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Thread: Displaying videos with an alpha channel

  1. #1
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    Default Displaying videos with an alpha channel

    Hey

    Is there an easy way to display a video in RGBA in Qt?

    If not, do you have any ideas how to do it efficiently? Would loading every frame and displaying them in RGBA work properly?

    I want to achieve transparency to further use alpha-blending to change the background of the video as I see fit.
    Last edited by Mac91; 16th July 2013 at 11:21.

  2. #2
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    Default Re: Displaying videos with an alpha channel

    In case anyone is interested in: http://harmattan-dev.nokia.com/docs/...deowidget.html theres a solution exactly in

    Qt Code:
    1. QList<QVideoFrame::PixelFormat> VideoWidgetSurface::supportedPixelFormats(
    2. QAbstractVideoBuffer::HandleType handleType) const
    3. {
    4. if (handleType == QAbstractVideoBuffer::NoHandle) {
    5. return QList<QVideoFrame::PixelFormat>()
    6. << QVideoFrame::Format_ARGB32
    7. << QVideoFrame::Format_ARGB32_Premultiplied;
    8. } else {
    9. return QList<QVideoFrame::PixelFormat>();
    10. }
    11. }
    To copy to clipboard, switch view to plain text mode 

    it dispays the alpha channel correctly. Now for alpha-blending with the app background.
    Last edited by Mac91; 16th July 2013 at 15:29.

  3. #3
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    Default Re: Displaying videos with an alpha channel

    Turns out if you do everything correctly the QPainter items are alpha blended by default.

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