I want a make camera device using libgdx android and i am using this code.
But i am geting NullPointerException at this line Camera.Parameters p = camera.getParameters(); in CameraSurface.java class.
package com.mygdx.cameradevice;
import java.io.IOException;
import android.content.Context;
import android.hardware.Camera;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
public class CameraSurface extends SurfaceView implements SurfaceHolder.Callback {
private Camera camera;
public CameraSurface( Context context ) {
super( context );
// We're implementing the Callback interface and want to get notified
// about certain surface events.
getHolder().addCallback( this );
// We're changing the surface to a PUSH surface, meaning we're receiving
// all buffer data from another component - the camera, in this case.
getHolder().setType( SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS );
}
public void surfaceCreated( SurfaceHolder holder ) {
// Once the surface is created, simply open a handle to the camera hardware.
camera = Camera.open();
}
public void surfaceChanged( SurfaceHolder holder, int format, int width, int height ) {
// This method is called when the surface changes, e.g. when it's size is set.
// We use the opportunity to initialize the camera preview display dimensions.
//System.out.println("ajay");
//camera=Camera.open();
Camera.Parameters p = camera.getParameters();
p.setPreviewSize(width,height);
camera.setParameters(p);
// We also assign the preview display to this surface...
try {
camera.setPreviewDisplay(holder);
} catch( IOException e ) {
e.printStackTrace();
}
}
public void surfaceDestroyed( SurfaceHolder holder ) {
// Once the surface gets destroyed, we stop the preview mode and release
// the whole camera since we no longer need it.
camera.stopPreview();
camera.release();
camera = null;
}
public Camera getCamera() {
return camera;
}
}
I see your code is copyed from https://github.com/libgdx/libgdx/wiki/Integrating-libgdx-and-the-device-camera,
I use the same one,and then i create a project with the help of it,the codes in CameraSurface.java are the same,so maybe there is sth else wrong with.
You can see my simple project https://github.com/54wall/LibgdxAndroidCamera,
to see the difference between yours and mine.I think some key codes in AndroidDeviceCameraController.class.
I hope that would help you!
Related
I'm new in android.
I found previous questions, but are quite old, actually I'm using API 23 or higher.
I'm interested in a way to obtaining a picture from a camera, without displaying the preview and without any touch or interaction of the user.
I used an intent to access to a camera app but don't let me to take a picture automatically in the way I need.
This only let me to use camera app.
Intent intentTakePic = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
if(intentTakePic.resolveActivity(getPackageManager()) != null){
startActivityForResult(intentTakePic, GET_THE_PICTURE);
}
In future I probably need also to record the audio in the same way (without interaction).
Does anyone has suggestion for me ?
You need to use the CameraAPI to take pictures without opening another camera app. https://developer.android.com/guide/topics/media/camera
You'll basically make a camera app.
// in the activity onCreate, but doesn't have to be there
// needs explicit permission
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
requestPermissions(new String[] {Manifest.permission.CAMERA}, 1);
}
}
final Camera camera = Camera.open();
CameraPreview cameraPreview = new CameraPreview(this, camera);
// preview is required. But you can just cover it up in the layout.
FrameLayout previewFL = findViewById(R.id.preview_layout);
previewFL.addView(cameraPreview);
camera.startPreview();
// take picture button
findViewById(R.id.take_picture_button).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
camera.takePicture(null, null, new Camera.PictureCallback() {
#Override
public void onPictureTaken(byte[] data, Camera camera) {
// path of where you want to save it
File pictureFile = new File(getFilesDir() + "/images/pic0");
try {
FileOutputStream fos = new FileOutputStream(pictureFile);
fos.write(data);
fos.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
});
}
});
CameraPreview class
import android.content.Context;
import android.hardware.Camera;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import java.io.IOException;
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
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) {
e.printStackTrace();
}
}
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){
e.printStackTrace();
}
}
}
I found these useful guide:
https://zatackcoder.com/android-camera-2-api-example-without-preview/
https://inducesmile.com/android/android-camera2-api-example-tutorial/
https://github.com/googlesamples/android-Camera2Basic
I'm a complete noob . I've managed to write and understand this code after reading this http://developer.android.com/guide/topics/media/camera.html .
