Android: Take Photo Without User Interface
I am interested in writing an app for android where after a certain event in the app a photo is automatically taken using the camera on the android.
Things I need:
No Preview of photo
No Button for User to press to take the photo
Just run the operation to take a photo and store it to the album.
here is some code i tried from a tutorial online:
public void snap(){
mCamera = Camera.open();
SurfaceView sv = new SurfaceView(getApplicationContext());
try {
mCamera.setPreviewDisplay(sv.getHolder());
parameters = mCamera.getParameters();
//set camera parameters
mCamera.setParameters(parameters);
mCamera.startPreview();
mCamera.takePicture(null, null, mCall);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//Get a surface
sHolder = sv.getHolder();
}
Camera.PictureCallback mCall = new Camera.PictureCallback()
{
public void onPictureTaken(byte[] data, Camera camera)
{
//decode the data obtained by the camera into a Bitmap
FileOutputStream outStream = null;
try{
outStream = new FileOutputStream("/sdcard/Image.jpg");
outStream.write(data);
outStream.close();
} catch (FileNotFoundException e){
Log.d("CAMERA", e.getMessage());
} catch (IOException e){
Log.d("CAMERA", e.getMessage());
}
}
};
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
along with the logcat of what it did
11-24 01:54:37.738: E/AndroidRuntime(6971): FATAL EXCEPTION: main
11-24 01:54:37.738: E/AndroidRuntime(6971): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.udptest/com.example.udptest.Main}: java.lang.RuntimeException: takePicture failed
11-24 01:54:37.738: E/AndroidRuntime(6971): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2308)
11-24 01:54:37.738: E/AndroidRuntime(6971): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2358)
11-24 01:54:37.738: E/AndroidRuntime(6971): at android.app.ActivityThread.access$600(ActivityThread.java:153)
11-24 01:54:37.738: E/AndroidRuntime(6971): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1247)
11-24 01:54:37.738: E/AndroidRuntime(6971): at android.os.Handler.dispatchMessage(Handler.java:99)
11-24 01:54:37.738: E/AndroidRuntime(6971): at android.os.Looper.loop(Looper.java:137)
11-24 01:54:37.738: E/AndroidRuntime(6971): at android.app.ActivityThread.main(ActivityThread.java:5227)
11-24 01:54:37.738: E/AndroidRuntime(6971): at java.lang.reflect.Method.invokeNative(Native Method)
11-24 01:54:37.738: E/AndroidRuntime(6971): at java.lang.reflect.Method.invoke(Method.java:511)
11-24 01:54:37.738: E/AndroidRuntime(6971): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:795)
11-24 01:54:37.738: E/AndroidRuntime(6971): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:562)
11-24 01:54:37.738: E/AndroidRuntime(6971): at dalvik.system.NativeStart.main(Native Method)
11-24 01:54:37.738: E/AndroidRuntime(6971): Caused by: java.lang.RuntimeException: takePicture failed
11-24 01:54:37.738: E/AndroidRuntime(6971): at android.hardware.Camera.native_takePicture(Native Method)
11-24 01:54:37.738: E/AndroidRuntime(6971): at android.hardware.Camera.takePicture(Camera.java:1101)
11-24 01:54:37.738: E/AndroidRuntime(6971): at android.hardware.Camera.takePicture(Camera.java:1046)
11-24 01:54:37.738: E/AndroidRuntime(6971): at com.example.udptest.Main.snap(Main.java:129)
11-24 01:54:37.738: E/AndroidRuntime(6971): at com.example.udptest.Main.onCreate(Main.java:84)
11-24 01:54:37.738: E/AndroidRuntime(6971): at android.app.Activity.performCreate(Activity.java:5104)
11-24 01:54:37.738: E/AndroidRuntime(6971): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
11-24 01:54:37.738: E/AndroidRuntime(6971): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2262)
11-24 01:54:37.738: E/AndroidRuntime(6971): ... 11 more
Any ideas what might be going on here, or a better way to accomplish this task?
This is service to capture photo in background, hope it helps.:
public class CapPhoto extends Service
{
private SurfaceHolder sHolder;
private Camera mCamera;
private Parameters parameters;
@Override
public void onCreate()
{
super.onCreate();
Log.d("CAM", "start");
if (android.os.Build.VERSION.SDK_INT > 9) {
StrictMode.ThreadPolicy policy =
new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);}
Thread myThread = null;
}
@Override
public void onStart(Intent intent, int startId) {
super.onStart(intent, startId);
if (Camera.getNumberOfCameras() >= 2) {
mCamera = Camera.open(CameraInfo.CAMERA_FACING_FRONT); }
if (Camera.getNumberOfCameras() < 2) {
mCamera = Camera.open(); }
SurfaceView sv = new SurfaceView(getApplicationContext());
try {
mCamera.setPreviewDisplay(sv.getHolder());
parameters = mCamera.getParameters();
mCamera.setParameters(parameters);
mCamera.startPreview();
mCamera.takePicture(null, null, mCall);
} catch (IOException e) { e.printStackTrace(); }
sHolder = sv.getHolder();
sHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
Camera.PictureCallback mCall = new Camera.PictureCallback()
{
public void onPictureTaken(final byte[] data, Camera camera)
{
FileOutputStream outStream = null;
try{
File sd = new File(Environment.getExternalStorageDirectory(), "A");
if(!sd.exists()) {
sd.mkdirs();
Log.i("FO", "folder" + Environment.getExternalStorageDirectory());
}
Calendar cal = Calendar.getInstance();
SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd_HHmmss");
String tar = (sdf.format(cal.getTime()));
outStream = new FileOutputStream(sd+tar+".jpg");
outStream.write(data); outStream.close();
Log.i("CAM", data.length + " byte written to:"+sd+tar+".jpg");
camkapa(sHolder);
} catch (FileNotFoundException e){
Log.d("CAM", e.getMessage());
} catch (IOException e){
Log.d("CAM", e.getMessage());
}}
};
@Override
public IBinder onBind(Intent intent) {
return null;
}
public void camkapa(SurfaceHolder sHolder) {
if (null == mCamera)
return;
mCamera.stopPreview();
mCamera.release();
mCamera = null;
Log.i("CAM", " closed");
}
}
AndroidManifest.xml
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-feature android:name="android.hardware.camera" />
<service android:name=".CapPhoto" android:enabled="true">
<intent-filter>
</intent-filter>
</service>
Call this in your MainActivity to call service :
Intent service;
....
Calendar cal = Calendar.getInstance();
service = new Intent(getBaseContext(), CapPhoto.class);
cal.add(Calendar.SECOND, 15);
//TAKE PHOTO EVERY 15 SECONDS
PendingIntent pintent = PendingIntent.getService(this, 0, service, 0);
AlarmManager alarm = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
alarm.setRepeating(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(),
60*60*1000, pintent);
startService(service);
Few tips:
First of all, don't hardcode file paths. Your /sdcard might not exist at all, so your outStream will be null, and it will crash when you call any method from outStream. Instead, use Environment.getExternalStoragePublicDirectory or Environment.getExternalStorageDirectory (for devices with Android version < 2.2). See here
no photo preview - you can make your preview 1pixel x 1pixel in size, so it will be barely visible
you need to declare permissions in AndroidManifest:
"android.permission.CAMERA" and "android.permission.WRITE_EXTERNAL_STORAGE" (if you want to save pictures)
I suggest you go through the example form the docs and experiment.
This guide tell you how to build a Camera App.I hope this can help you. http://developer.android.com/guide/topics/media/camera.html#custom-camera
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