When it comes to the format for images that will be passed to Qt Quick, the basic recommendations (as of Qt 5.8) are the following: Here the underlying image data is allocated and owned by img itself. QImage img(640, 480, QImage::Format_ARGB32_Premultiplied) The common case when generating images on-the-fly, is using QPainter and its raster paint engine to draw into a QImage: Let's now take a look at some of the common use cases and how these constructors serve the specific needs of each case. QImage(const uchar *data, int width, int height, int bytesPerLine, Format format, …) QImage(const uchar *data, int width, int height, .) QImage(uchar *data, int width, int height, int bytesPerLine, Format format, …) QImage(uchar *data, int width, int height, Format format, .) QImage(int width, int height, Format format) The interesting ones for our purposes are the following: The answer lies in some of the 9 constructors. Now, what if the image data is coming from somewhere else? For example a custom drawing made via QPainter, or an image that comes from some external engine, like a camera, scanner or computer vision framework? (although the latter would obviously be a massive overkill for image data coming from a file since that's what the Image element provides out of the box anyway). This can then be used with QPainter, can be passed to widgets, and can also be utilized in Qt Quick scenes via custom image provider implementations. Getting a QImage that contains the pixel data of an image loaded from a file is fairly self-explanatory: QImage is the most common container for image data in Qt applications. Inside QImage (with a touch of Qt Quick and OpenGL)
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