But now i want to get the byte array for preview and then convert it to bitmap . But i want to do this in real time without be forced to save a picture file in storage . Please , help!
Here is my program code.
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
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) {
String TAG = null;
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.
mCamera.setDisplayOrientation(90);
// 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){
String TAG = null;
Log.d(TAG, "Error starting camera preview: " + e.getMessage());
}
}
private PictureCallback mPicture = new PictureCallback(){
#Override
public void onPictureTaken(byte[] data, Camera camera)
{
// TODO: Implement this method
}
};
}
And main activity :
public class MainActivity extends Activity
{ private Camera mCamera;
private CameraPreview mPreview;
int i;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mCamera = getCameraInstance();
mPreview = new CameraPreview(this, mCamera);
FrameLayout preview = (FrameLayout) findViewById(R.id.frame);
preview.addView(mPreview);
}
public static Camera getCameraInstance()
{
Camera c = null;
try
{
c = Camera.open();}
catch (Exception e)
{ System.out.println("blamjjjh");}
return c;
}
public void releasec(){
mCamera.release();
}
#Override
protected void onStop()
{
super.onStop();
releasec();
}
}
As detailed in the Android Developer docs here (which you might have already read), add an implementation of the PictureCallback interface (see the example below) to your Activity. Also you can use BitmapFactory to then convert the byte array that gets passed back to a Bitmap. Then you can use this as required.
NOTE:
I would also read the docs here on handling Bitmaps efficiently in relation to memory as you might get OutOfMemory errors if you're manipulating Bitmaps.
private PictureCallback mPicture = new PictureCallback() {
#Override
public void onPictureTaken(byte[] data, Camera camera) {
//create a Bitmap from the byte array
Bitmap bitmap = BitmapFactory.decodeByteArray(data , 0, data.length);
//use your Bitmap
}
};
You then need to pass this into the takePicture() method against your camera instance e.g.
// Add a listener to the Capture button
Button captureButton = (Button) findViewById(id.button_capture);
captureButton.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
// get an image from the camera
mCamera.takePicture(null, null, mPicture);
}
}
);
Hope this helps! :-)
New to Android programming here.
I have had a look around and have found this to be a common issue, but I don't really see an easy fix... I am trying to run the following code on a Nexus 7 (have tried AVD & physical device) with no luck whatsoever. It seems to be the:
camera.setPreviewDisplay(SurfaceHolder);
But I could be wrong. Here is the current code:
public class MainActivity extends Activity implements SurfaceHolder.Callback{
Camera camera;
SurfaceView surfaceView;
SurfaceHolder surfaceHolder;
boolean previewing = false;;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.cameralayout);
getWindow().setFormat(PixelFormat.UNKNOWN);
surfaceView = (SurfaceView)findViewById(R.id.surfaceview);
surfaceHolder = surfaceView.getHolder();
surfaceHolder.addCallback(this);
}
public void onClick() {
// TODO Auto-generated method stub
if(!previewing){
camera = Camera.open();
if (camera != null){
try {
camera.setPreviewDisplay(surfaceHolder);
camera.startPreview();
previewing = true;
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
Any ideas folks? Thank you for your help!
From android documentation about Camera.open()
Creates a new Camera object to access the first back-facing camera on
the device. If the device does not have a back-facing camera, this
returns null.
It gives you only an access to back-facing Camera.
I am trying to run the following code on a Nexus 7
Camera.open() returns null because Nexus 7 doesn't have a back camera, only a front camera.
You could try this method
public Camera getCamera()
{
for(int i = 0; i < Camera.getNumberOfCameras(); i++)
return Camera.open(i);
return null;
}
To apply,
camera = getCamera();
I have an application using OpenCV for Android and was wondering if it was possible to enable the camera's LED.
