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android - how to capture an image in background without using the camera application

I have an android app which consists of a Button.
When you click on Button, an image should be captured from the camera without opening the camera application (the image should be captured in background).
How to implement this feature?
Any suggestions will be of great help.
Thanks a lot in advance.

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by (71.8m points)

Here is my whole working project of How to capture image in background without SurfaceView.

// You can start your service to capturing image wherever you want not should from activity.

also need to ask need permission in your Activity

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && !Settings.canDrawOverlays(this)) {
Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION,
Uri.parse("package:" + getPackageName()));
startActivityForResult(intent, APP_PERMISSION_REQUEST);
} 

handle intent in click or where you needed

Intent front_translucent = new Intent(getApplication()
                        .getApplicationContext(), CameraService.class);
                front_translucent.putExtra("Front_Request", true);
                front_translucent.putExtra("Quality_Mode",
                        camCapture.getQuality());
                getApplication().getApplicationContext().startService(
                        front_translucent);


public class CamerService extends Service implements
        SurfaceHolder.Callback {

    // Camera variables
    // a surface holder
    // a variable to control the camera
    private Camera mCamera;
    // the camera parameters
    private Parameters parameters;
    private Bitmap bmp;
    FileOutputStream fo;
    private String FLASH_MODE;
    private int QUALITY_MODE = 0;
    private boolean isFrontCamRequest = false;
    private Camera.Size pictureSize;
    SurfaceView sv;
    private SurfaceHolder sHolder;
    private WindowManager windowManager;
    WindowManager.LayoutParams params;
    public Intent cameraIntent;
    SharedPreferences pref;
    Editor editor;
    int width = 0, height = 0;

    /** Called when the activity is first created. */
    @Override
    public void onCreate() {
        super.onCreate();

    }

    private Camera openFrontFacingCameraGingerbread() {
        if (mCamera != null) {
            mCamera.stopPreview();
            mCamera.release();
        }
        int cameraCount = 0;
        Camera cam = null;
        Camera.CameraInfo cameraInfo = new Camera.CameraInfo();
        cameraCount = Camera.getNumberOfCameras();
        for (int camIdx = 0; camIdx < cameraCount; camIdx++) {
            Camera.getCameraInfo(camIdx, cameraInfo);
            if (cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
                try {
                    cam = Camera.open(camIdx);
                } catch (RuntimeException e) {
                    Log.e("Camera",
                            "Camera failed to open: " + e.getLocalizedMessage());
                    /*
                     * Toast.makeText(getApplicationContext(),
                     * "Front Camera failed to open", Toast.LENGTH_LONG)
                     * .show();
                     */
                }
            }
        }
        return cam;
    }

    private void setBesttPictureResolution() {
        // get biggest picture size
        width = pref.getInt("Picture_Width", 0);
        height = pref.getInt("Picture_height", 0);

        if (width == 0 | height == 0) {
            pictureSize = getBiggesttPictureSize(parameters);
            if (pictureSize != null)
                parameters
                        .setPictureSize(pictureSize.width, pictureSize.height);
            // save width and height in sharedprefrences
            width = pictureSize.width;
            height = pictureSize.height;
            editor.putInt("Picture_Width", width);
            editor.putInt("Picture_height", height);
            editor.commit();

        } else {
            // if (pictureSize != null)
            parameters.setPictureSize(width, height);
        }
    }

    private Camera.Size getBiggesttPictureSize(Camera.Parameters parameters) {
        Camera.Size result = null;

        for (Camera.Size size : parameters.getSupportedPictureSizes()) {
            if (result == null) {
                result = size;
            } else {
                int resultArea = result.width * result.height;
                int newArea = size.width * size.height;

                if (newArea > resultArea) {
                    result = size;
                }
            }
        }

        return (result);
    }

    /** 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;
        }
    }

    /** Check if this device has front camera */
    private boolean checkFrontCamera(Context context) {
        if (context.getPackageManager().hasSystemFeature(
                PackageManager.FEATURE_CAMERA_FRONT)) {
            // this device has front camera
            return true;
        } else {
            // no front camera on this device
            return false;
        }
    }

