python使用opencv截取rtsp转换成mp4

import cv2
import json
import time  # 用于替代 cv2.waitKey 的延迟

def rtsp_mp4():
    with open('demo.json', 'r', encoding='utf-8') as fp:
        opt = json.load(fp)
        
    # 获取视频流地址
    cap = cv2.VideoCapture(opt["source"])
    # 帧数
    fps = cap.get(cv2.CAP_PROP_FPS)
    # 宽高
    width, height = int(cap.get(cv2.CAP_PROP_FRAME_WIDTH)), int(cap.get(cv2.CAP_PROP_FRAME_HEIGHT))  
    size = (width, height)
    # 定义视频编码方式，保存为mp4文件
    fourcc = cv2.VideoWriter_fourcc('m', 'p', '4', 'v') 
    out = cv2.VideoWriter()
    # 视频存储对象，视频格式,帧数，视频大小
    out.open(opt["video_name"], fourcc, fps, size)
    
    try:
        while True:
            # 获取每一帧
            ref, frame = cap.read()  
            # 若没有帧返回，则重新刷新rtsp视频流
            while not ref:
                cap.release()  # 先释放之前的资源
                cap = cv2.VideoCapture(opt["source"])
                ref, frame = cap.read()  
                time.sleep(0.1)  # 避免高频重连
                continue
            
            # 翻转（如果需要）
            #frame = cv2.flip(frame, 1)
            # 保存每一帧
            out.write(frame)
            
            # 替代 GUI 的退出条件：按时间或帧数限制
            # 例如：录制 10 秒后自动停止
            if time.time() - start_time > 10:  # 自定义时间
                break
                
    except KeyboardInterrupt:
        print("用户手动终止录制")
        
    finally:
        # 释放资源
        cap.release()  
        out.release()
        print(f"视频已保存到: {opt['video_name']}")

if __name__ == "__main__":
    start_time = time.time()  # 记录开始时间
    rtsp_mp4()

demo.json内容：

{
  "source":"rtsp://admin:oetsky@2023@10.16.11.112/streaming/channels/101",
   "video_name": "demo.mp4"
}