Develop Reference

Use camera but dont want to take photo

I want to use camera in my app but dont want to take photo, actually I am making a app i.e transparent screen, in this I want to show transparent wallpaper i.e I have to start camera for this and i dont want to take images for this
I tried all these codes but have n't got the desirable results. Can anyone suggest what must i do?
used this permission in all cases
<uses-permission android:name="android.permission.CAMERA"/>
Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
startActivity(intent);
Intent intent = new Intent(Intent.ACTION_CAMERA_BUTTON, null);
startActivity(intent);
Intent intent = new Intent(android.provider.MediaStore.INTENT_ACTION_STILL_IMAGE_CAMERA);
startActivity(intent);
Update 1:
I tried this code it showing camera in not correct way, its diverting the preview to right kindly look over this updated code and tell wht amendment i can make over this
public class MainActivity extends Activity {
private Preview mPreview;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
try{
requestWindowFeature(Window.FEATURE_NO_TITLE);
// Create our Preview view and set it as the content of our activity.
mPreview = new Preview(this);
setContentView(mPreview);
}catch(Exception e){
e.printStackTrace();
}
}
******************************************************************************************
public class Preview extends SurfaceView implements SurfaceHolder.Callback {
SurfaceHolder mHolder;
Camera mCamera;
Preview(Context context) {
super(context);
// Install a SurfaceHolder.Callback so we get notified when the
// underlying surface is created and destroyed.
try{
mHolder = getHolder();
mHolder.addCallback(this);
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}catch(Exception e){
e.printStackTrace();
}
}
public void surfaceCreated(SurfaceHolder holder) {
// The Surface has been created, acquire the camera and tell it where
// to draw.
try{
if(mCamera!=null){
mCamera.release();
mCamera=null;
}
mCamera = Camera.open();
Log.i("Camera", "Camera is opened");
mCamera.setPreviewDisplay(holder);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
// Surface will be destroyed when we return, so stop the preview.
// Because the CameraDevice object is not a shared resource, it's very
// important to release it when the activity is paused.
try{
mCamera.stopPreview();
mCamera.release();
mCamera = null;
}catch(Exception e){
e.printStackTrace();
}
}
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
// Now that the size is known, set up the camera parameters and begin
// the preview.
try{
Parameters parameters = mCamera.getParameters();
List<Camera.Size> sizes = parameters.getSupportedPreviewSizes();
Camera.Size cs = sizes.get(0);
parameters.setPreviewSize(cs.width, cs.height);
mCamera.setParameters(parameters);
mCamera.startPreview();
}catch(Exception e){
e.printStackTrace();
}
}
}

You need to use surfaceView for this. Here is an example:
public class CameraPreview extends Activity {
private Preview mPreview;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Hide the window title.
requestWindowFeature(Window.FEATURE_NO_TITLE);
// Create our Preview view and set it as the content of our activity.
mPreview = new Preview(this);
setContentView(mPreview);
}
}
public class Preview extends SurfaceView implements SurfaceHolder.Callback {
SurfaceHolder mHolder;
Camera mCamera;
Preview(Context context) {
super(context);
// 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, acquire the camera and tell it where
// to draw.
mCamera = Camera.open();
mCamera.setPreviewDisplay(holder);
}
public void surfaceDestroyed(SurfaceHolder holder) {
// Surface will be destroyed when we return, so stop the preview.
// Because the CameraDevice object is not a shared resource, it's very
// important to release it when the activity is paused.
mCamera.stopPreview();
mCamera = null;
}
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
// Now that the size is known, set up the camera parameters and begin
// the preview.
Camera.Parameters parameters = camera.getParameters();
List<Camera.Size> sizes = parameters.getSupportedPreviewSizes();
Camera.Size cs = sizes.get(0);
parameters.setPreviewSize(cs.width, cs.height);
camera.setParameters(parameters);
mCamera.startPreview();
}
}

