveCamera.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
setContentView(R.layout.activity_camera);
mCamera.startPreview();
}
});
}
else {
tvCheck.setText("You did not select an image");
}
}
/****************************************************************/
/** Stores jpeg picture */
PictureCallback jpegCallback = new PictureCallback() {
public void onPictureTaken(byte[] data, Camera camera) {
try {
File mediaStorageDir = new File(Environment .getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES),"MyCamera");
// Saving image to the SD CARD with a file operation
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
File mediaFile;
mediaFile = new File(mediaStorageDir.getPath() + File.separator +"IMG_"+ timeStamp + ".jpg");
FileOutputStream outStream = new FileOutputStream(mediaFile);
outStream.write(data);
outStream.close();
sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, Uri.parse("file://"+ Environment.getExternalStorageDirectory())));
Log.d(TAG, "onPictureTaken - wrote bytes: " + data.length);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
} Log.d(TAG, "onPictureTaken - jpeg");
}
};
/***************************************************************/
/** Check if this device has a camera */
private boolean checkCameraHardware(Context context) {
if (context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA)){
Log.d(TAG, "Camera Available");
return true;
} else {
Log.d(TAG, "No Camera Found");
return false;
}
}
/** A safe way to get an instance of the Camera object. */
public Camera getCameraInstance(){
Camera c = null;
try {
int i = Camera.getNumberOfCameras();
releaseCamera(); //in case camera is being accessed by any other app.
Log.d(TAG, "Number of Cameras "+i +"\n");
c = Camera.open(); // attempt to get a Camera instance
Log.d(TAG, "Camera Opened");
}
catch (Exception e){
Log.d(TAG, "Camera Can't Be Accessed");
}
return c; // returns null if camera is unavailable
}
#Override
protected void onPause() {
super.onPause();
releaseCamera(); // release the camera immediately on pause event
}
private void releaseCamera(){
if (mCamera != null){
mPreview.getHolder().removeCallback(mPreview);
mCamera.release(); // release the camera for other applications
}
}
#Override
public void onResume() {
super.onResume();
// Get the Camera instance as the activity achieves full user focus
if (mCamera == null) {
getCameraInstance();
mCamera.startPreview();
}
}
}
this is my camera preview class:
#SuppressLint({ "ViewConstructor", "SdCardPath" })
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
private static final String TAG = "CameraPreview";
private SurfaceHolder mHolder;
private Camera mCamera;
private Size mPreviewSize;
// private Activity CameraActivity;
#SuppressWarnings("deprecation")
public CameraPreview(Context context, Camera camera, Activity activity) {
super(context);
mCamera = camera;
//CameraActivity = activity;
// Install a SurfaceHolder.Callback so we get notified when the
// underlying surface is created and destroyed.
mHolder = getHolder();
mHolder.addCallback(this);
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
public void surfaceCreated(SurfaceHolder holder) {
// The Surface has been created, now tell the camera where to draw the preview.
try {
mCamera.setPreviewDisplay(holder);
//add camera preview call back here.
mCamera.startPreview();
} catch (IOException e) {
Log.d(TAG, "Error setting camera preview: " + e.getMessage());
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
// empty. Take care of releasing the Camera preview in your activity.
}
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
// If your preview can change or rotate, take care of those events here.
// Make sure to stop the preview before resizing or reformatting it.
if (mHolder.getSurface() == null){
// preview surface does not exist
return;
}
// stop preview before making changes
try{
mCamera.stopPreview();
} catch (Exception e){
// ignore: tried to stop a non-existent preview
}
// set preview size and make any resize, rotate or
// reformatting changes here
Camera.Parameters parameters = mCamera.getParameters();
List<Size> localSizes = mCamera.getParameters().getSupportedPreviewSizes();
mPreviewSize = localSizes.get(0);
Log.d(TAG, "Width " + mPreviewSize.width);
Log.d(TAG, "Height " + mPreviewSize.height);
parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height );
mHolder.setFixedSize(mPreviewSize.width, mPreviewSize.height);
requestLayout();
mCamera.setParameters(parameters);
//start preview with new settings
try {
mCamera.setPreviewDisplay(mHolder);
mCamera.setDisplayOrientation(90);
//setCameraDisplayOrientation(CameraActivity, 0, mCamera);
mCamera.startPreview();
} catch (Exception e){
Log.d(TAG, "Error starting camera preview: " + e.getMessage());
}
}
}

You create a CameraPreview only onCreate() of your Activity. But the camera instance is released onPause(), and a new one is opened onResume(). Therefore, you need to set the surface again.

