title: How to repaint QQuickItem quickly?
body: <p>I have a stream of images, in YUY2 format. I would like to paint these images on <code>QQuickItem</code> - so I can use it with Qt Quick 2.</p>
  
  <p>I have an issue with the performance so my question is what is the quickest way to redraw QML object written in C++? Is there some kind object dedicated to rendering videos?</p>
  
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  <p>What I have tried is creating a class that inherits <code>QQuickPaintedItem</code>. I have converted YUY2 images to RGBA8888 format, then loaded it using <code>QImage</code> and then painted it using <code>QPainter</code>. It proved not efficient if <code>QQuickPaintedItem</code> was big - for example bigger than 1000x1000. Much quicker method was to convert <code>QImage</code> to <code>QPixmap</code> and then paint using <code>QPainter</code>. It works somewhat good now but maybe there is quicker way? For example conversion of images seems too slow the process down.</p>