I had this problem too and only fixed it by uninstalling Unity and reinstalling version 5.3.6. Starting over in this way worked.

Unity Version 5.5.0f3 Personal 

Android Studio 2.2.3

vuforia-unity-6-2-6

MacOS Sierra Version 10.12.2

Java Platform (JDK) 8u121

NetBeans with JDK 8

App can be built for iOS, but not for Android. Black screen for Android. 

Hi,

I have the same problem here, black screen in the editor and on the device also. GUI buttons work well, so the application itself is fine, just the ARcamera doesn't get picture.

Unity version: 5.5.0f3 64 bit

Vuforia version: 6-0-114 for Unity

Unity settings:

Graphics APIs: OpenGLES2 only

Auto Graphics API: unchecked

Minimum API level: 4.0.3

Device filter: ARMv7

Stripping level: disabled

Could you please give me any advice? Thank you.

Hello,

I am not very much sure but may be this is the problem with every device having updated Marshmallow version (updated means devices which are upgradable to 6.0 but originally having lower versions) . Advanced Camera API provided in Vuforia6 has some methods to set exposure ,WhiteBalance etc but there is no proper documentation of how and where (especially with what parameters) we have to use that method in our program.

@Vuforia engineers: Does anyone maintain a list / database of devices that have reported AR Camera --> device camera access fail ("black screen") with any specifics as to reproducible use cases, and conjectures / possible fixes?

If so, could you share it please?  Or any other clues?

Our own app is using Unity 5.4.1f1, Vuforia SDK for Unity 6-0-117, building for Android min. 2.3.1.  

Here are some devices that are failing to access their cameras for this app:  (Apologies for incomplete specs)

• Samsung Galaxy J5, Android 6.0.1
• Huawei P8 Ute, Android 6.0
• HTC Desire 620, Android 6.0
• ASUS Zood, Android 5.0.1
• Samsung Galaxy S6 and S7, Android 6.0.1
• ASUS Zenphonego, Android 5.1
• BQ M5
• Samsung GT-I9515. Android 5.0.1

And some that did work:

• Samsung Galaxy S5, Android 6.0.1
• Asus Tablet, Android 6.0.1
• ASUS Zenfone 2, Android 5
• HUAWEI HONOR 5X
• Redmi Note 3, Android 5.1

I tried this, even though Im developing on MAC, it works on my old Sony Xperia phone. But when testing on my new Nexus phone the camera is still extremely dark. Though the camera were off firs, but when I were using my other phone as a flashlight and aimed it against the camera I could see faint movement. To me this seems like it could be a vuforia API problem regarding its compability with the new cameras

HI :) : i want to share my case LOOK:

I got the black screen, some post say you should delete the vuforia.jar and the vuforiaUnityPlayer.jar on Plugins/Android (because the android SDK JAR crash)..... DONT DO THAT your androids will be copiled but when you start the app it will go to black.

SOLUTION:

JAVA SDK 8 32 BITS

Download a new oracle JAVA SDK 8 for windows 86 bit (32 BITS) change the java sdk on your unity 5 file for the new one

IT WORKS FOR ME.... hope this can be usseful for some one else :)

regards:

daniel guevara

You're welcome

I've changed to OpenGL 1.x and works perfectly, thank you very much for the help.

Could you try building with OpenGL  ES 1.x settings, instead of OpenGL ES 2.0 (in landscape)?

I have found what exactly gives me problem.
In the player settings, if I choose any landscape in the orientation, I get the screen black, if I choose portrait appears the camera well.
 

I have found what exactly gives me problem.
In the player settings, if I choose any landscape in the orientation, I get the screen black, if I choose portrait appears the camera well.
 

Ok, so there is something in your Application code or scene setup that is somehow causing the issue.

It would be great if you could try to reproduce the issue by starting from one if the Vuforia samples or from a basic scene with an ARCamera  and by adding a few modifications and post a procedure to reproduce the issue based on the code/scene modifications you have made, so that we can take a look and investigate the cause of the issue..

With the teapot example, the camera run well.
 

Ok. Have you observed black screen issues on the Vuforia sample as well?

Hi

I see the issue in a mobile and a tablet.
The model mobile is the sony xperia s and the tablet model is the kindle fire hdx 8,9, both with the version of android 4.2
Its a custom application that use the AR Camera and ImageTarget prefabs.

Hi, could you add a few more details:

- do you see the issue on a specific device only? or several ?

- what is the model number of the specific device where you see black screen

- is it a custom application or one of the official Vuforia samples ?