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Camera Exposure and imageProcessing Attributes have no effect

  • Hi,
    i am trying to use the Qt functionality for changing shutter speed iso etc. But whatever I use changing the Values (in qml) has no effect on the Picture coming from the camera.

    For example I tried:


    and the effect on the camera is nothing (except the camera is restarting for the time of a blink)
    If I change the same with bridged Objective C code (referring from qml to a Objective C C++ Hybrid Class using undocumented iOS APIs) it changes the ShutterSpeed as requested.

    Is this a bug or did I miss something ?


  • Lifetime Qt Champion


    Which version of Qt and OS X are you using ?

  • I am using Qt 5.3 and OS X 10.5.8, I already tried it under Qt 5.2.1 and with Windows 7/Mac OS X 10.5.8, Qt 5.2.1/5.3 and Android 4.0/4.2 (all combinations) all with the same result.

  • Lifetime Qt Champion

    Then it's likely between a bug and a missing feature. You should go on the "bug report system": to see if it's something known. If not please open a new report providing a minimal compilable example that reproduce the behavior. In your case, you should also post your little native test app

  • Most likely the camera simply does not support that through Qt. I have a Qt camera app for three different Nokia OSs and none of them support this.

    You should check with QCameraExposure::supportedShutterSpeeds whether it is possible.

    And of course: always tell what the device is. Someone might already know what it can do.

  • Lifetime Qt Champion

    If the libs used by the backend (and the hardware of course) provides a mean to do it then I would say it's a missing feature.

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