c++ - QImage to QPixmap is expensive -

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for application, wanted show images continuously. found took me around 30ms convert qimage qpixmap. affected frame rate, want find more effitive way show image qtgui. method can use? me?

if read documentation well, explained.

  • qimage design io handling, , direct pixel access , manipulation
  • qpixmap designed , optimized showing images on screen

if load image , show (without manipulation image), load image , cache qpixmap.

but if manipulation, nothing can do. maybe can try paint image directly qpainter of widget. don't know if faster convert image pixmap , paint widget.


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