Best way to create an OSD (on screen display with Qt)

Omer.Tal

Hey there,

I have a gstreamer pipeline which receives h264 from an RTSP source.
Then I pass the binary data to QOpenGLWidget, and then I draw using QPainter.

I've noticed that CPU is quite high, and gets even higher when FPS increases.
I was wondering if there's a way I can avoid drawing using the QPainter for each video frame, and only draw when things are actually changing on the OSD data.

Thank you
Omer

SGaist

Hi and welcome to devnet,

What kind of OSD do you have ?

Omer.Tal

Hey @SGaist,

The OSD contains mostly text, icons (QPixmaps), QPainterPaths, lines and so on...

SGaist

If these are not particularly dynamic, why not make a texture out of them and blend the image with that texture ?

Omer.Tal

@SGaist They are very much dynamic.