Memory leak when there is a problematic stream

[jmspereira]

Hey everyone,

I have a setup where I connect to multiple cameras. Occasionally, one of the cameras may be defective, causing its stream to go up and down. In such cases, I attempt to reconnect to the camera using the minimal example below:

import gc
import time
import av


def connect_and_stream(stream_url: str, connection_timeout: int = 10):
    """
    Connects to a camera and streams frames. Retries connection on failure.

    Args:
        stream_url: RTSP stream URL of the camera.
        connection_timeout: Timeout for connection attempts in seconds.
    """

    capture_container = None

    while True:
        try:
            if capture_container is None:
                print("Attempting to connect to camera...")
                capture_container = av.open(
                    stream_url,
                    mode="r",
                    timeout=connection_timeout,
                    options={"rtsp_transport": "tcp"},
                )
                print("Connection established with camera!")

            stream, *_ = capture_container.streams.video
            frame = next(capture_container.decode(stream))
            _ = frame.to_ndarray(format="bgr24")
            print("Frame captured...")
        except (av.FFmpegError, StopIteration):
            print("Connection lost with camera. Retrying...")

            if capture_container:
                capture_container.close()
                capture_container = None
                
               # solves the problem
               gc.collect()

            time.sleep(10)


if __name__ == "__main__":
    connect_and_stream(stream_url="<rtsp-stream>")

However, after each reconnect the memory goes up slightly, causing a memory leak. Apparently, calling the garbage collector explicitly after setting the capture container to None solves the problem. Do you have any idea where the problem is?

Best,