多线程处理时，cv2图像显示不起作用

问题描述

我正在尝试在捕获网络摄像头时将图像显示在屏幕上（我正在使用MAC）。因此，我启动了两个线程：一个用于捕获视频，另一个用于在屏幕上呈现图像：

I am trying to put images on screen while capturing webcam (I'm using MAC). Hence, I started two thread: one for capturing video, the other for presenting images on screen:

    webcam_thread = self.init_webcam_thread()
    images_thread = self.init_images_thread()

    webcam_thread.start()
    images_thread.start()

视频捕获正常运行；当我不使用线程时（这是唯一的过程），图像显示正常工作。但是，使用mutli-Threading时，所有内容均显示在白框中，而不显示图像本身。
这是图像代码：

The video capture is working correctly; The image show is working correctly while I'm not using thread (When this is the only process). However, when using mutli-Threading, all presented in a white box and not the image itself.This is the image code:

for pic_idx , pic_name in enumerate(pics):
while True:
    image = cv2.imread(pic_name, 0)
    if image is not None:
       cv2.imshow('image', image)
       k = cv2.waitKey(2000)

同样，当我不使用多线程时，我所做的只是展示图片（没有视频捕获），它运行良好。可能是什么原因？

Again, when I'm not using Multi-Thread - and all I do is presenting the pic (without the video capture) it is working perfectly. What might be the reason?

推荐答案

作为一般规则，应保留与主线程上的UI交互的所有代码。您可能要考虑使用队列，主线程从队列中拉出图像以显示图像，而其他线程则在希望显示图像时将图像推入队列。

As a general rule, you should keep any code which interacts with UI on the main thread. You might want to consider using a Queue, with the main thread pulling images from the Queue to imshow them, and other threads pushing the images into the queue when they want them shown.

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