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Thread: grab images from Phonon video

  1. #1
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    Default grab images from Phonon video

    hi,

    I'm working on an application that needs to read video files or webcams and then processes the individual video frames. I want to use phonon, because accessing the videos is so simple. But I don't see a way who I can get the imagedata of individual frames.
    My algorithems work on QImages, so I need to convert the video frames to QImages.

    I tried to use QPixmap::grabWidget(videoWidget) and then transform the QPixmap into a QImage, but I get a lot of graphic errors.

    Is there a nicer way to get video frames from Phonon? Phonon seem to be a really abstract API.

  2. #2
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    Default Re: grab images from Phonon video

    With Phonon you don't have access to single frames.
    There maybe in future support for it, but I haven't seen any commit to it yet.

    I don't think you can use Phonon for your purpose.

  3. #3
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    Default Re: grab images from Phonon video

    that is sad, although I found something interesting in http://vir.homelinux.org/blog/archiv...-+-Quasar.html

    Phonon now can give the raw video frames (as RGB, YV12 or YUY2) to an application[...]
    This sounds promising, but I could not find any other source confirming that, not even the API docs. The post is from Aug 2008, so maybe this is still beta and not included in my QT4.4.

  4. #4
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    Default Re: grab images from Phonon video

    I have read this blog post of Matthias as well.

    Let's make it short: Quasar is still in playground of KDE repository - so not even near to release.
    As KDE 4.2 is frozen it won't be released till at least 4.3.

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