OpenCV camera resolution

Question

I am working on a project with OpenCV. It is running on a Raspberry Pi 3 B+. When i start the camera, and do some visual processing the framerate becomes really low and there is a lot of lag. My question is: Would lowering the camera resolution solve my problem(if yes how do I do it)?

Answer 1

If you are using the full resolution and a high frame rate, it is very likely that the processor and/or memory is getting exhausted (depending on what kind of processing you are doing). So, yes, lowering the camera resolution may solve the problem.
You do not say what programming language you are using. In python you can change the resolution like this:

import cv2
cap = cv2.VideoCapture(0)
cap.set(3, 640) # Set horizontal resolution
cap.set(4, 480) # Set vertical resolution
_, img = cap.read()
cv2.imwrite("lower_res.jpeg", img)

Further reference here: https://docs.opencv.org/3.3.0/d8/dfe/classcv_1_1VideoCapture.html#a8c6d8c2d37505b5ca61ffd4bb54e9a7c