again QGraphicsView performance

[wysota]

Use a timer to synchronize updates.

[medved6]

I said I can not. I need to draw image as soon as possible, do not wait.

[wysota]

In that case you have to live with big cpu usage. You can't eat a pie and still have the pie. You either show all images at the same moment of time or not. If not then you have to redraw the same image many times hence slowing down the application. By the way, I'm sure that if you display the camera image 5ms later than "immediately" nobody would notice. But suit yourself.

[medved6]

Ok. Thank you for the advice! I'll see if it helps, it's easy to try.
Let you know here. Thank you again!

[medved6]

Thank you.
You advice about update synchronization was very helpfull. The problem is solved.
Now I have linear increment of CPU usage with every new video. No metter how many cams do I have I do updates ( if needded ) at one shot every 25 ms.