Diff between QImage, QPixmap, QPicture

[wysota]

QPixmap is stored on the XServer when using X11 backend, whereas QImage is just an "array in memory" of the client program. So drawing QPixmaps on XWindow systems should be much faster than drawing QImages, as the data is already on the server, processed and ready to use.

From the programmer's point of view, treat QImage as an array of pixels and QPixmap as a "picture object" whose pixel contents are of no interest to you.