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Qt Multimedia and custom decoder

  • Hi,
    I've been looking for a way to display the output of a custom decoder (ffmpeg) with a VideoWidget.
    Sadly the qt5.5 VideoWidget, while saying "Video Graphics Item demonstrates how to implement a QGraphicsItem that displays video on a graphics scene using QAbstractVideoSurface." doesn't show how to use your own QAbstractVideoSurface.
    I've seen the 4.8 example and started implementing it, but I don't really see the point of using Qt Multimedia if it's just to redefine paintEvent, since the example brings nothing new. I could create the exact same behaviour without QtMultimedia.

    What I really need is mainly to be able to provide my own frames and timestamps (using QVideoFrame) without having to convert to whatever format the widget needs or having to code the paintEvent.

  • Well, after looking around it seems nobody really knows how to do this.

  • Lifetime Qt Champion

    Hi and welcome to devnet,

    You can implement a QtMultimedia backend that will use ffmpeg to read your video source or maybe the QtAV project might be of interest.

    Hope it helps