👀 Views: 68 💬 Answers: 1 📅 Created: 2025-09-01

opencv python performance background-subtraction Python

I've been researching this but I've looked through the documentation and I'm still confused about This might be a silly question, but I've been struggling with this for a few days now and could really use some help... I am experiencing a significant drop in frame rate when applying the `BackgroundSubtractorMOG2` on a live webcam feed. Initially, my application runs smoothly at about 30 FPS, but once I add the background subtraction, the frame rate drops to around 5 FPS. My setup is based on OpenCV version 4.5.3, and I am using Python 3.8. Here is the code snippet where the issue occurs: ```python import cv2 import time cap = cv2.VideoCapture(0) bg_subtractor = cv2.createBackgroundSubtractorMOG2() while True: ret, frame = cap.read() if not ret: break start_time = time.time() fg_mask = bg_subtractor.apply(frame) cv2.imshow('Foreground Mask', fg_mask) print(f'Frame Rate: {1 / (time.time() - start_time):.2f} FPS') if cv2.waitKey(30) & 0xFF == ord('q'): break cap.release() cv2.destroyAllWindows() ``` I have tried adjusting the parameters of the background subtractor, such as `history`, `varThreshold`, and `detectShadows`, but nothing seems to stabilize the frame rate. My webcam resolution is set to 640x480, and I have ensured that no other processes are hogging CPU resources. Any insights into what could be causing this drastic drop in performance would be greatly appreciated, especially any optimizations or alternative methods for background subtraction that could help maintain the frame rate. My team is using Python for this REST API. Am I approaching this the right way? What are your experiences with this? This is part of a larger service I'm building. Any suggestions would be helpful.