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Qt5 video player and windows 7

  • Hi,
    I was wonder if anyone else had run into this problem and if they found a way around it.
    I'm using the PyQt5 framework to create a video player that will work cross platform between windows (mostly win 7) and OSX.
    When encoded using ffmpeg and the libx264 codec, the videos look beautiful on macs and windows 10, but in windows 7 there is a brief green flash in the video before it begins playing. I have no explanation. I have all the h264 codecs installed but the issue persists. The best workaround I've found was using the mpeg4 codec with ffmpeg but the quality just isn't the same.

    I know it's a long shot because it's such a specific issue but if anyone might have any insight, it would be greatly appreciated.


  • Lifetime Qt Champion

    Being old school, i would install 100% clean win 7 in virtual machine to verify that the issue is reproducible
    on more than one win 7.
    That said, it seems your issue is not super uncommon ( old issue)

    So it might be the codec.

  • This sounds similar enough that it might be worth a try. The two pass (well it'll end up being 3-pass) process with ffmpeg and vlc isn't really a dealbreaker. I can attest that it happens on more than one Win7 box.
    I'd love to just convince IT to install windows 10 on all of our machines but that seems unlikely at the moment. Though it would likely fix the issue.

    Thanks for your input!


  • Lifetime Qt Champion


    Well im pretty sure "unlikely at the moment" is very in tune with your forum name :))

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