python3用消费者和生产者模型，实现视频流读取播放

背景：

    在做图像识别处理时候，通过opencv读入RTSP流，解码成每一帧，对每一帧做算法处理，结果会出现解码错误，然后视频读取就卡死。因此采用消费者-生产者模型，通过生产者线程进行生成（读入视频帧）存入queue队列，再通过消费者线程对视频帧进行消费处理。

代码如下：

from queue import Queue
import threading
import cv2
import time,random

class Producer(threading.Thread):
    """docstring for ClassName"""
    def __init__(self, frame_queue):
        super(Producer, self).__init__()
        self.frame_queue = frame_queue

    def run(self):
        print('in producer')
        cap = cv2.VideoCapture('rtsp://admin:[email protected]:554/MPEG-4/ch1/main/av_stream')
        print('cap is open',cap.isOpened())
        while True:
            ret,image = cap.read()
            print('get frame = ',ret)
            if (ret == True):
                self.frame_queue.put(image)
            else:
                cap = cv2.VideoCapture('rtsp://admin:[email protected]:554/MPEG-4/ch1/main/av_stream')
                print('cap is open',cap.isOpened())
                # continue

class Consumer(threading.Thread):
    """docstring for Consumer"""
    def __init__(self, frame_queue):
        super(Consumer, self).__init__()
        self.frame_queue = frame_queue

    def run(self):
        print('in consumer')
        while True:
            print('frame_queue size=',self.frame_queue.qsize())
            frame = self.frame_queue.get()
            cv2.imshow('cap video',frame)
            if cv2.waitKey(1) & 0xFF == ord('q'):
                videoWriter.release()
                cap.release()
                cv2.destroyAllWindows()
                break


if __name__ == '__main__':

    print('run program')
    #定义队列
    frame_queue = Queue()
   
    producer = Producer(frame_queue)
    producer.daemon = True
    producer.start()

    print('run  Consumer')
    consumer = Consumer(frame_queue)
    consumer.daemon = True
    consumer.start()

    producer.join()
    consumer.join()