Currently my camera is set up using the following code:
camera = new VideoCapture(Highgui.CV_CAP_ANDROID);
All examples I've seen which enable the LED Flash require Camera.Parameters which I don't have access to with this camera setup.
Is there any simple way to enable the LED without switching to using the basic Camera class for my videostream, as this tends to be much slower.
Thanks for any help in advance.
In OpenCV for Android 2.4, you can do this,
mCamera.set(
Highgui.CV_CAP_PROP_ANDROID_FLASH_MODE,
Highgui.CV_CAP_ANDROID_FLASH_MODE_ON
);
Other options are: CV_CAP_ANDROID_FLASH_MODE_AUTO, CV_CAP_ANDROID_FLASH_MODE_OFF, CV_CAP_ANDROID_FLASH_MODE_TORCH andCV_CAP_ANDROID_FLASH_MODE_REDEYE.
However, using this causes the application to automatically close on my tablet (Asus TF101). Hopefully it works on others.
You can use extends JavaCameraView
public class Tutorial2View extends JavaCameraView{
private static final String TAG = "Sample::Tutorial2View";
private Context myreference;
private static boolean isFlashLightON = false;
public Tutorial2View(Context context, AttributeSet attrs) {
super(context, attrs);
this.myreference = context;
}
public List<String> getEffectList() {
return mCamera.getParameters().getSupportedColorEffects();
}
public boolean isEffectSupported() {
return (mCamera.getParameters().getColorEffect() != null);
}
public String getEffect() {
return mCamera.getParameters().getColorEffect();
}
public void setEffect(String effect) {
Camera.Parameters params = mCamera.getParameters();
params.setColorEffect(effect);
mCamera.setParameters(params);
}
public List<Size> getResolutionList() {
return mCamera.getParameters().getSupportedPreviewSizes();
}
public void setResolution(Size resolution) {
disconnectCamera();
mMaxHeight = resolution.height;
mMaxWidth = resolution.width;
connectCamera(getWidth(), getHeight());
}
public Size getResolution() {
return mCamera.getParameters().getPreviewSize();
}
// Setup the camera
public void setupCameraFlashLight() {
Camera camera = mCamera;
if (camera != null) {
Parameters params = camera.getParameters();
if (params != null) {
if (isFlashLightON) {
isFlashLightON = false;
params.setFlashMode(Parameters.FLASH_MODE_OFF);
camera.setParameters(params);
camera.startPreview();
} else {
isFlashLightON = true;
params.setFlashMode(Parameters.FLASH_MODE_TORCH);
camera.setParameters(params);
camera.startPreview();
}
}
}
}
}
Call setupCameraFlashLight(); to ON OFF the LED light
It seems there is no easy way to do this. The only option is to use the default Android Camera class and take the slight performance hit.
If you use JavaCameraView you can simply add on the end two methods to your JavaCameraView.java class:
public void turnOffTheFlash() {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(params.FLASH_MODE_OFF);
mCamera.setParameters(params);
}
public void turnOnTheFlash() {
Camera.Parameters params = mCamera.getParameters();
params.setFlashMode(params.FLASH_MODE_TORCH);
mCamera.setParameters(params);
}
You can run them in your activity as follow:
private JavaCameraView javaCameraView;
javaCameraView.turnOnTheFlash();
javaCameraView.turnOffTheFlash();
Mayby you should use FLASH_MODE_ON rather than FLASH_MODE_TORCH.
It works for my on OpenCV 2.4.9.
I'm using a Nexus One and the Camera displays horizontal when it should be vertical and vice versa. I've no idea what's wrong. The code works fine on a HTC tattoo. Anyone have any idea what's wrong?
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();
try {
mCamera.setPreviewDisplay(holder);
} catch (IOException 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.
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 = mCamera.getParameters();
parameters.setPreviewSize(800, 480);
mCamera.setParameters(parameters);
mCamera.startPreview();
}
Got it working. I added..
parameters.set("orientation", "portrait");
CommonsWare gave me the idea it was that kind of issue thanks man :)