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screen shows only black, no camera video

June 25, 2014 - 12:16pm #1

hello

we have an application that we compile to android from Unity.

We've noticed that sometimes when starting the app and going to the scene with the AR camera, the screen shows only black without the real camera video. the tracking is still working well.

This happens mostly the first time you use the app after installing.

 

Looking in the log, i see a difference in QCAR messages:

the bad scenraio:

Setting camera clear flags to transparent black

the good scenario:

Setting camera clear flags to depth only

the good scenario:

why does this happen? what is the cause of this difference?

Thanks

Yair

 

screen shows only black, no camera video

May 7, 2018 - 1:47am #16

so many times we met, and that leads the android self camera can't open too, once open it crash.

screen shows only black, no camera video

April 4, 2018 - 2:46am #15

Having the same problem

 

Unity 2017.3.1f

iPhone 6s, iOS 11.3

screen shows only black, no camera video

January 17, 2018 - 1:11am #14

Still an issue with galaxy s8 in unity 2017.3.0f3

 

also disable 24bit no longer available 

screen shows only black, no camera video

February 25, 2017 - 1:47am #13

I was having this issue of black screen when running my app so i tried and tried but no post helped me. So here is what i did, I went to my laptop device manager and then to my camera properties and updated my camera driver and it really worked. No black screen now Yayieee!!!

screen shows only black, no camera video

September 10, 2016 - 2:47pm #12

I know it is old topic, but I'm with a HUGE PROBLEM because some devides are working well and some doesn't.

When I use ARCam with World center mode to First or Specific targes, it works well on all tested devices. However, when I change to Device Tracking, a lot of devices stop working and reports BLACK SCREEN.

I made a list with beta testers, as follows:

(OK) Samsung Galaxy S4 Mini - Android 4.4

(OK) Samsung Galaxy S2 - Android 4.0.4

(OK) Samsung Galaxy S4 - Android 5.0.1

(OK) Moto G4 Plus - Android 6.0.1

(OK) Samsung Galaxy S5  Android 6.0.1

(OK) LG K10 - Android 6.0

(OK) Moto G2 - Android 6.0

(Black screen) Samsung Galaxy Gran Prime Duos - Android 4.4.4

(Black screen) LG Volt TV - Android 5.0.1

(Black screen) Moto G1 - Android 4.4

(Black screen) Samsung Galaxy J5 - Android 5.1.1

(Black screen) Samsung Galaxy Gran Prime Duos - Android 5.0.2

(Black screen) Samsung A7 - Android 5.1.1

 

I am using Vuforia 5.5.9 and Unity 5.3.5f1 with latest Java SDK. HOW to solve this issue?

screen shows only black, no camera video

September 1, 2014 - 4:01am #11

Yes, I did try toggling this option with no affect. 

screen shows only black, no camera video

September 1, 2014 - 3:59am #10

Thanks for this update; 

sounds like this might be potentially OpenGL related (e.g. depending on specific device HW and/or OpenGL driver);

have you tried toggling ON / OFF the "Use 24-bit Depth Buffer" option in the Player Settings panel (under "Resolution and Presentation") to see if it makes any difference ?

 

screen shows only black, no camera video

September 1, 2014 - 2:29am #9

I found a solution, or at least a more exact reason as to why this issue was happening. 

I had a fullscreen UI texture (NGUI) overlay when the app started, serving as a tutorial. I found that disabling this at start up allowed the background camera rendering to kick in properly, and the tutorial screen can be toggled open later by the user to no adverse side affect. However, this same original scenario works fine on iOS, so this has to be put down as a bug on Android devices. 

I can report the same issue on a Google Nexus 7 KOT49H running 4.4.2

screen shows only black, no camera video

September 1, 2014 - 2:18am #8

Thanks SoluisDev for reporting this with the exact model and Android version. I have escalated this to our engineering team for further investigation.

screen shows only black, no camera video

August 19, 2014 - 7:38am #7

I can report this same issue on a Sony Experia Z1 (C6903) on Android 4.4.3. Black screen rendered from the AR Camera (UI from separate camera is fine) when first lanuching the scene. Go back and try again and it works as expected in terms of video rendering.

Also tested having a AR Camera set up in scene 1 (loading) with Keep alive selected. Pass through scene 2 (menu) to scene 3 (AR) and you see black background as before, only this time going back between scene 2 and 3 does not resolve the issue either. 

screen shows only black, no camera video

June 30, 2014 - 11:57am #6

Ok, thanks for confirming.

so, to summarize:

  • just running the Image Targets sample sometimes shows black camera view at the first run,
  • and this occurs on Vuforia 3.0.6 with Unity 4.5.0. 

can you also confirm that on a second run, the issue is no longer present (as tomerrei suggests in his first post) ?

Could you (both makecentz and tomerrei), provide exact Device Model number for each device and installed Android OS version, where you see this issue ?

(for example, there exist a large variety of S3 and S4 in the market, with different hardware installed);

to get the device model number, go to your Device Settings, under "About Phone" or "About Device".

Thanks.

 

screen shows only black, no camera video

June 30, 2014 - 10:52am #5

makecentz wrote:

I am having the same problem on Android for days now. Although it works well using a webcam in the editor.  On Android it loads to a black screen with no rendering of the image target. I tried this on two devices:

Samsung Galaxy S3 and S4

 

I am using:

Unity Pro 4.5.0f6

Vuforia 3.0.6

Using the Image Target Sample from SDK.

 

 

As stated before. I am using your "Image Target" sample. All steps at this point is basic. 

screen shows only black, no camera video

June 30, 2014 - 9:11am #4

Same question: can you reproduce this starting from the Vuforia Samples ?

Or else do you have some simple steps to reproduce this with a basic AR scene setup ?

 

 

screen shows only black, no camera video

June 30, 2014 - 8:56am #3

I am having the same problem on Android for days now. Although it works well using a webcam in the editor.  On Android it loads to a black screen with no rendering of the image target. I tried this on two devices:

Samsung Galaxy S3 and S4

 

I am using:

Unity Pro 4.5.0f6

Vuforia 3.0.6

Using the Image Target Sample from SDK.

 

 

screen shows only black, no camera video

June 30, 2014 - 12:28am #2

Hi,

can you reproduce this issue when you run the Vuforia Samples (for example the Image Targets sample ) ?

 

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