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Multiple video display with Qt

  • Hi,

    I am kind of new to Qt and trying to develop a desktop application where I want to display multiple videos (five of them or more, no audio) on the screen. The videos will be streamed from the memory for now. I am just asking for suggestions for where to start. The options in my mind are

    • Use QGLPixelBuffer's and textures
    • Use multiple QVideoFrame's which I recently came across...

    Any other suggestions are welcome. I want to load the CPU as less as possible of course so I want to make use of the opengl buffers as much as possible. The videos are not HD or anything. Just VGA videos.


  • Hello,
    I am using the qtmultimedia example as base for my app.
    I am doing a same app where video objects are created dynamically...I'm just experiencing problem with multiple video initializations and sometimes videos swapping among my video objects.
    First thing to do (if you are using windows):

    1. download offline version of Qt without opengl (it uses ANGLE)
    2. set QGraphicsView's viewport with an instance of QGLWidget
    3. disable some optimization flags of QGraphicsView

    I've lost lots of time trying opengl version without success; opengl version use cpu decoding and ha some bug like "fast-forwording" of video. ANGLE version use directx hardware accelleration and has no bug inside

    Setting QGLWidget as viewport, speeds up your application enabling opengl

    Optimization flags, maybe can useless, but are not hurting...
    I've opened a bug on multiple instance of video object in the same app just to have official interesting and informations.

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