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Camera loses auto-focus

By kennychyp on Wed, 08/01/2012 - 06:55

Hi,

I am integrating QCAR into my app. 

My app have a function that is using AVCaptureSession to show video preview.

The problem is when I follow the steps below then camera loses auto-focus.

1. new a QCAR object to recognize things (auto-focus works)

2. pause QCAR object (stopcamera, onPause) and leave the current viewcontroller

3. go to the function shows video preview

4. leave the function and release AVCaptureSession object

5. back to the viewcontroller where QCAR object is

6. resume QCAR object (onResume, startCamera) to recognize things

7. the camera loses auto-focus

 

The auto-focus function will work If I replace step 2 with release QCAR object, step 6 with new QCAR object.

But this may cause another problem - crash occasionally ( https://ar.qualcomm.at/content/crash-multiple-runs )

 

Does anyone have a solution ?

Thank you

I just checked with the developers and at present it seems this setting is not explicitly set / controlled by Vuforia - it just picks up the state it was last in.

Furthermore at present it seems as though Vuforia does not guarantee maintaining this setting between runs.

kennychyp

Mon, 08/06/2012 - 02:04

Permalink

Thank you for the answer.

However, I have two questions.

1.

Where can I submit a feature request ?

2.

I tend to solve my problem by releasing QCAR completely.

1 - submit a feature request here :  https://ar.qualcomm.at/content/wish-list

2 - I will have to check when back in the office (just over a week's time) 

N