Qpixmap and qimage both contain images, but there is a key difference. This is great if youre writing a oneoff program or are just experimenting with opencv, but how do you interface with your own qtbased project if. Qimage is designed and optimized for io, and for direct pixel. You can vote up the examples you like or vote down the ones you dont like. If you only want to display a qpixmap in a qlabel, you should use qlabelsetpixmap. If any error occurs when reading the image, read will return a null qimage. Qimage is designed and optimized for io, and for direct pixel access. I want to know is it possible to darken my images inside the qt using a method. Qt api has another similar class qimage, which is optimized for io and other pixel manipulations. The qpixmap class is an offscreen image representation that can be used as a paint device. If a pixmap with a depth greater than 1 is assigned to a bitmap, the bitmap will be dithered automatically. By voting up you can indicate which examples are most useful and appropriate.
Pixmap, on the other hand, is optimized for showing it on. The qimage class provides a hardwareindependent pixmap representation with direct access to. Qlabel is typically used for displaying text, but it can also display an image. Returns the alpha channel of the image as a new grayscale qimage in which each pixels red, green, and blue values are given the alpha value of the original image.
Actually i think ive found how to convert it to qimage, thank you. Only users with topic management privileges can see it. Contribute to openwebosqt development by creating an account on github. Qimage is designed and optimized for io, and for direct pixel access and manipulation, while qpixmap is designed and optimized for showing images on screen. Qbitmap is only a convenience class that inherits qpixmap, ensuring a depth of 1. The following are code examples for showing how to use pyside. Qbitmap is a qpixmap subclass ensuring a depth of 1, except for null objects which have a depth of 0. Developmenttutorialsgraphicsperformance kde techbase. There are slow functions to convert between qimage and qpixmap. Converting between cvmat and qimage or qpixmap asmaloney. You can construct the pixmap in memory by using qpixmap loadfromdata. The most common way to read images is through qimage and qpixmaps.
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