Open default camera on SurfaceView and record with front camera

I have write this code to open the front camera on surfaceview in the screen, but when you click on the button i want to record a video with front camera.
This code crash. i have used two different variable for the cameras, but i don t find my error :(.. I have followed the google guide.
public class MainActivity extends Activity {
public static final int MEDIA_TYPE_VIDEO = 2;
private Camera mCamera;
private CameraPreview mPreview;
public static final int MEDIA_TYPE_IMAGE = 1;
protected static final String TAG = null;
private MediaRecorder mMediaRecorder;
private Camera mCamerafront;
private boolean isRecording = false;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Button captureButton = (Button) findViewById(id.button_capture);
mCamera = getCameraInstance();
// Create our Preview view and set it as the content of our activity.
mPreview = new CameraPreview(this, mCamera);
FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview);
preview.addView(mPreview);
// Add a listener to the Capture button
Button captureButton = (Button) findViewById(id.button_capture);
captureButton.setOnClickListener(
new View.OnClickListener() {
public void onClick(View v) {
if (isRecording) {
// stop recording and release camera
mMediaRecorder.stop(); // stop the recording
releaseMediaRecorder(); // release the MediaRecorder object
mCamerafront.lock(); // take camera access back from MediaRecorder
// inform the user that recording has stopped
//setCaptureButtonText("Capture");
isRecording = false;
} else {
// initialize video camera
if (prepareVideoRecorder()) {
// Camera is available and unlocked, MediaRecorder is prepared,
// now you can start recording
mMediaRecorder.start();
// inform the user that recording has started
//setCaptureButtonText("Stop");
isRecording = true;
} else {
// prepare didn't work, release the camera
releaseMediaRecorder();
// inform user
}
}
}
}
);
/* captureButton.setOnClickListener(
new View.OnClickListener() {
public void onClick(View v) {
// get an image from the camera
mCamera.takePicture(null, null, mPicture);
}
}
);*/
}
//*PARTE registrazione
private boolean prepareVideoRecorder(){
int cameraCount = Camera.getNumberOfCameras()-1;
mCamerafront=Camera.open(cameraCount);
mMediaRecorder = new MediaRecorder();
mCamerafront.unlock();
mMediaRecorder.setCamera(mCamerafront);
mMediaRecorder.setAudioSource(MediaRecorder.AudioSource.CAMCORDER);
mMediaRecorder.setVideoSource(MediaRecorder.VideoSource.CAMERA);
mMediaRecorder.setProfile(CamcorderProfile.get(CamcorderProfile.QUALITY_HIGH));
mMediaRecorder.setOutputFile(getOutputMediaFile(MEDIA_TYPE_VIDEO).toString());
try {
mMediaRecorder.prepare();
} catch (IllegalStateException e) {
Log.d(TAG, "IllegalStateException preparing MediaRecorder: " + e.getMessage());
// releaseMediaRecorder();
return false;
} catch (IOException e) {
Log.d(TAG, "IOException preparing MediaRecorder: " + e.getMessage());
//releaseMediaRecorder();
return false;
}
return true;
}
private void releaseMediaRecorder(){
if (mMediaRecorder != null) {
mMediaRecorder.reset(); // clear recorder configuration
mMediaRecorder.release(); // release the recorder object
mMediaRecorder = null;
mCamerafront.lock(); // lock camera for later use
}
}
/** Check if this device has a camera */
private boolean checkCameraHardware(Context context) {
if (context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA)){
// this device has a camera
return true;
} else {
// no camera on this device
return false;
}
}
/** A safe way to get an instance of the Camera object. */
public static Camera getCameraInstance(){
Camera c = null;
try {
c = Camera.open(); // attempt to get a Camera instance
}
