Does changing v4l2 default settings improves usb camera performance?

Question

I have USB ELP camera. I'm using the v4l2 driver to capture images from that USB camera. I've found that we can change v4l2 default parameters like brightness, contrast, gamma, exposure, resolution. Can we able to increase the speed of camera access time so that it can captures images at less time by changing these parameters to optimum values?

Answer 1

Camera access time = exposure time + readout time

Changing the resolution to lower value is the best way to decrease the camera access time.

Simple example:

mono sensor with resolution 1000 x 1000

Pixclk is 50Mhz

Readout Time = (1000 x 1000) / 50Mhz = 20ms

Mono sensor with resolution 800 x 800

Pixclk is 50Mhz

Readout time = (800 x 800) / 50Mhz = 12.8 ms

Changing the exposure time to lower values will darken your image. You can avoid it by increasing the gain value, but in that case your image will be more noisely.