I used this code and it worked...
<uses-permission android:name="android.permission.CAMERA"/>
public class MainActivity extends Activity {
private Preview mPreview;
/** Called when the activity is first created. */
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
try{
requestWindowFeature(Window.FEATURE_NO_TITLE);
// Create our Preview view and set it as the content of our activity.
mPreview = new Preview(this);
setContentView(mPreview);
}catch(Exception e){
e.printStackTrace();
}
}
}
*****************************************************************************************
public class Preview extends SurfaceView implements SurfaceHolder.Callback {
SurfaceHolder mHolder;
Camera mCamera;
Preview(Context context) {
super(context);
// Install a SurfaceHolder.Callback so we get notified when the
// underlying surface is created and destroyed.
try {
mHolder = getHolder();
mHolder.addCallback(this);
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
} catch (Exception e) {
e.printStackTrace();
}
}
public void surfaceCreated(SurfaceHolder holder) {
// The Surface has been created, acquire the camera and tell it where
// to draw.
try {
if (mCamera != null) {
mCamera.release();
mCamera = null;
}
mCamera = Camera.open();
Log.i("Camera", "Camera is opened");
mCamera.setPreviewDisplay(holder);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
// Surface will be destroyed when we return, so stop the preview.
// Because the CameraDevice object is not a shared resource, it's very
// important to release it when the activity is paused.
try {
mCamera.stopPreview();
mCamera.release();
mCamera = null;
} catch (Exception e) {
e.printStackTrace();
}
}
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
// Now that the size is known, set up the camera parameters and begin
// the preview.
try {
Camera.Parameters parameters = mCamera.getParameters();
parameters.set("orientation", "portrait");
mCamera.setDisplayOrientation(90);
List<Camera.Size> sizes = parameters.getSupportedPreviewSizes();
Camera.Size cs = sizes.get(0);
parameters.setPreviewSize(cs.width, cs.height);
mCamera.setParameters(parameters);
mCamera.startPreview();
} catch (Exception e) {
e.printStackTrace();
}
}
}

Surface View Camera Preview

Having a little trouble getting my SurfaceView to show my camera preview. I've looked at some questions on here and Google'd some tuts but I think it may be a small error on my end that I'm just not seeing.
Code
public class RoofPitchActivity extends Activity implements SensorEventListener {
...
private SurfaceView mSurfaceView;
private SurfaceHolder mSurfaceHolder;
private Camera mCamera;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_roof_pitch);
initViews();
}
private void initViews() {
...
Preview preview = new Preview(this);
mCamera = Camera.open();
preview.setCamera(mCamera);
}
...
...
class Preview extends ViewGroup implements SurfaceHolder.Callback {
public Preview(Context context) {
super(context);
mSurfaceView = (SurfaceView) findViewById(R.id.preview);
mSurfaceView = new SurfaceView(context);
addView(mSurfaceView);
mSurfaceHolder = mSurfaceView.getHolder();
mSurfaceHolder.addCallback(this);
}
public void setCamera(Camera camera) {
if (mCamera == camera) {
return;
}
stopPreviewAndFreeCamera();
mCamera = camera;
if (mCamera != null) {
requestLayout();
try {
mCamera.setPreviewDisplay(mSurfaceHolder);
} catch (IOException e) {
e.printStackTrace();
}
mCamera.startPreview();
}
}
private void stopPreviewAndFreeCamera() {
if (mCamera != null) {
mCamera.stopPreview();
mCamera.release();
mCamera = null;
}
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
mCamera.startPreview();
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
Camera.Parameters parameters = mCamera.getParameters();
parameters.setPreviewSize(mSurfaceView.getWidth(), mSurfaceView.getHeight());
requestLayout();
mCamera.setParameters(parameters);
mCamera.startPreview();
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
if (mCamera != null) {
mCamera.stopPreview();
}
}
#Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
}
}
}
So when the activity is launched the SurfaceView is black. The camera does not appear to be rendering the preview onto the SurfaceView. I'm sure there's something small I'm missing, or maybe it's just a fundemental misunderstanding of how this works. A fresh set of eyes with a little explanation would be very much appreciated. Thanks

So the answer to my question ended up being device specific. The code was acceptable but my device I'm using to debug is a Nexus 7. This means the camera is front facing and the normal call to the camera does not work. An interesting and funny read about this can be found in this article
Camera.open();
does not work. You must use
Camera.open(0);
So my code ended up with a conditional check for the camera and now it works fine.
Like so
public void setCamera() {
stopPreviewAndFreeCamera();
PackageManager pm = getPackageManager();
boolean backCamera = pm.hasSystemFeature(PackageManager.FEATURE_CAMERA);
boolean frontCamera = pm.hasSystemFeature(PackageManager.FEATURE_CAMERA_FRONT);
if (frontCamera) {
mCamera = Camera.open(0);
} else if (backCamera) {
mCamera = Camera.open();
}
if (mCamera != null) {
Camera.Parameters parameters = mCamera.getParameters();
parameters.setPreviewSize(mSurfaceView.getWidth(), mSurfaceView.getHeight());
requestLayout();
try {
mCamera.setParameters(parameters);
mCamera.setPreviewDisplay(mSurfaceHolder);
} catch (IOException e) {
e.printStackTrace();
}
mCamera.startPreview();
}
}

