java.lang.NullPointerException -using opencv and android

Question

I tried to make this code work, but I have this error and I don't know how solve it:

03-23 21:51:44.705: E/AndroidRuntime(1628): java.lang.NullPointerException 03-23 21:51:44.705: E/AndroidRuntime(1628): at org.projectproto.objtrack.SampleViewBase.surfaceCreated(SampleViewBase.java:107)

According to the LogCat, you should start on line 107 in SampleBaseView. A variable on that line is null... If it is mCamera please read about open() and how you'll have trouble if you are using an emulator but haven't setup a camera. — Sam
– Sam, Commented Mar 23, 2013 at 22:45
Show us what's in line number 107 in SampleViewBase.java file. — Piotr Chojnacki
– Piotr Chojnacki, Commented Mar 23, 2013 at 22:49
that what I have in line 107 to 115: mCamera.setPreviewCallbackWithBuffer(new PreviewCallback() { public void onPreviewFrame(byte[] data, Camera camera) { synchronized (SampleViewBase.this) { System.arraycopy(data, 0, mFrame, 0, data.length); SampleViewBase.this.notify(); } camera.addCallbackBuffer(mBuffer); } }); — user2103324
– user2103324, Commented Mar 23, 2013 at 22:56

fish · Accepted Answer · 2013-03-23 22:52:27Z

1

mCamera seems to be null because Camera.open(); did not return a reference to a camera.

There are different possibilities for that. One might be a missing camera permission in your manifest file. Check it for <uses-permission android:name="android.permission.CAMERA" />

At my Nexus 7 I experienced a problem with Camera.open() as well because for some reason Camera.open(0), which is the same as Camera.open() returned null but Camera.open(1) returned a Camera object of my front camera. May be this is a general issue with devices which only have a frontcamera, but I don't know.

Anyway, this should be the place for you to look at.

Camera | Android Developers

answered Mar 23, 2013 at 22:52

fish

8181 gold badge6 silver badges15 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

java.lang.NullPointerException -using opencv and android

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related