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Create your own application for the camera + Automatic image capture

I created my own application for the camera. And when I press the button, she takes a photo and saves it in galari. I want to take a picture without previewing and without clicking a button.

My main activity class.

package themiya.camera.android; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; import android.app.Activity; import android.content.Context; import android.content.pm.PackageManager; import android.hardware.Camera; import android.hardware.Camera.PictureCallback; import android.net.Uri; import android.os.Bundle; import android.os.Environment; import android.provider.MediaStore; import android.view.View; import android.widget.Button; import android.widget.FrameLayout; import android.widget.Toast; public class CameraActivity extends Activity { private Camera mCamera; private CameraPreview mPreview; public static final int MEDIA_TYPE_IMAGE = 1; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); Button captureButton = (Button) findViewById(R.id.button_capture); System.out.println("Starting!"); // 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); FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview); preview.addView(mPreview); final PictureCallback mPicture = new PictureCallback() { public void onPictureTaken(byte[] data, Camera camera) { File pictureFile = getOutputMediaFile(MEDIA_TYPE_IMAGE); if (pictureFile == null){ return; } try { FileOutputStream fos = new FileOutputStream(pictureFile); fos.write(data); fos.close(); MediaStore.Images.Media.insertImage(getContentResolver(), pictureFile.getAbsolutePath(), pictureFile.getName(), pictureFile.getName()); } catch (FileNotFoundException e) { } catch (IOException e) { } } }; // Add a listener to the Capture button captureButton.setOnClickListener( new View.OnClickListener() { public void onClick(View v) { // get an image from the camera System.out.println("Photo Taking!"); mCamera.takePicture(null, null, mPicture); } } ); } /** 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 } @Override protected void onPause() { super.onPause(); releaseCamera(); // release the camera immediately on pause event } private void releaseCamera(){ if (mCamera != null){ mCamera.release(); // release the camera for other applications mCamera = null; } } /** Create a File for saving an image or video */ private 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()){ 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; } }

And a preview class.

 package themiya.camera.android; import android.content.Context; import android.hardware.Camera; import android.view.SurfaceHolder; import android.view.SurfaceView; public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback{ private SurfaceHolder mHolder; private Camera mCamera; public CameraPreview(Context context,Camera camera) { super(context); mCamera = camera; /*SurfaceView view = new SurfaceView(this); c.setPreviewDisplay(view.getHolder()); c.startPreview(); c.takePicture(shutterCallback, rawPictureCallback, jpegPictureCallback); * */ // 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 surfaceChanged(SurfaceHolder holder, int format, int width, int height) { // TODO Auto-generated method stub 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){ } } public void surfaceCreated(SurfaceHolder holder) { // TODO Auto-generated method stub } public void surfaceDestroyed(SurfaceHolder holder) { // TODO Auto-generated method stub } }

In an activity class, the on click method is as follows.

 captureButton.setOnClickListener( new View.OnClickListener() { public void onClick(View v) { // get an image from the camera System.out.println("Photo Taking!"); mCamera.takePicture(null, null, mPicture); } } );

And when I delete this part of the listener and put only

 mCamera.takePicture(null, null, mPicture);

application crashes. I think this may be due to the delay that the application takes to open the camera. Therefore, the code tries to get a photo before opening the camera. Also wait (10000); not working for me.

And also I want to take a picture without preview. To my knowledge, I have to change the preview class to do this. But I don’t know how to do it right.

Can anyone help me with this asp.

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3 answers

Ok, I found the answer to take a picture automatically. Adding as a comment to use others.

 final Timer t = new Timer(); t.schedule(new TimerTask() { @Override public void run() { mCamera.takePicture(null, null, mPicture); t.cancel(); } },5000);
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the trick is to provide the Camera SurfaceView class, which is not part of the view hierarchy. The following code is from one of my applications where I used this method to display my own

 @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); } @Override protected void onPause() { super.onPause(); if (mCamera != null) { mCamera.stopPreview(); mCamera.release(); mCamera = null; } } @Override protected void onResume() { super.onResume(); mCamera = Camera.open(); startPreview(); } private void startPreview() { if (mCamera != null) { mCamera.stopPreview(); try { mCamera.setPreviewDisplay(new SurfaceView(this).getHolder()); } catch (IOException e) { e.printStackTrace(); } mCamera.setPreviewCallbackWithBuffer(this); Camera.Parameters parameters = mCamera.getParameters(); parameters.setPreviewSize(IMAGE_W, IMAGE_H); mCamera.setParameters(parameters); PixelFormat p = new PixelFormat(); PixelFormat.getPixelFormatInfo(parameters.getPreviewFormat(), p); int bufSize = (IMAGE_W * IMAGE_H * p.bitsPerPixel) / 8; mCamera.addCallbackBuffer(new byte[bufSize]); mCamera.startPreview(); } } public void onPreviewFrame(final byte[] data, Camera camera) { if (mCamera == null) { return; } mCamera.addCallbackBuffer(data); } }
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its simple to create another method with a timer variable with a 10,000 delay that will complete the preview activity, then you will be ready. The logic is that this method will work 5 seconds after the timer 1 operation.

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Source: https://habr.com/ru/post/911574/

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