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Artificial light video preview
Posted Date: 2018-02-15 15:59     Edited Date: 2018-02-26 15:04     Writer: inactive

Dear MAXST Team,

we are using your SDK to develop a demo Unity App, using InstantTracker mode, and deploying to Android and iOS platforms.

During our test we noticed an annoying flickering of the video preview taken by the rear camera when the scene is illuminated by artificial light (neon light), like in our office. It seems there is something out of sync, something wrong with light frequency and the camera framerate.

Your demo App does have the same behaviour, while our test phone camera App (an Asus Zenfone 3) does not have any problem, video preview looks great.

Is there anything we can do to prevent this behaviour?

Thank you in advance.

Posted Date: 2018-02-19 0:33     Edited Date: 2018-02-19 0:33     Writer: inactive

Thanks for using our sdk and we're sorry for late reply because we have a traditional holidays.

Please try auto white balance lock of camera device.

We had a same issue with ODG-R7 smart glasses and solved it with auto white balance lock.

Please refer InstantTrackerSample.cs and you will find commented code like below.

//CameraDevice.GetInstance().SetAutoWhiteBalanceLock(true);   // For ODG-R7 preventing camera flickering

Could you please try to uncomment above code?

If you don't get satisfied result please try to use CameraDevice.GetIntance().SetParam() function.

Then you can adjust your camera deivce precisely.

- Maxst support team

 

Posted Date: 2018-02-19 8:26     Edited Date: 2018-02-19 8:26     Writer: inactive

Thank you for your reply.

We tried to set the auto white balance lock, but nothing changed, the flickering remains and the preview colors turned a little reddish.

We'll try now to play with SetParam(), but it seems a device-related solution that won't work for several devices, just the test one.

Thanks again.

Posted Date: 2018-02-19 23:37     Edited Date: 2018-02-19 23:37     Writer: inactive

Hi,

We are going to investigate more today and let you know the result.

- Maxst support team

Posted Date: 2018-02-23 17:22     Edited Date: 2018-02-23 17:22     Writer: inactive

Hi,

we have been trying SetParam() method a lot, using several different parameters.

Setting the antibanding parameter to 50hz solved the problem with led/tube light.

We are just wondering if it's right to set this parameter, or if it just solves the problem using our test device but it's not the right and most generic way to approch such a behaviour.

 

Posted Date: 2018-02-24 3:03     Edited Date: 2018-02-24 3:03     Writer: inactive

We're sorry for making you wait.

It's great that you could find the solution and our team is considering yours as one of the solutions.

Our sdk team has been investigating about android camera api and has got the result that some camera devices need to set their previewing fps range.

If our team can find exact solution that will be applied to next update.

Next update will be released at middle of next month.

So, please use your solution at the moment.

Thanks

- Maxst support team

 

 

Posted Date: 2018-02-26 15:04     Edited Date: 2018-02-26 15:04     Writer: inactive

Thank you very much for your support.

We will investigate on preview fps range parameter as you suggest, and wait for next SDK release.