catch (Exception e){
// Camera is not available (in use or does not exist)
}
return c; // returns null if camera is unavailable
}
/** A basic Camera preview class */
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
private final String TAG = null;
private SurfaceHolder mHolder;
private Camera mCamera;
public CameraPreview(Context context, Camera camera) {
super(context);
mCamera = camera;
// Install a SurfaceHolder.Callback so we get notified when the
// underlying surface is created and destroyed.
mHolder = getHolder();
mHolder.addCallback(this);
// deprecated setting, but required on Android versions prior to 3.0
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
public void surfaceCreated(SurfaceHolder holder) {
// The Surface has been created, now tell the camera where to draw the preview.
try {
mCamera.setPreviewDisplay(holder);
mCamera.startPreview();
} catch (IOException e) {
Log.d(TAG, "Error setting camera preview: " + e.getMessage());
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
// empty. Take care of releasing the Camera preview in your activity.
}
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
// If your preview can change or rotate, take care of those events here.
// Make sure to stop the preview before resizing or reformatting it.
if (mHolder.getSurface() == null){
// preview surface does not exist
return;
}
// stop preview before making changes
try {
mCamera.stopPreview();
} catch (Exception e){
// ignore: tried to stop a non-existent preview
}
// set preview size and make any resize, rotate or
// reformatting changes here
// start preview with new settings
try {
mCamera.setPreviewDisplay(mHolder);
mCamera.startPreview();
} catch (Exception e){
Log.d(TAG, "Error starting camera preview: " + e.getMessage());
}
}
}
#Override
protected void onPause() {
super.onPause();
// if you are using MediaRecorder, release it first
releaseCamera(); // release the camera immediately on pause event
}
private void releaseCamera(){
if (mCamera != null){
mCamera.release(); // release the camera for other applications
mCamera = null;
}
}
private PictureCallback mPicture = new PictureCallback() {
public void onPictureTaken(byte[] data, Camera camera) {
File pictureFile = getOutputMediaFile(MEDIA_TYPE_IMAGE);
try {
FileOutputStream fos = new FileOutputStream(pictureFile);
fos.write(data);
fos.close();
} catch (FileNotFoundException e) {
Log.d(TAG, "File not found: " + e.getMessage());
} catch (IOException e) {
Log.d(TAG, "Error accessing file: " + e.getMessage());
}
}
};
private static Uri getOutputMediaFileUri(int type){
return Uri.fromFile(getOutputMediaFile(type));
}
/** Create a File for saving an image or video */
private static File getOutputMediaFile(int type){
// To be safe, you should check that the SDCard is mounted
// using Environment.getExternalStorageState() before doing this.
File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_PICTURES), "MyCameraApp");
// This location works best if you want the created images to be shared
// between applications and persist after your app has been uninstalled.
// Create the storage directory if it does not exist
if (! mediaStorageDir.exists()){
if (! mediaStorageDir.mkdirs()){
Log.d("MyCameraApp", "failed to create directory");
return null;
}
}
// Create a media file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
File mediaFile;
if (type == MEDIA_TYPE_IMAGE){
mediaFile = new File(mediaStorageDir.getPath() + File.separator +
"IMG_"+ timeStamp + ".jpg");
} else if(type == MEDIA_TYPE_VIDEO) {
mediaFile = new File(mediaStorageDir.getPath() + File.separator +
"VID_"+ timeStamp + ".mp4");
} else {
return null;
}
return mediaFile;
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
}

