Camera and VideoOutput. Only 15 fps instead of 30 fps. Why?

MHermann

Hi,

I am developing a QML application on a Raspberry Pi 3.
I am using Camera with VideoOutput.
There I set the resoultion and the framerate.

camera.viewfinder.resolution = "640x480"
camera.viewfinder.maximumFrameRate = 30
camera.viewfinder.minimumFrameRate = 30

But I only get 15 frames/sec.
What could be the reason that I only receive 15 frames/sec?
Any ideas?

Kind regards,
MHermann

SGaist

Hi,

What camera is that ?
Can it sustain that frame rate ?

MHermann

@SGaist : This is a EPL camera.
Yes. This camera does sustain this. It runs with 640x480 and 30 fps.
But nevertheless I get only 15 fps.
Is QML slow or is the Raspian Pi 3 to slow?
Or are there other possible reasons?

SGaist

Can you check with gstreamer directly what performance you get from the camera ?

MHermann

@SGaist : Sorry for the late answer...
How can I check the performance with gstreamer?

MHermann

I just ran my application on a PC with Ubuntu 16.04.
There I get 30 fps.
Does this mean that the Rapsberry Pi itself is too slow and I will never get all 30 fps?

aha_1980

@MHermann

Does this mean that the Rapsberry Pi itself is too slow and I will never get all 30 fps?

Well, that might really be the case. Maybe this questions is better suited in a raspberry forum?

SGaist

You can't compare a multicore > 3GHz desktop machine with an embedded system like the quad core RPi3 which clocks a bit more that 1GHz.

Like I suggested, run gst-launch to see what you can get from your camera.