Is there a "best" QImage::Format for Raspberry Pi?

StoatPatronus

I'm using Qt 5.8 and QtQuick for a Raspberry Pi-based project. I've written a custom QQuickPaintedItem that renders a QImage to draw some data on the screen. Is there a preferred format for the QImage to get the best performance out of the Pi?

According to page 42 (Table 18) of https://web.archive.org/web/20160803202903/https://www.broadcom.com/docs/support/videocore/VideoCoreIV-AG100-R.pdf, page 42 (Table18) there are several texture formats supported by the Pi's GPU.

Since I'm not using transparency, would using QImage::Format_RGBX8888 in my Qt project be beneficial since it's supported by the GPU? I'm already generating the QImage in a separate thread to keep the GUI responsive, so I'm not really concerned about the performance, I'm just curious.

SGaist

Hi,

You should benchmark the various values that seem to fit.

petere

Hi @StoatPatronus ,

i am afraid i can't help you. Actually i am rather curious about your solution on setting the Format. I've also written my own QtQuickPaintedItem. Now i can set the renderTarget as an Image, but i don't find a way to specify the render targets format.
Please tell me how you did that.