You need to add the following permission in yout AndroidManifest.xml file:
<uses-permission android:name="android.permission.RECORD_AUDIO" />

camera preview is not restarting?

I am working on the camera code in android to take picture and save it on the phone. It takes the picture from phone camera and saves it on the memory card. The only problem is that the camera preview does not restart after taking the picture.
I cannot figure out the solution. Code is as follows. Suggestions are needed . . .
There are two classes in my project . . .
CAMERAACTIVITY CLASS
public class CameraActivity extends Activity
{
private static final String TAG = "CameraDemo";
Preview preview;
Button buttonClick;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
preview = new Preview(this);
((FrameLayout) findViewById(R.id.preview)).addView(preview);
buttonClick = (Button) findViewById(R.id.buttonClick);
buttonClick.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
preview.camera.takePicture(shutterCallback, rawCallback, jpegCallback);
}
});
Log.d(TAG, "onCreate'd");
}
// Called when shutter is opened
ShutterCallback shutterCallback = new ShutterCallback() {
public void onShutter() {
Log.d(TAG, "onShutter'd");
}
};
// Handles data for raw picture
PictureCallback rawCallback = new PictureCallback() {
public void onPictureTaken(byte[] data, Camera camera) {
Log.d(TAG, "onPictureTaken - raw");
}
};
// Handles data for jpeg picture
PictureCallback jpegCallback = new PictureCallback() {
public void onPictureTaken(byte[] data, Camera camera) {
FileOutputStream outStream = null;
try {
// Write to SD Card
outStream = new FileOutputStream(String.format("/sdcard/DCIM/queries.jpg",
System.currentTimeMillis()));
outStream.write(data);
outStream.close();
Log.d(TAG, "onPictureTaken - wrote bytes: " + data.length);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
}
Log.d(TAG, "onPictureTaken - jpeg");
}
};
}
Preview Class
class Preview extends SurfaceView implements SurfaceHolder.Callback{
private static final String TAG = "Preview";
SurfaceHolder mHolder; // <2>
public Camera camera; // <3>
Preview(Context context) {
super(context);
// Install a SurfaceHolder.Callback so we get notified when the
// underlying surface is created and destroyed.
mHolder = getHolder(); // <4>
mHolder.addCallback(this); // <5>
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); // <6>
}
// Called once the holder is ready
public void surfaceCreated(SurfaceHolder holder) { // <7>
// The Surface has been created, acquire the camera and tell it where
// to draw.
camera = Camera.open(); // <8>
try {
Camera.Parameters parameters = camera.getParameters();
parameters.set("orientation", "landscape");
camera.setParameters(parameters);
camera.setPreviewDisplay(holder);
camera.setPreviewCallback(new PreviewCallback() {
// Called for each frame previewed
public void onPreviewFrame(byte[] data, Camera camera) {
Log.d(TAG, "onPreviewFrame called at: " + System.currentTimeMillis());
Preview.this.invalidate();
}
});
} catch (IOException e) {
e.printStackTrace();
}
}
// Called when the holder is destroyed
public void surfaceDestroyed(SurfaceHolder holder) {
//Log.d(TAG,"Stopping preview in SurfaceDestroyed().");
camera.setPreviewCallback(null);
camera.stopPreview();
camera.release();
camera = null;
}
// Called when holder has changed
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
camera.startPreview();
}
}

The article about Camera from Android API Guide also suffers from the same problem. I could get the preview back after taking pictures by adding two more stuff like following:
1) Add external storage permission in the AndroidManifest.xml file:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
2) Start preview again by calling camera.startPreview(). In your code:
...
Log.d(TAG, "onPictureTaken - jpeg");
camera.startPreview();
....
I'm sure you'll be able to get yours to work in the same way.

Start the CAMERAACTIVITY again in onPictureTaken like this:
// Handles data for jpeg picture
PictureCallback jpegCallback = new PictureCallback() {
public void onPictureTaken(byte[] data, Camera camera) {
FileOutputStream outStream = null;
try {
// Write to SD Card
outStream = new FileOutputStream(String.format("/sdcard/DCIM/queries.jpg",
System.currentTimeMillis()));
outStream.write(data);
outStream.close();
Log.d(TAG, "onPictureTaken - wrote bytes: " + data.length);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
camera.release();
camera = null;
startActivity(new Intent(CAMERAACTIVITY.this, CAMERAACTIVITY.class));
finish();
}
Log.d(TAG, "onPictureTaken - jpeg");
}
};
If you want, you can also use Thread.sleep(2000); so that, the captured image will be shown for 2 seconds and then again camera activity will start.

add
Thread.Sleep(2000);
camera.startPreview();
so that the camera will show the captured image for 2 secs and will restart the camera.