Important: Please read the Qt Code of Conduct - https://forum.qt.io/topic/113070/qt-code-of-conduct

Qt Mac and 32 bit application



  • Hi. I have to use a video capture device on Mac. The device vendor says that, in order to use this device. I have to run my application in 32bit mode. What exactly means? This is what the vendor has said to me:

    The VideoGlide driver uses QuickTime. Because it does, the host
    application must run in 32-bit mode. If you can run your app, or any other
    app in 32-bit mode, the drover will likely work.


  • Moderators

    By default, Mac binaries are compiled in 64 bit. But you can still compile them in 32 bit mode (-arch x86 or -arch m32), and then they will work with your driver.



  • Ok, thanks.
    Can I download Qt5 x86 for Mac or have I to compile it myself?


  • Moderators

    You need to compile yourself. See "this":http://qt-project.org/wiki/Building_Qt_5_from_Git. You don't need to use git, you can download the tarball from the Downloads page. I just find the guide very useful in compiling Qt :)



  • I'm trying to compile Qt from source on Mac.
    I have tried these rows:

    ./configure -platform macx-g++42 -arch x86
    ./configure -platform macx-g++ -arch x86
    ./configure -arch i386

    but always I obtain:

    Build types: macx-g++ (x86_64, ...

    Where is the error?


  • Moderators

    See "this":https://qt-project.org/forums/viewthread/22926, maybe it will help.



  • Thanks again for your reply.
    Now I obtain the error "not supported platform". I think I have to download something for Xcode but I don't know what...


  • Moderators

    It may well be that Apple decided to trop 32 compilation support in Mavericks, I don't know (but I have not heard it said anywhere).

    You need to go to Xcode->Preferences->Downloads, then install "Command Line Tools".



  • Thank for all advices. I have installed the "Command Line Tools" as you have written but does not work. I can't produce a 32 bit application with Xcode too.
    I have written many posts in the apple developer forum without any good reply.

    I'm a beginner on develop applications for Mac but I think the Mac video capture framework is very bad.

    Is not possible to spend a very lot of time on buying video capture devices, trying many software as Vlc, QuickTime or framework as QCamera or OpenCV and discover that, the video capture devices normally work only with their own software or use 32 bit drivers.

    Do you know a usb video capture device that works on Mac and with QCamera, OpenCV and QuickTime or Vlc?


Log in to reply