Problem with gstreamer on Raspberry Pi 4

Python
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1

Hello, I’m working on a project for my mechatronics engineering coursewhere I need to detect circles in real time using a Raspberry Pi 4 Model B with a Raspberry Pi Rev 1.3 camera. I have configured the entire environment and ensured that the Raspberry correctly detects the camera. Furthermore, I have also reinstalled OpenCV and made the necessary updates.

The problem arises when trying to capture video with OpenCV. I’m getting several warning messages related to GStreamer and a fatal error when trying to convert the captured frame to grayscale, telling me that the frame is probably empty or not being captured correctly. Here is the code I am using and the specific errors I am getting:
Code:

import cv2
import numpy as np

# Video capture
cap = cv2.VideoCapture(0)

# Adjust image resolution (optional)
cap.set(cv2.CAP_PROP_FRAME_WIDTH, 320)
cap.set(cv2.CAP_PROP_FRAME_HEIGHT, 240)

# Defines a color range to detect red circles
lower_red = np.array([160, 50, 50])
upper_red = np.array([180, 255, 255])

while True:
     # Get the current frame of the camera
     ret, frame = cap.read()

     # Convert the frame to grayscale
     gray = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)

     # Apply Gaussian smoothing filter
     blurred = cv2.GaussianBlur(gray, (5, 5), 0)

     # Detect edges in blurred image
     edges = cv2.Canny(blurred, 50, 150)

     # Search for circles in the border image
     circles = cv2.HoughCircles(edges, cv2.HOUGH_GRADIENT, dp=1, minDist=100, param1=100, param2=30)

     # Draw the circles detected in the original frame
     if circles is not None:
         for (x, y, r) in circles[0]:
             cv2.circle(frame, (int(x), int(y)), int(r), (0, 255, 0), 2)

     # Shows the frame with the detected circles
     cv2.imshow('Circle detection', frame)

     # If the 'q' key is pressed, the window is closed
     if cv2.waitKey(1) & 0xFF == ord('q'):
         break

# Release the camera and close all the windows
cap.release()
cv2.destroyAllWindows()

Errors:

[ WARN:0@0.339] global ./modules/videoio/src/cap_gstreamer.cpp (2401) handleMessage OpenCV | GStreamer warning: Embedded video playback halted; module v4l2src0 reported: Failed to allocate required memory.
[ WARN:0@0.340] global ./modules/videoio/src/cap_gstreamer.cpp (1356) open OpenCV | GStreamer warning: unable to start pipeline
cv2.error: OpenCV(4.6.0) ./modules/imgproc/src/color.cpp:182: error: (-215:Assertion failed) !_src.empty() in function 'cvtColor'

I have verified that the camera works correctly outside of OpenCV and that updates are up-to-date. Has anyone faced a similar issue or have any suggestions on how to resolve these GStreamer errors and ensure video capture works properly?

I appreciate any help or suggestions you can offer.