Exit onPreviewFrame and notify user

I am working the onPreviewFrame(byte[] data, Camera camera) on Android. Within the onPreviewFrame I do some image processing. At a point inside the onPreviewFrame I want to stop the preview (I know the point by an if statement) and play a sound - perhaps the phone ringtome. I think you can not play a sound in the preview.
How do I exit the onPreviewFrame and where do I add the code for playing the sound?
Is it on Surface Destroyed?
Here is my code:
public class MyCameraPreview extends Activity {
private Preview mPreview;
public TextView results;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Hide the window title.
requestWindowFeature(Window.FEATURE_NO_TITLE);
// Create our Preview view and set it as the content of our activity.
mPreview = new Preview(this);
setContentView(mPreview);
}
}
class Preview extends SurfaceView implements SurfaceHolder.Callback, PreviewCallback {
SurfaceHolder mHolder;
Camera mCamera;
public TextView results;
public TextView txt;
private Parameters parameters;
//this variable stores the camera preview size
private Size previewSize;
//this array stores the pixels as hexadecimal pairs
private int[] pixels;
public int[] argb8888;
Preview(Context context) {
super(context);
// 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, acquire the camera and tell it where
// to draw.
mCamera = Camera.open();
try {
mCamera.setPreviewDisplay(holder);
//sets the camera callback to be the one defined in this class
mCamera.setPreviewCallback(this);
parameters = mCamera.getParameters();
parameters.setZoom(parameters.getMaxZoom());
mCamera.setParameters(parameters);
parameters = mCamera.getParameters();
previewSize = parameters.getPreviewSize();
pixels = new int[previewSize.width * previewSize.height];
} catch (IOException exception) {
mCamera.release();
mCamera = null;
// TODO: add more exception handling logic here
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
// Surface will be destroyed when we return, so stop the preview.
// Because the CameraDevice object is not a shared resource, it's very
// important to release it when the activity is paused.
mCamera.stopPreview();
mCamera.release();
mCamera = null;
}
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
// Now that the size is known, set up the camera parameters and begin
// the preview.
parameters.setPreviewSize(w, h);
//set the camera's settings
mCamera.setParameters(parameters);
mCamera.startPreview();
}
#Override
public void onPreviewFrame(byte[] data, Camera camera) {
Do some image processing.
If condition == true {
Exit the preview and then play the ringtone and exit the application.
}
}

In Preview you can add a definition of a listener and use it to not doint the sound in the Preview.
Something like this :
public static interface OnPreviewListener {
void onImageMakeSound();
}
public void setListener(OnPreviewListener listener) {
this.listener = listener;
}
Then in your onPreviewFrame method :
#Override
public void onPreviewFrame(byte[] data, Camera camera) {
if (countFrame > 5) {
imageBytes = data;
countFrame = 0;
if (listener != null)
listener.onImageMakeSound();
}
countFrame++;
camera.addCallbackBuffer(data);
return;
}
In your activity, that must implements OnPreviewListener :
#Override
public void onImageMakeSound() {
alarmSoundOn();
}

camera preview on lockscreen

I want add a take picture function in lockscreen , and I need to open the preview on screen , but it's fail all the time , logcat say the Error is about "setPreviewWindow - Null ANativeWindow passed to setPreviewWindow" and "startPreview - Preview not started. Preview in progress flag set"
In keyguard_screen_tab_unlock.xml after the digital clock view, put
<FrameLayout
android:id="#+id/mPreview"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
In LockScreen.java constructor:
FrameLayout mFrameLayout = (FrameLayout)findViewById(R.id.mPreview);
SurfacePreview preview = new SurfacePreview(mContext);
preview.setZOrderOnTop(true);
mFrameLayout.addView(preview);
SurfacePreview class :
public class SurfacePreview extends SurfaceView implements SurfaceHolder.Callback {
private SurfaceHolder mSurfaceHolder;
SurfacePreview(Context context) {
super(context);
mSurfaceHolder = this.getHolder();
mSurfaceHolder.addCallback(this);
mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
public void surfaceCreated(SurfaceHolder holder) {
mCamera = Camera.open(CameraInfo.CAMERA_FACING_BACK);
try {
mCamera.setPreviewDisplay(holder);
} catch (IOException e) {
e.printStackTrace();
}
mCamera.startPreview();
}
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
Camera.Parameters parameters = mCamera.getParameters();
mCamera.setParameters(parameters);
mCamera.setDisplayOrientation(90);
}
public void surfaceDestroyed(SurfaceHolder holder) {
mCamera.release();
}
}
Anyone kown how to resolve this issue and start prview on LockScreen? Thanks a lot.