    Handler handler = new Handler();

    private class TakeImage extends AsyncTask<Intent, Void, Void> {

        @Override
        protected Void doInBackground(Intent... params) {
            takeImage(params[0]);
            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
        }
    }

    private synchronized void takeImage(Intent intent) {

        if (checkCameraHardware(getApplicationContext())) {
            Bundle extras = intent.getExtras();
            if (extras != null) {
                String flash_mode = extras.getString("FLASH");
                FLASH_MODE = flash_mode;

                boolean front_cam_req = extras.getBoolean("Front_Request");
                isFrontCamRequest = front_cam_req;

                int quality_mode = extras.getInt("Quality_Mode");
                QUALITY_MODE = quality_mode;
            }

            if (isFrontCamRequest) {

                // set flash 0ff
                FLASH_MODE = "off";
                // only for gingerbread and newer versions
                if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.GINGERBREAD) {

                    mCamera = openFrontFacingCameraGingerbread();
                    if (mCamera != null) {

                        try {
                            mCamera.setPreviewDisplay(sv.getHolder());
                        } catch (IOException e) {
                            handler.post(new Runnable() {

                                @Override
                                public void run() {
                                    Toast.makeText(getApplicationContext(),
                                            "API dosen't support front camera",
                                            Toast.LENGTH_LONG).show();
                                }
                            });

                            stopSelf();
                        }
                        Camera.Parameters parameters = mCamera.getParameters();  
                        pictureSize = getBiggesttPictureSize(parameters);
                        if (pictureSize != null)
                            parameters
                                    .setPictureSize(pictureSize.width, pictureSize.height);

                        // set camera parameters
                        mCamera.setParameters(parameters);
                        mCamera.startPreview();
                        mCamera.takePicture(null, null, mCall);

                        // return 4;

                    } else {
                        mCamera = null;
                        handler.post(new Runnable() {

                            @Override
                            public void run() {
                                Toast.makeText(
                                        getApplicationContext(),
                                        "Your Device dosen't have Front Camera !",
                                        Toast.LENGTH_LONG).show();
                            }
                        });

                        stopSelf();
                    }
                    /*
                     * sHolder = sv.getHolder(); // tells Android that this
                     * surface will have its data // constantly // replaced if
                     * (Build.VERSION.SDK_INT < 11)
                     * 
                     * sHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS)
                     */
                } else {
                    if (checkFrontCamera(getApplicationContext())) {
                        mCamera = openFrontFacingCameraGingerbread();

                        if (mCamera != null) {

                            try {
                                mCamera.setPreviewDisplay(sv.getHolder());
                            } catch (IOException e) {
                                handler.post(new Runnable() {

                                    @Override
                                    public void run() {
                                        Toast.makeText(
                                                getApplicationContext(),
                                                "API dosen't support front camera",
                                                Toast.LENGTH_LONG).show();
                                    }
                                });

                                stopSelf();
                            }
                            Camera.Parameters parameters = mCamera.getParameters();  
                            pictureSize = getBiggesttPictureSize(parameters);
                            if (pictureSize != null)
                                parameters
                                        .setPictureSize(pictureSize.width, pictureSize.height);

                            // set camera parameters
                            mCamera.setParameters(parameters);
                            mCamera.startPreview();
                            mCamera.takePicture(null, null, mCall);
                            // return 4;

                        } else {
                            mCamera = null;
                            /*
                             * Toast.makeText(getApplicationContext(),
                             * "API dosen't support front camera",
                             * Toast.LENGTH_LONG).show();
                             */
                            handler.post(new Runnable() {

                                @Override
                                public void run() {
                                    Toast.makeText(
                                            getApplicationContext(),
                                            "Your Device dosen't have Front Camera !",
                                            Toast.LENGTH_LONG).show();

                                }
                            });

                            stopSelf();

                        }
                        // Get a surface
                        /*
                         * sHolder = sv.getHolder(); // tells Android that this
                         * surface will have its data // constantly // replaced
                         * if (Build.VERSION.SDK_INT < 11)
                         * 
                         * sHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS
                         * );
                         */
                    }

                }

            } else {

                if (mCamera != null) {
                    mCa

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