Example of Camera preview using SurfaceTexture in Android

I am trying to render camera preview using SurfaceTexture. I read the document but unable to understand how it works.
Can anyone provide one sample example(very basic one) or link which uses SurfaceTexture to preview camera. I googled this but not found what I am looking for.
Thanks in advance.

If you want to use the Camera with TextureSurface you can implement SurfaceTextureListener interface. You'll have to implement 4 methods:
1) onSurfaceTextureAvailable - Here you setup your camera
2)onSurfaceTextureSizeChanged - In your case, the Android's camera will handle this method
3)onSurfaceTextureDestroyed - Here you destroy all camera stuff.
4) onSurfaceTextureUpdated- Update your texture here when you have something to change!
Check the example below:
public class MainActivity extends Activity implements SurfaceTextureListener{
private Camera mCamera;
private TextureView mTextureView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mTextureView = new TextureView(this);
mTextureView.setSurfaceTextureListener(this);
setContentView(mTextureView);
}
#Override
public void onSurfaceTextureAvailable(SurfaceTexture surface, int width, int height) {
mCamera = Camera.open();
Camera.Size previewSize = mCamera.getParameters().getPreviewSize();
mTextureView.setLayoutParams(new FrameLayout.LayoutParams(
previewSize.width, previewSize.height, Gravity.CENTER));
try {
mCamera.setPreviewTexture(surface);
} catch (IOException t) {
}
mCamera.startPreview();
}
#Override
public void onSurfaceTextureSizeChanged(SurfaceTexture surface, int width, int height) {
// Ignored, the Camera does all the work for us
}
#Override
public boolean onSurfaceTextureDestroyed(SurfaceTexture surface) {
mCamera.stopPreview();
mCamera.release();
return true;
}
#Override
public void onSurfaceTextureUpdated(SurfaceTexture surface) {
// Update your view here!
}
}
Two more things: Don't forget to add the camera permissions in your project's manifest and the SurfaceTexture is available from API 11.

public class VideoCapture extends Activity implements OnClickListener, SurfaceHolder.Callback {
MediaRecorder recorder;
SurfaceHolder holder;
boolean recording = false;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
recorder = new MediaRecorder();
initRecorder();
SurfaceView cameraView = new SurfaceView(this);
holder = cameraView.getHolder();
holder.addCallback(this);
holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
cameraView.setClickable(true);
cameraView.setOnClickListener(this);
}
private void initRecorder() {
recorder.setAudioSource(MediaRecorder.AudioSource.DEFAULT);
recorder.setVideoSource(MediaRecorder.VideoSource.DEFAULT);
CamcorderProfile cpHigh = CamcorderProfile
.get(CamcorderProfile.QUALITY_HIGH);
recorder.setProfile(cpHigh);
recorder.setOutputFile("/sdcard/videocapture_example.mp4");
recorder.setMaxDuration(50000); // 50 seconds
recorder.setMaxFileSize(5000000); // Approximately 5 megabytes
}
private void prepareRecorder() {
recorder.setPreviewDisplay(holder.getSurface());
try {
recorder.prepare();
} catch (IllegalStateException e) {
e.printStackTrace();
finish();
} catch (IOException e) {
e.printStackTrace();
finish();
}
}
public void onClick(View v) {
if (recording) {
recorder.stop();
recording = false;
// Let's initRecorder so we can record again
initRecorder();
prepareRecorder();
} else {
recording = true;
recorder.start();
}
}
public void surfaceCreated(SurfaceHolder holder) {
prepareRecorder();
}
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
}
public void surfaceDestroyed(SurfaceHolder holder) {
if (recording) {
recorder.stop();
recording = false;
}
recorder.release();
finish();
}
}